aj mccormack and son

Other Pavings - Page 04
The Brew Cabin
other pavings


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Forum Question Replacing a gravel drive - Mark - 7 Nov 2002
Excuse the non-tech terms but I'm a layman here - a friend has a drive that slopes down to their garage with paving slabs in the tyre tracks and gravel between and to an area to the side. due to its age and falling leaves etc the gravel looks more like gritty soil/moss and they wish to revamp the lot but at low cost. I say the gravel would need removing and relaying and if another type of surface - blocks, paving etc was used then there might be drainage problems. there is only a small gully and soakaway(?) at the entrance of the garage to stop it flooding.

Any advice welcome here, thanks

forum answer Tony McCormack - 7 Nov 2002
If you replace the gravel strips with any form of solid paving (other than a permeable paver) then your chum runs the risk of flooding the garage. Have you any idea how effective is the soakaway/gully? If you put a hose to it and leave it on a steady flow, not flull blast but not a trickle, can the soakaway cope? If so, it might be worth putting in a length of linear drain across the threshold of the garage and connecting that up to the soakaway. That would allow the gravel to be replaced with block pavers, and the surface water would be intercepted by the linear drain.

However, if the soakaway is suspect or unable to cope, the only other drainage options are to create a new soakaway at some point (at least 5m from any building) or to find some way to connect the linear drain to the existing drainage system.

If all else fails, I suppose the tidiest option would be to replace the gravel with fresh stuff, and I think, given the drive's on a slope, it might be a good idea to use a cellular matrix (like the HDPE cellular grass pavers) to keep the gravel from tumbling down the slope.

Forum Question Laying tarmac in the rain - Smiler - Nov 20th 2002
My contractor is arriving tomorrow to lay a tarmac hardstanding in front of the house. Can you please tell me if it is acceptable to lay tarmac in wet weather?
forum answer Tony McCormack - Nov 20th 2002
Yes - it's usually fine, as long as there's no standing water and the rain isn't torrential.

Think about it - if laying blacktop in the rain was a serious issue, we'd never get any laid in this country!   wink

Make sure you get a written guarantee, just to be on the safe side.

Nov 20th 2002
Many thanks for your quick response to my query. I see what you mean re the British weather! Don't know why I didn't think of that. It was just that some moron had told me that only cowboy companies lay tarmac in the pouring rain! It's been a real struggle trying to find companies to give me a quote for this job so I wanted to make sure I didn't get taken for a ride.

Also, thanks for the tip about the guarantee.

Tony McCormack
Nov 20th 2002
Good luck with it, tomorrow. Let us know how you get on, and, if your contractor does a good job, give them a plug in this thread.

Don't forget to have the kettle on for them! smile

Nov 21st 2002
Well, the contractor has arrived, the privet hedge, lawn and topsoil have gone, hardcore is down and now they tell me I need a drainage gully at the bottom of the drive because it will slope from the road down to the house. It appears this was not quoted for in their original price and now they say it will add £350 to £450 to the price. The gully will be about 4ft wide and they have to locate the drain underground, which may also cause a problem as they are not sure which way the drain is running.

Their original quote was £1,690 inc. VAT and the area of the finished drive is approx. 40 sq. metres.

Can you please tell me if the price they are quoting for this drainage gully sounds fair, and shouldn't they have allowed something for this in the original price?

Tony McCormack
Nov 21st 2002
A 4ft wide gully? That's a new one - do they mean a linear drain, perhaps? And 350 quid?? Bloody hell! That's a dear do - a 1 metre section of Recyfix Linear Drain costs a tenner, but then it has to be connected, which is the great unknown, but shouldn't come to no more than 200 quid.

And yes: they should have included for the drain in their original quotation, which should have been in writing. Charging for all these sudden extras when it comes to driveways is like charging extra for tyres on a new car - it's a con.   frown

You asked for a price to install a tarmac driveway, complete. You do not expect to be charged extra for edging kerbs, drainage, access, hire of the roller, or tea-bags once you've accepted a quotation, which is why I keep banging on and on about getting written quotations that give full detail of exactly what is included in the price.

If 'extras' are required that could not have been foreseen, then that's fair enough, but surely their surveyor should have realised that the drive would backfall towards the house, and therefore, they should have allowed for that in the pricing.

Do you have anything in writing?

Nov 21st 2002
Thank you for your reply. Yes, I believe it is a linear drain. The only thing I have in writing is this chap's quote written on the back of one of his business cards. I know, I should have asked for a proper quote on headed paper and the only excuse I've got is that I'm new to this game! Even so, I do remember him saying, when he measured up the site, something about some form of drainage would be needed but he didn't commit himself as to what this would be.

Could I get away with not having this drain at all? There is a small flower bed, approx. 2ft x 10ins, up against the house wall with a concrete path between this and the bottom of the tarmac drive. To the other side of the house, on the left, there is another much larger flower bed, approx. 6ft x 2ft, where excess water could drain into. The contractor says this bed won't be much use because the drive will have to fall towards the smaller bed due to the lie of the existing concrete path on the right of the property. There is a rainwater gully with a downpipe just to the right of the small flower bed (the gully they were intending to connect to), and I wondered if it would suffice to knock one of the raised sides out (it has three raised concrete sides to it) and hope the water would drain naturally into this and the two flower beds?

I hope you can understand all this garbled info - if you can give me some idea of what to do I would be very grateful.  If only I'd found your website before I started getting quotes for this damn thing!

Tony McCormack
Nov 21st 2002
I'm not sure that the flower beds would be able to cope, and besides, it's a bit like spoiling the ship for a ha'p'orth of tar. You're paying for a decent drive: why skimp on the drainage and run the risk of waking up to find a pond outside the door one morning?

Sending water onto flower beds and gardens is all well and good if you have a lot of flower bed or garden onto which it can be sent, but if you've only a couple of small patches, you end up ruining what soil and plant life is in there, and it eventually silts up and starts to pond.

Using the existing gully sounds a possible solution, but your contractor would have to weigh-up just how feasible. However, given there is an existing gully, it should be possible to install a linear drain for a hell of a lot less than 350 quid! The presence of an existing gully means it should be a doddle to link up a metre or so of linear drain in place of the gully.

Reckon on a tenner a metre for linear drain, plus a tenner for their trouble, plus a fiver profit. That's 25 quid per metre, and then, say, 40 quid max to make a connection to the existing gully.

How about having a friendly chat with the contractor and asking how they come up with a price of 300+ quid for a ten quid length of linear drain, and could they not install something simple and functional for, say 50 quid? It's a good place to start negotiating, but try not to be pushed beyond the 100 quid limit, unless, of course, they can justify their costs and convince you that they're telling the truth.

I await news of developments with bated breath.   smile

Nov 22nd 2002
Update - the contractor has just telephoned to say he cannot do the linear drain connection for less than £300 because they have to dig up the concrete path, locate the existing drainpipe, remove that and replace it with plastic because it will be clay and it's not a good idea to connect plastic to clay. He says that he cannot do the job for any less than this because, going on past experience, until they actually start digging, they don't know what they are going to find and if the fall isn't sufficient on the existing pipe then that will have to be altered also.

I have to call him back with an answer very shortly as they want to go and get the parts so that they can get on with the job. I tried negotiating with him like you advised but he's adamant that they couldn't do it for anything less than £300. He suggested me trying to get a proper drains company to come and do the job but that would mean either holding up the laying of the tarmac or getting a firm in after the drive is laid.

He said they don't give a price for drains in their quote because every job is different and until they actually start digging down to locate drains they don't know what problems they're going to encounter.

If you can get back to me in time I would be extremely grateful but, if not, it looks as though they've got me by the short and curlies!

Contractor has just called me again to say that the total cost for the parts will be £170 - they only use top quality parts he says - plus labour for half a day's work, there are two of them working on it. He says the side gully, made by Osma?, will cost £50.

Tony McCormack
Nov 22nd 2002
Mmm. It's hard for me to say whether that's reasonable or not, as I'm not familiar with the job but, running through the points you make...

1 - connecting clayware and uPVC - they want to replace part of the existing with uPVC, but then say connecting uPVC to clay is not a good idea. It's not ideal, but there's no real problem with it. I actually prefer to use clayware, especially for shallow drainage, as it's inherently stronger than uPVC.

2 - bringing in an external contractor - yes, it would cost 300 quid plus to bring in someone else, but then, your current contractor is already on site, which should reduce the cost.

3 - not quoting for drainage - so how do they price commercial work? Do they think we would be awarded estate infrastructure contracts if we were to tell the developer that we'll tell them how much the drainage works cost once we've been awarded the job and opened the ground? Any decent contractor can 'guesstimate' how much it will cost to install a simple drainage system. This crew 'guesstimated' 300 quid the other day, before they'd opened the ground - why couldn't they have done that at the tendering stage?

4 - the 50 quid gully is about right, including the profit mark-up, but 2 men for half-a-day to install? I'm not so sure.

I think, as you say, they have you by the short'n'curlies, and you have no real room for manoeuvre, but I still believe they should have been able to inform you about the drainage before work started. It's the ability to predict and identify these issues before work commences that makes using a professional contractor advantageous. If they can't tell, in advance, that a drive sloping back towards the property will need some form of drainage, well, they shouldn't really be in the trade!

I think you'll have to accept their price, but make sure you get your written guarantee, and a full receipt for all the work they do.

Nov 23rd 2002
Many thanks Tony for your very helpful reply. I had another talk with the contractor and managed to get him to drop his price to £300 but he was insistent that they couldn't do the job for anything less. He showed me all the parts they were going to use and, I must admit, there were quite a few. &They were unable to use the £50 Osma junction drain because the existing pipe going away from the property is set too high in the ground and they wouldn't have been able to connect it to the new junction, so he deducted this from his quote and charged me £250. Well, they've reinstated the path that they had to dig up and cemented over the new pipe now. They're coming back on Monday to lay the tarmac and hang the wrought iron gates, the posts for which they concreted in yesterday along with the edging kerbs.

One other small point which cropped up yesterday - the broadband cable connection which they dug up from beneath the lawn has been buried under the haunching for the kerbs, is this standard practice? I asked them about it and was told that if we had any problems with the cable connection in the future then the service provider would simply cut off the existing cable and install a new one.

Anyway, that's the state of play at the moment - I can only hope it's plain sailing from here on in! Or is that just wishful thinking?!

Tony McCormack
Nov 23rd 2002
Good to hear you got the extra over cost for the drainage doown to 250 quid - at least that shows they're being reasonable.

Broadband cable under the haunching - well, it's not the best place for it, but it should be ok. It's sometimes run via a duct, to make replacement easier, but I wouldn't worry about it, as long as it's not damaged.

So - all set for Monday then. Fingers crossed. smile

Nov 25th 2002
Well, here we go again - the contractor arrived at 8.45, put down another layer of hardcore then two layers of tarmac. So far so good.

Unfortunately, a new problem has arisen - they came to hang the new wrought iron gates only to discover they hadn't allowed enough gap between the gate posts and the 10' wide gates (2 x 5ft) overlap each other by about 2".

They said they couldn't take out one of the posts and move it over 2" because it would ruin the drive, so they have taken one of the gates away and are getting it cut down by 2" so that it will fit.

My son, who is paying for all this, said he is not satisfied with this and wants the gate post moved. Is this possible taking into account that it has been concreted and tarmaced in place?

Nov 25th 2002
Since my last post to the forum the contractor has returned with the wrought iron gate which they have had reduced in width by about 2". They took it to a local firm of wrought iron manufacturers and it has cost them £35. They have painted over the new join for me and hung the gate.

It looks ok (from what I could see through the dusk and the fog!) and I'm all for paying them the full contract amount, £1,690 + £250 for the drainage, and calling it a day. However, my son feels they should knock something off the price for the problem they caused by not accurately measuring up the gap for the gates.

The contractor is due to come back tomorrow to bring the guarantee and receipt and collect payment - what would you advise me to do?

Tony McCormack
Nov 26th 2002
I missed your post last night - we had a family emergency and I wasn't able to check the forum after lunch yesterday.

Anyway, I think this contractor has hell of a nerve. They mis-measure the gates, and expect you to pay for their incompetence? That's really extracting the urine. Your (or your son) agreed to pay them to supply and install new gates; if they can't read a tape measure, why should you be expected to pay? On a commercial contract, they would have to bear the cost themselves, and they would not be paid a penny until they had agreed to bear the cost of the adjustments themselves.

They stung you for the drainage, which was, in my opinion, a tad unfair, and now they want you to pay for yet another 'oversight'. No way! They agreed a price for the gates, and that's all they should get.

Good luck!

Nov 26th 2002
Many thanks for your reply. Sorry to hear about your family emergency, hope everything is ok now.

Well, we didn't have to pay for the alteration to the gate but then they tried to charge VAT on the cost of the new drain. When they quoted the price for the drain, £250, they said that would be it - no mention of paying VAT on it. So, I told them no way would we pay VAT and it worked, all we've paid is the original contract price of £1,690 plus £250 for the drainage.

We were going to get the Council to do the dropped kerb for us but this firm reckon they'll do it for £50 less than the Council. After what we've just been through with them I'm not sure if we should risk using them again. However, one lesson I have learnt from this experience is to get everything in writing.

My neighbour has a query re her tarmac drive which was laid approx. 5 years ago - it is now covered with quite a lot of algae. Is it possible to remove the algae with a DIY solution or will she need it resurfacing?

Thanks again for all your help.

Tony McCormack
Nov 26th 2002
Well, you've come out of it well enough, and you have, I hope, a driveway that'll give you a decade or more of fine service. On the way, you've probably leraned more that you ever wanted to about bitmac, drainage and dealing with contractors, but, you've also learned the immeasurable value of working with a written contract-cum-agreement. That's how we do it in the trade, and that's how it should be between 'trade' and 'public'. It really is better for both sides to know what has been agreed and what hasn't.

When it comes to your dropped crossing, you must get approval from your council; that's the law, but you do not have to accept their quote. It's worth getting one or two competitive quotes on the '£xxx to do the job' variety, rather than the '£50 less than anyone else' variety. You can be extra cheeky and use the same spec as will be supplied by the council when they give you a price.

Be aware that many councils have 'approved lists' of contractors, and that, if this is the case, you are obliged to use one of these companies rather than a contractor of your own choosing. It might sound like a restriction of free choice, but it's done to ensure the cowboys are not allowed to bugger up the public footpaths quite as easily as they get away with buggering-up private driveways. Mind you, having seen the so-called repairs to the road outside our local school, I'm not so sure it's totally foolproof!   wink

As for your neighbour's driveway - the safest solution is to wash it down with a 10:1 dilution of Jeyes Fluid and give it a good scrub with a stiff brush. If the bitmac is still 'tight' and not crumbling at all, then you might be able to use a power washer, but be very careful, as the force of the jet can easily dislodge less-than-satisfactory bitmac surfacing on private driveways. As with all these clean up jobs, test a discreet area first!

Forum Question 28 days to cure concrete? - Howitzer - Aug 14th 2003
We just had our concrete driveway replaced (416 sq. ft in total) with new concrete (on Monday August 11th - a scorcher of a day). The concrete guy said that concrete needs 28 days to cure completely, and the best curing conditions is 100% humidity (which he says "that's under water"!!!). He says that I need to keep the pad wet for 28 days. I've been watering it down at least five times a day since Monday.

  1. Is this really necessary?
  2. Is this possible to keep it wet for 28 days??
  3. In the August heat wave we have right now, the temperatures are reaching 35-36 degrees Celsius (hot for Saskatchewan, Canada), it is hard to keep up - the concrete's surface dries up so fast. It seems like a big waste of precious water (yikes - our water bill!)!!!
  4. Any other comments / advice?

Regina, Saskatchewan, Canada

forum answer Tony McCormack - Aug 14th 2003
Hi again Cory,
  1. - theoretically: yes. Practically: no. Although concrete does indeed reach its design strength at (or around) 28 days, it continues to harden long after that, and actually reaches something like 90% of design strength after 5 days. Maintaining a humid curing environment is really not essential for the full 28 days.
  2. - Yes, if you set up sprayers or you live in a soggy climate like that or Ireland and Britain, but the usual practice is to use a membrane that's spray-applied to the surface to retain the water content of the concrete during the initial curing, and then peeled off after a few days.
  3. - You could cover the slab with a membrane yourself. A polythene sheet will do, or even old sacking that is dampened down every 4 hours or so. It's too late now for a sprayed membrane, and I guess, 3 days after the pour, a great deal of the initial cure is complete, especially with such high temperatures, so there's very little to be gained by using any membrane this late in the process.
  4. - Spray the concrete enought to dampen the surface and cover it with polythene for another 3 days - after that, it should be fine. You might find some minor, surface 'hairline' cracks, but these aren't worth losing sleep over, and occur in virtually all concrete. If the preparation was right before the pour, then there's not  alot to be gained by spraying, sheeting or submerging it for the next month!


Forum Question Cobble Edgings - Michelle Anderson - Jul 15th 2003
How do I construct a cobble edging between a lawn and a flower bed- can it be constructed the same way as a brick edging?
forum answer Tony McCormack - Jul 18th 2003
Do you really mean "cobbles" or do you actually mean "setts"?

The principles are more or less the same as those shown for constructing any other concrete-bedded edging, although it takes a little longer because of the variable sizes of the cobbles (or is it setts?)

Have a read of the Laying Edgings page.

Michelle Anderson
Jul 18th 2003
I did mean `Cobbles`, not setts - I've read the edgings page - but was wondering how to construct it as you would have to push the cobbles into the mortar - it would be slightly different from a brick edging, for example. Do you see what I mean? Any further help would be appreciated!
Tony McCormack
Jul 18th 2003
The size of yer cobbles makes a big difference, of course, but, the best way is to put down a concrete bed, as you would for any other concrete-bedded edging, and then top it off with 25-50mm of a decent Class II mortar, with added colour, if that's what you like. Press the cobbles into the mortar and smooth it off around the cobbles so that they are held firmly in place.

It takes a bit of practice to get the cobbles to sit evenly on the mortar bed, so that they are all at the same level and not all higgledy-piggledy, and you need to select the cobbles carefully to get a reasonably sweet line, so try not to put out too much bedding and mortar in advance of yourself until you feel more confident.

Try to make sure the cobbles are the most prominent feature of the edging, and not the mortar. Keep joints as tight as possible, and in-fill any smaller gaps with small cobbles or pebbles rather than dollops of mortar. Every metre or so, stand back and assess your work for level and alignment before moving on to the next metre. If you get any mortar on the surface of the cobbles, wipe it off asap with a damp sponge, which is also a handy tool for smoothing-off the mortar surround.

What's going either side of the cobbles?

Michelle Anderson
Jul 20th 2003
Theres going to be a flower bed to one side and a lawn on the other- and I was thinking of Scottish beach cobbles, which I suppose are the size of a spud- depending on how big your spuds are!
Tony McCormack
Jul 21st 2003
Enquiring as to the size of a gentleman's spuds is awfully forward of you, Michelle! I hardly know you!   wink

Although I've no problem with the construction, how will you get on when it comes to mowing the lawn? You'll not be able to get a mower near the cobble edge, so you'll have to use a strimmer or similar. Sounds like a lot of work.

Michelle Anderson
Jul 21st 2003
Sorry about the spuds.
Im determined to have the edging, so can I edge the side next to the lawn with timber board then - or can you think of alternative solutions to my problem which will not cause lots of extra work on the lawn side? Or am I doomed not to have my lovely `spud edge?`
Tony McCormack
Jul 22nd 2003
Worrabout using a relatively flat strip of summat on the lawn side, to act as a mowing strip? You could use, for instance, a single course of granite setts, approx 125mm wide, or a 150mm wide strip of flagstone paving. This would allow you to run the mower right over the 'mowing strip' on the lawn side but keep the Spud-U-Like edging on the flower bed side.
Michelle Anderson
Jul 22nd 2003
Dear Tone ( I know you better now)
What a good idea. Thanks so much for your time and advice and I will continue to read your pages avidly - I reckon this must be one of the best sites on the net.
Bless You xx
Forum Question Trouble sealing setts - Mick - Oct 20th 2003
Let me tell you about the bad time I have had laying granite setts in my new patio.

I followed the advice on your website and went for European fan ridged construction, apart from hitting my fingers with the rubber hammer a few times and a few blisters every thing went according to plan. Feeling a bit adventurous I decided to point them up with pitch, this was the start of my trouble. I have a friend who is a roofer so I lent his tar boiler filled it with pitch and away I went, as it heated up it was gurgling and popping and making me vary nervous. When the pitch was molten I poured it in to the can and started pointing. Having no experience I got a lot of pitch on to the setts, I thought it would just peel off, but it stuck like **** to a blanket - no amount of scraping would get it off.

After much experimentation I found a jet wash was the best tool to remove it and then it came off fairly easily. After talking to my friend the roofer he suggested lightly damping the rest of the setts before finishing off the pointing, I tried this and the pitch came off the top of the setts easily. Anyone out there pointing with pitch I would suggest pointing a small area first before going mad like I did.

Any way now the setts are finished they look beautiful. Thanks Tony and your website for giving me the inspiration to go for it.

forum answer Tony McCormack - Oct 26th 2003
It's true that the molten pitch doesn't bond as strongly to damp setts - I suspect it's probably because the pitch is cooled so quickly by the water present - but the type of sett is equally important. If you have a fine-grained igneous or metamorphic sett, such as granite, basalt or gneiss, then the pitch spillage seems to peel off quite easily, but the porous sedimentary setts, such as the gritstone and sandstone setts of northern England, the pitch seems to penetrate the pores and become stuck fast.

Wetting the setts before applying the pitch is a good idea: in fact, I may add this point to the page dealing with pitch jointing, but then great care needs to be taken because standing water and boiling pitch are a bloody dangerous combination. If you choose to dampen down your setts before sealing with pitch, give it a few minutes to soak in and for all small pools or puddles to disappear before pouring in the pitch.

Forum Question Getting quotes for gravel - Btonki - Dec 2nd 2002
We need to redo our driveway, and are keen to use gravel. Can you give me ideas on what to ask when getting quotes?

It's not that big an area - the parking area takes two cars widthways, and there is a short run to the garage, and is not 100% flat. At the moment the current drive is OLD tarmac and the parking area is grassed (mainly mud at the moment).

Is it wise to put gravel? I've been reading other threads and am starting to have second thoughts.

Thanks for all the info, my eyes are being opened. No such thing as dumping a bunch of gravel on the existing drive area, is there?

forum answer Tony McCormack - Dec 2nd 2002
If you go for the gravel option, then you need to ensure your contractor excavates the existing bitmac surfacing and gets rid of it. There may well be a suitable sub-base beneath the bitmac, and it may be possible to re-use it, once it's been re-graded and regulated (that means 'tarting up', in building trade speak).

Where you're extending over what was lawn, then that needs a new sub-base and this needs to be at least 100mm thick, preferably 150mm thick, and using a decent DTp1 material. It may also need a membrane between the sub-grade (dirt) and the sub-base (hardcore), but your contractor should advise.

The top dressing needs to be 20-30mm thick, and you're going to have to accept that it will need topping-up every year, so try to choose a local gravel that's readily available rather than summat exotic that's a pain to source in years to come, such as Spanish White Marble.

Also, bear in mind that you still need to drain the area, so make allowance for installation of gullies and/or linear drains, and a firm edging is a real benefit, as it will prevent the surfacing spreading into the adjacent garden areas. You could use any of the edging types mentioned on this site - the cheapest are timber, but, in my not so humble opinion, a brick soldier edging looks great with gravelled areas.

Simeon @ Ronacrete
Feb 19th 2003
The pavements around the houses where I live are loose gravel. My hall floor is that nice wooden flooring, very modern. Trouble is the gravel gets walked in to the house, scratches the nice wood floor, one unhappy homeowner. Even with carpet, who likes finding stones in the house, especially with bare feet!

Solution; glue the stones to the base with a fast 2 hour curing resin. My company makes it, it's called Ronadeck Fast Grip, and it's ready to use after just 2 hours.

Have a look at this PDF file or give us a call on 020 8593 7621.

Good luck.

Forum Question Two-tone PIC - Jim Watson - Jan 9th 2003
Dear GOD
thanks for allowing me to join your congregation (HELP)

Q1 - I'm laying a slub of concrete pic and would like to do two colours. Old Brick border in a Sandstone colour and the middle Tile Red slate. What is the best way to do it? Please don't tell us to get a contractor.

Q2 - What type of wood is used on a wooden bullfloat?

forum answer Tony McCormack - Jan 9th 2003
God's busy clearing a blocked drain down the lane, so I'll have to do..... smile

Q1 - Mask off one of the colour areas with a sheet of visqueen (or similar) while you spread the colour hardener over the first area, then mask t'other area and do the second colour.

Q2 - not sure, but it seems to be a fine-grained hardwood. Iroko, perhaps? The rough wooden floats used for rubbing-up work are often knocked-up on site from whatever timber is lying about, which would normally be Deal or CLS.

Ay up! There's God at the door, wanting another brew. I'd best go....! wink

Forum Question Are cell systems quieter? - Ray Hulse - Jan 16th 2003
Can anyone tell me if there is any technical information to support the premise that a driveway constructed of a cellular system such as "Golpla" infilled with gravel will provide a level of noise reduction from car traffic when compared with the same driveway simply constructed from gravel.

If so, can you direct me to the source of this information?


forum answer Tony McCormack - Jan 16th 2003
Is Coventry having a Golpla Day? That's the second Q about Golpla I've had today, and both from - makes me suspect this has been set as a coursework question! wink

Personal experience tells me it's probably true, but I don't have any empirical data to back up that belief, just my lug'oles and what they hear. Gravel driveways constructed using geo-matrices do seem quieter than loose gravel drives.

Have you tried the Golpla website? Or any of the other manufacturers? There's a list of cellular system manufacturers and links to their websites on the Grass Paving Links page.

Forum Question Tarmac Overlay - FenRam - Jan 20th 2003
I have an exisiting tarmac driveway that has small garvel rolled into it, it's been in place over 10 years and has remained in reasonable condition despite having some heavy traffic on it. I wondered if I could lay a top coat onto the exisiting tarmac and stone to enhance the appearence of the drive, if so what preperation would I need and what level of thickness would be required? Or would I have to remove the exisiting tarmac down to the sub - base and re-lay the tarmac completely? If this was the case what would be the depth required for normal vehicles (car)?


forum answer Tony McCormack - Jan 20th 2003
What you are describing is known as an "overlay" and they are dealt with on the Tarmac Basics page.

Preparation involves cleaning off any vegetation, loose material or crud, then painting on a "tack coat", and then laying 25mm or so of a 6mm wearing course macadam.

This is usually a relatively cheap job but, as always, get at least 3 quotes from reputable companies before choosing your contractor. Get a full, written specification/quotation and a guarantee.

Owt else you need to know?

Jan 14th 2003
Thanks Tony.

The Tarmac basics page seems to cover everything.


Forum Question Driveway ideas needed - N Parton - Jan 21st 2003
I'm trying to find a suitable surface for my driveway. It's currently just bare earth. I did try laying a weed-control sheet followed by loose gravel, but this caused no end of problems with local cats thinking it was giant litter tray! I've now removed the gravel and it's back to bare earth.

It's a smallish area, around 2.5m x 3m (I think!), and we intend parking a car on it. The quotes I got for laying tarmac were around £900 which is a bit out of our price range at the moment.

I've been looking into laying paving slabs, but I'm a bit concerned about them cracking with a car parked on them. Is there a cheap and cheerful solution?

I'm not expecting something that will last for years and only cost £20 as we probably will get in tarmacked in a year or two. We just need something that will last until then, and hopefully something that will be quick to implement (we're getting our first car next weekend).

Any suggestions would be gratefully received!

forum answer Tony McCormack - Jan 21st 2003
Well, you've tried the cheap option, and it didn't work. For any vehicular parking, you need a sub-base, which means digging down around 200mm and putting in 100mm of crushed stone. This is then normally paved over, with blocks or flags or bitmac or whatever you fancy. The sub-base provides the strength in a driveway.

However, once you've installed the sub-base, the rest of the paving is relatively cheap. Concrete blocks paving can be bought for around 10 quid per m² and concrete flags are a little bit cheaper. Installation is pretty easy on a small area, and, assuming your dimensions are right, you could do the lot over a weekend.

If you opt for concrete flags, then the 450x450mm wafers sold at B&Q, Wickes, Homebase, etc., are a waste of money - they're only 35mm thick and can just about manage the weight of a wheelbarrow. Even a small car will crack them into pieces, unless they're laid on concrete. If it's flags you want, then you should go for the 65mm thick units - you can get away with 50mm flags, but 65mm are a safer bet.

Easiest of all is concrete block paving. The units are small and light; they're strong enough to take the weight of anything up to a Tranny Van; they're attractive and, if you do want to surface with bitmac at some future date, they can be removed quite simply and the sub-base used again to carry the bitmac. smile

Have a look at the Excel Block Paving spreadsheet and work out for yourself how little it would cost you to DIY block pave it.

N Parton
Jan 21st 2003
Thanks for the quick reply smile

I've seen "Ground Stabilisation Sheets" in Wickes, like the ones on the GeoFabrics section of the site, is there any point in laying anything like this?

I'll look into the concrete block paving, but it seems like a lot of fuss for such a tiny driveway.

I'm hoping to at least make a start on things this weekend, so I'll report back on progress.

Thanks again for the advice!

Tony McCormack
Jan 21st 2003
Geo-membranes are designed to be laid beneath a sub-base, so you're not saving yourself any work. You still have to dig down 200mm and lay a 100mm sub-base. The geo-membranes can be useful, but I'm not sure your project warrants one.
N Parton
Jan 25th 2003
I thought I'd post a little progress report smile

Friday - Dug out the front garden so all plants were removed and the soil was a bit looser. Parents arrived, didn't have time to get a tipper van sorted, arranged to get one 9am Saturday. Demolished the front wall which was fun. Plan so far, pick up van at 9am, dig like mad and load the tipper van. Stop at 11-11:30 and take the soil to the local tip, the call in at builder's merchant for the MOT1 sub base, sharp sand and blocks.

Saturday (or er.. today)
The IDIOTS at Thrifty van rental have screwed up. No tipper van is available and no record of our booking. Apparently this has been happening a lot since they implemented a centralised call centre. GRR!
Tried to hire a big trailer with a tipper, first bloke had nothing available, HSS had one but it was expensive and would need to be collected from Hayes. That wouldn't leave enough time to get it, dig out soil, dump soil and then get back to builders yard by 12!
Builders yard (MJ Edwards) very kindly arranged to deliver all the stuff today, and we found someone who'll let us hire a small trailer for 20 quid. This has probably worked out better, because we've got all day today and tomorrow morning to dig out the soil. (if anyone near Slough needs some topsoil..).

How essential is compaction with a vibrating plate? We were hoping to get away with laying a board and sledgehammering it.

Tony McCormack
Jan 27th 2003
Wouldn't it have been easier to hire a skip to cart away the excavated material, and to allow the BM to deliver the sub-base material and everything else?

There can't be much of a cost saving in hiring a tipper van, which, unless it's a HGV, can't carry anywhere near as much as a Builder's Skip, and you pay a daily rate, whereas a skip is a one-off fee, whether you have it for a day or a week.

Anyway, how's it gone over the weekend? I've been away at a Trade Fair on Saturday and Sunday so missed all the fun! Did you get all the digging-off done?

N Parton
Jan 27th 2003
We were going to get a tipper van so we could pick up the sub base, and then go back for the sand when we were ready. The BM seemed to imply they only deliver loose aggregates, which I didn't have room for (but it turned out they delivered it in bags so that was fine)

ANYWAY! It's all done! On Saturday we dug all day, making several trips to the local refuse place (who were fine as it was domestic stuff) with the trailer. We then covered the earth with a geo-membrane (I thought it might help a bit even if not strictly necessary) and covered it with DTp1. We could have done with a bit more dtp1 as it only got around 5cm deep. frown

This morning we hired a wacker plate and compacted it, covered with a ton of sharp sand, levelled/compacted that. Then we started paving. The missus got home just as we started laying the paving. We managed to get all paving done and one bag (25kg) of jointing sand brushed over. We then gave it a couple passes with the wacker plate. We have another bag of jointing sand to add tomorrow and we're done (we may give it another pass with the wacker plate too).

I know the sub base is pretty shallow but if it lasts a year or two (with minor repairs now & again) then I'm happy! smile

I'll post some pics tomorrow (it was dark when we finished today)

Thanks a million for the help & informative site, I'd never have considered it if I hadn't seen this site.

Tony McCormack
Jan 27th 2003
5cm isn't really a sub-base, but, as you say, if it tides you over, all well and good. I'm looking forward to seeing the piccies. smile
N Parton
Jan 28th 2003
Here's a few pictures of the driveway in progress. As you can see I had a bit of help from my parents.... smile

[url=]-=>Some Pictures<=-[/url]

And the finished thing before tidying and sweeping clean:


Tony McCormack
Jan 29th 2003
Well done! It looks really good. Did you tally up how much it's cost you?
N Parton
Jan 29th 2003
Yep: in total it was £291.26 smile

£204 of that was for the Dtp1, sharp sand and all the blocks (one pack of brindle and one 'strip' of charcoal). The rest was for hiring the trailer to remove the earth, the wacker plate and bits & pieces like cement & jointing sand.


Tony McCormack
Jan 29th 2003
For 12m², that's working out at 24.27 quid per square metre, which is about half of what you'd expect to pay for a contractor to do the job, if you could get a contractor to take on such a relatively small job.

Bargain!!   smile

Forum Question Flagging my driveway - AdamUK - Jan 25th 2003
Hi Tony,
I am a new user to your excellent and informative site. ! have been reading the contents your expert advice and the experiences of the forum members has finally given me the confidence to sort out the garden area of the 'new' house I have just brought, in the Whitefield area of Manchester.

The house itself is on a main road which has no on-road parking. You have to drive the vehicle into the rear garden via a drive.

The garden size is 35ft length 22ft width. The garden is split down the middle 11ft being solid concrete and the other 11ft grassed. The concrete bit forms the parking area for 1 vehicle.

The problem is that once you have driven the vehicle you cannot reverse out under the existing layout and inturn you rely on the neighbour's garden for turning around before exiting the house.

What I would like to do is solidfy about half of grass area which when I have driven onto my existing drive would enable me reverse onto the new area and turn around.

The problem is I would like to pave the area in order to improve the appearance. However having just forked out for the house I just haven't got the money for a contracter to do it.

The existing concerete area in the garden is about 15cm higher than the grass area.

As I would be doing the job myself I would like to split the garden into three and do one area at a time. i.e dig it up.

Once I dug up the area and levelled it what do I need for the sub-base and where can I get it from? I have read on one of your replies to another post re the use of the concerete base and then laying the flags onto.

Would you recommend the same here and if so do you let the concerete dry before laying the flags on them and what should you use in between?

I am sorry if much of this is repetitive of other posts... I guess P am like the bloke who has the flu knows what medication to take, but stills ask the doctor to make sure...

I look forward to your advice.


forum answer Tony McCormack - Jan 27th 2003
The sub-base depends on the type of paving you choose. It sounds to me that you're planning to lay flags, and so, as this is a pavement that will be used by cars, you should lay the flags (which need to be at least 50mm thick, pressed concrete) onto a bed on concrete. There are two ways of doing this...

Personally, I prefer option 1, as it reduces the amount of work required, but then as a professional, I would be confident of using up a 3m³ delivery of ready-mixed concrete in 4 hours or so, whereas a diy'er might be struggling to use up 1m³ in a day.

That brings us to where the concrete is sourced. As I suggested above, I'd bring in Ready-Mix, but, if you opted to lay directly on a concrete bed/base, then it's probably easier to hire or buy a little mixer and knock out the concrete as you need it, from sand/gravel and cement stored on site.

However, if you were going for option 2, then you could bring in enough concrete as Ready-Mix to lay the sub-base in one operation, and then knock-up the laying course mortar as you needed it to lay the flags.

Which option do you think best suits your project?

Jan 27th 2003
Thx 4 the advice and the response. As I have never done anything like this before I will opt for the easier but the longer option in that I will lay the sub base first and then flag on the concrete bed.

Just want to clarify few things into my head and I apologise if I sound stupid !!

  1. - I will most likely hire a mixer and work on my own pace. For the concerete mix for the sub-base what should I use ( stone + cement ) or ( sand + cement) and what ratios?
  2. - from your experience for a 11ft x 11ft patch, how many bags of the above materials I need for the sub-base ( it is normal ground)?
  3. - once the concrete has hardened you advised that the flags should be layed on a mortar bed. What's the mix for the mortar? Am I correct in thinking its sand and cement ratio 2:1? Please advise if it is otherwise. How much mortar should I use to lay the flags on.
  4. - Would i be okay for using a rubber mallet to bed the flags?
  5. - and finally what do you recommend I use for filling any gaps between the flags.

Once again thx alot for taking the time to respond to my intial query.

Tony McCormack
Jan 27th 2003
OK: to answer your Qs one at a time....

  1. - see Concrete Mixes page as that has all the info on concretes, mixing them, ratios and recipes.
  2. - I can't work in feet, so I'll convert to metric. 11ft is, apparently 3.4m, so you've 11.6m² and it needs to be at least 100mm thick, so you need 1.2m³ of concrete for the sub-base.
  3. - Mortar bed needs to be a Class I or Class II mortar, (1:4 roughly) and you need 30-50mm to acheive a decent bed.
  4. - What else would you use??? wink
  5. - Pointing mortar - see Pointing and Jointing page

All the answers are on the site, Adam. It's just a matter of reading through the pages I quote above and coming back here if there's summat you don't inderstand.   smile

Jan 27th 2003
Thx alot for all the have been a great help...
Forum Question Sub-base for Concrete Cellular Drive - Matthew Phillips - Jan 26th 2003
I'm currently constructing a domestic driveway of approx 32 square metres and need some advice on sub-base and bedding.

I intend to lay 100mm of sub-base and then use concrete cellular blocks (100mm or 110mm depending on make) which will eventually be filled with pea-shingle or something similar. Most methods of laying blocks seem to require a layer of bedding sand after the sub-base, but I'm wondering if this sand would be pushed up the cells causing the blocks to sink when a load (e.g. my car) is pushing down. I am also relying on the cellular blocks to provide drainage (as a plain gravel drive would do).

Any comments/tips would be gratefully received,


forum answer Tony McCormack - Jan 27th 2003
I'd definitely lay the blocks on a bedding course of sand, or, if you can get it, a 5mm grit, Matthew. In fact, I can't think of any block paving system in the UK/RoI that doesn't require a laying course of sand or grit - it "cushions" the blocks and is much easier to screed to level than granular sub-base material.

There's no need to worry about the blocks 'sinking' into the sand/grit, as long as you use a decent graded material. Just make sure the edges are firm and fast, and all should be fine.   smile

Matthew Phillips
Jan 14th 2003
Thanks for that Tony, Sand it is then. Off to your 'Grit Sand Volume' calculator I go.

Is there anything this site doesn't have???

Cheers - Matt.

Tony McCormack
Feb 2nd 2003
Advertisements!  smile
Forum Question Sealing PIC - Jim Watson - Jan 31st 2003
Hi Tony
thanks for your prompt reply on my last question. Your advice was Ace.

Now we have laid our slabs and are ready for sealing with xylene. We have power-washed, removed release agent but when slab dries it looks murky with efflorescence ( I think ). I have heard of acid. Do you know type and how much to use?

By the way great site! beats the Americans.

forum answer Tony McCormack - Feb 2nd 2003
Acid won't get rid of efflorescence, Jim. It's a natural phenomenon and there's nothing you can do (at this stage) to prevent it or accelerate its disappearance. Acid (brick cleaning acid a.k.a. cement remover a.k.a. hydrochloric acid) works by reacting with the calcium-based components in concrete. It has no effect on efflorescence, other than to wash it away, but you can achieve the same result with clean water!

How old is this slab? PIC is normally sealed within 48 hours of being poured and this seems to help reduce the incidence of efflorescence (assuming the correct type of sealant is applied).

Jim Watson
Feb 3rd 2003
Hi Tony
Thanks again for your quick response.

Yes it would be great if we could seal within forty-eight hours but this is no longer sunny Greece. The slab has been down for two weeks and it has rained for two weeks. We are using xylene and thinners as a sealant. We have given it a wash down with hydrochloric acid diluted down to 7%. Today the weather is fine but we cannot do a thing.

By the way what would you use to neutralize acid? Would water do the job? Don't forget we are greener than the concrete we are working with!

Jim (Green) Watson

Tony McCormack
Feb 3rd 2003
You can neutralise the acid with plain old water - just wash it off with copious amounts, but, looking at the weather outside my window, if you were in the UK just now, Mother Nature would be giving you a hand with that!

Get the seal on as soon as the slab's been dry for 24 hours, Jim. Which sealant are you using? Is there a brand name or is it just a generic xylene-based goo?

Jim Watson
Feb 3rd 2003
Cheers Tony
We are using xylene and thinners from Replipave England

Rain again tomorrow, it's like pulling teeth. They say PIC is quicker but this is not proving the case. Building the Acropolis I'm sure took less time!

Do you drink Ouzo by any chance? We owe you a bottle of your choice.

slangie - Jim

Tony McCormack
Feb 3rd 2003
Replipave were bought out last year - how have you found the new owners?

Not so keen on the Ouzo, Jim - I like me Crested Ten or Jamesons. Tullamore Dew, too, if I can get it.   smile

Jim Watson
Feb 3rd 2003
Cheers Tony
We bought the kit October last year from their web site, which is still going.

A good man deserves a good tipple.
all the best

Tony McCormack
Feb 4th 2003
Let me know how it turns out, Jim.
Forum Question What's the best surface please? - Hacker - Feb 1t1h 2003
We have a small drive - perhaps 8m long (to what was a garage, now a room) by about 5 m wide. Enough for two cars side by side. It was 2 concrete tyre tracks which we got a travelling tradesman to tarmac over. Not the best investment I ever made. It slopes from the road down to the garage(room) with a fall of about 1m. I want to relay it with something nice and am prepared to "invest" for the future. I've noted your Brew Cabin coments on tarmac vs blocks - your preference for blocks noted.

Please advise esp with ref to the slope.

Should I go for blocks for life time especially for tyre wear cause by the slope (& already experienced)? Recommendations on individual blocks vs formed concrete? Any other thoughts for something special - there are lots of brick drives around us and your page on alternative surfaces looks fascinating but what is suitable for such a tiddly drive with a slope, pls?

Many thanks

forum answer Tony McCormack - Feb 12th 2003
I know it may come across as bias, but I honestly believe that elemental paving, such as blocks/bricks or small flags, are the best surface available for the vast majority of driveways, on grounds of costs, performance, maintenance and looks. I accept there can be problems with surface weeds, or with settlement (in some cases), but these minor irritations are relatively easy to fix, which can not be said for monolithic surfaces, such as the resin-based coverings, concrete (plain or patterned) or bitmac.

Given the gradient on your driveway, I would suggest using some form of transverse restraint at the mid point, to prevent the blocks (or flags) being 'pushed' down the slope. The actual type of block is up to you, but all of the concrete blocks from the large UK manufacturers are more than capable of coping with your driveway in terms of wear and skid resistance.

I think you're going to have to accept that there will be some tyre-marking of the surface, regardless of what surface you choose. This can, with a deal of effort, be cleaned off, but, if you go for a reversible block/brick, then you have the option to lift and invert the worst looking blocks in, say, 4 or 5 years time, and no-one will be any the wiser.

It's true that block paved driveways are becoming too commonplace, but that's because there isn't enough inventiveness shown by the designers. There is such a HUGE choice of blocks available, yet folk are still opting for the bog-standard "brindle'n'charcoal" because we are, in design terms, such a conservative nation, and folk are scared of being too adventurous.

Have a read of the 'Choosing a Block' page, which will tell you more about the wealth of choice available, and then get a few designers or contractors to take a look at your plot and see what they can come up with.

If you're looking for summat a bit different, then I'd go for one of the small element flags, say a 300x300 units, interspersed with a concrete or clay paver block. You could go for PIC, but bear in mind that you're going to have to have the sealant re-done every year, especially as you'll be driving on and off the same spots day in and day out, which always creates the 'striped' look. Or what about Resin-Bonded Aggregates?? The slope works against you, in that many of the more decorative aggregates used in the more attractive shemes, are simply not tough enough to be used on gradients of more than 1:12, so you'll find yourself being 'persuaded' to go for the Chinese Bauxite, which may or may not work with the colouration of your property.

Or you could just have it laid to tarmac. A black 'mac won't show up the tyre marks quite as much, but let's be honest, it's not going to wow anyone!

Has that given you summat to think about?   smile

Feb 12th 2003
Very many thanks!! I am delighted with the advice and will be looking at the "choosing the blocks " page right after this.

Great advice - thanks for promptness and authority. I had no idea what to do particularly as it is my wife getting the quotes whilst I am out in Ghana! I can now progress it with her from a distance!

Forum Question Update a 1970s Tarmac drive - David C - Feb 17th 2003
Cracking site, I would like some advice:

I have just moved into a 1970s Selfbuild house, it has a long tarmac drive, completely flat. It's about 30x4m with a 10x6m turning area at the end. Drive is a quality looking black tarmac, it looks like some small (less than 10mm) grey chippings were rolled in the top.

Although 30 years old and original it's in very good condition, a couple of places in the drive area it's been lifted up to 30mm by tree roots and there are a couple of very slight dents in the turning area where cars have stood. Being flat and shaded there is also a bit of moss in the corners.

She who must be obeyed wants it covered in granite chips, those light green ones about 15mm across that the merchants sell. I think what I need is some sticky bonding to glue the new chippings to the tarmac and a second (and third ?) layer on top?

Problem is the turning area can't really be built up much. I think a couple of layers of chips will be OK but it goes to the house and garage and is already 150mm from DPC - and I don't want to dig it up because of it's size and condition.

Do you think that will work? The granite chippings are no problem to find (although I have been quoted 100 pounds a ton) but where do I (can I) get the bonding stuff to stick a layer to the drive? And what is the process?

Where there is tree root damage I'll be able to put a slightly thicker layer so not too concerned about that.

Finally - I have a long 20mm masonary drill (!), before putting the chippings down should I drill some holes right through the tarmac to aid drainage or am I now just being silly!

Thanks - David C

forum answer Simeon @ Ronacrete - Feb 19th 2003
I have an answer. We manufacture Ronadeck Fast Grip, a very fast curing resin which is mixed, painted on to the surface and then blinded with coloured or natural fine aggregate. Wait 2 hours, brush or vacuum away the excess and then use the driveway again. Optionally cover with a clear seal coat. For information see our downloadable PDF File

We can provide you with names of contractors if needed.

Hope this is of some help.

Good luck
Simeon Osen
Ronacrete Ltd
Tel: 020 8593 7621

David C
Feb 19th 2003
Thanks, that sounds like it could be a solution:

Two questions:
I understand it works by bonding the chippings to the existing tarmac but is it still possible to have a loose layer of chippings on top so it looks like a conventional gravel drive. In other words do you have to use Ronadeck aggregate?

Also can you explain how/when the seal coat and primer are used?

Finally any chance of indicative costs for an area of around 720 square metres?



Tony McCormack
Feb 19th 2003
I can't fault Simeon's advice, or his company's excellent products, but I would add that it's well worth repairing the 'iffy' patches on the drive before getting the Ronadeck jollop applied.

There's a section on the site dealing with patch repairs to tarmac, and this should be done to those spots affected by tree roots or anywhere that's crumbling.

With regard to drainage; how is the existing driveway dealing with surface water? Do you have any gullies or linear drains etc? If necessary, you can install drainage before having the Ronadeck done, patch in with repair macadam, and then cover the lot with the Ronadeck, and no-one would ever know!   smile

Simeon @ Ronacrete
Feb 19th 2003

Yes, you can lay loose stones on top of the bonded stones.

No you don't have to use Ronadeck aggregates but you do have to glue aggregate into the wet resin.

Aggregate must be dry, size 0.9mm to 1.4mm. Would recommend Chinese Bauxite for strength, durability and appearance.

Primer is a component of the system and only needed when laying on to metal. ((BUT - if using the "WP" waterpoof system, which includes a flexible elastomeric membrane, unlikely to be used on a front driveway (!), it must be primed.))

Seal Coat is an optional finish which:

  1. - makes it look nicer with a slight surface sheen
  2. - seals in the stones and stops them popping out
  3. - makes it easier to clean to remove oil stains, leaf stains, etc

Material cost per m²:

resin            £6.80
aggregate   £2.00
seal coat     £3.00 per coat, 1 coat typically sufficient

Cannot quote applied prices; all subject to survey.

Life expectancy 5-10 years depending on wear, traffic, specification used, aggregate selected, maintenance and housekeeping.


David C
Feb 20th 2003
Thanks for the replies, Tony, there is no obvious drainage of the current tarmac drive, the rain just runs to the edges then seems to go through gaps in the kerb. I am planning to extend it to make the turning area a bit bigger, I've excavated just over 150mm and currently put in about 100mm of MOT type1 until I work out what to do. I think I will need to put some sort of drain in even if it is finished with gravel - I assume MOT type1 is not porus when compacted?

I will look at the resin bonded systems but over an area of 720 sqM it's not going to be cheap. Given the surface is flat what sort of problems would I get if I just put the gravel on top of Tarmac? (The angular granite type stuff about 15mm across) I'm tempted to buy a couple of bags from Wickes and experiment!

Another option might be to remove the wearing course of tarmac and put it on there, by removing the edging I can see the way the Tarmac was laid and it appears to be "text book" - ie same as on your site, although I haven't tried to seperate the layers. Might that be possible? Removing the lot to sub-base is too big a job - especially as because of trees it's difficult for heavy machinery to get access.

Reason not to retain tarmac is mainly colour, lots of trees around and need a lighter colour to reflect light into house. Gravel is best option and the stuff with the granite flecks in it looks nice as it catches the light.

Someone else mentioned the problem of walking it into the house so I'm thinking of a block paved area in front of door.

As always your advice is appreciated!

David C

Tony McCormack
Feb 20th 2003
I'll work my way through your Qs one at a time, David....

Porosity of DTp1 - it's not impermeable, but, when thoroughly compacted, it's not free-draining either. Water will find a way through it, but the speed at which it does so depends on the type of rock and how well it's consolidated. A drain is a much better solution!

Gravel on top of 'mac - No no no no no no! No! It's a bad, bad idea - it will just roll around, get swept to the sides by trafficking and act like ball-bearings on a hard floor for the pedestrians. It's a recipe for disaster.   frown

Separating the layers in tarmac - if it's been properly laid, this is impossible. If it is possible, then the 'mac wasn't properly laid.

Gravel is a bit of a PITA for getting walked into the house, especially if your have wooden floors, so an area of hard paving, be it blocks, flags, bitmac or whatever, is a good idea at the entrance - along with one of those steel grille doormat thingies! :)

Resin bond over 720 m² is going to be feasible and relatively cheap, certainly cheaper than re-paving with blocks or bitmac, and I guess there wouldn't be a great deal of difference in the cost of ripping out all the existing bitmac, paying to have it carted away and then laying a loose, un-bound gravel, or, preferably, a self-binding gravel, such as Breedon.

I'd get it priced both ways, just to see what was possible, on terms of cost. I'm sure Simeon can get one of the Resin Reps to call around, if you ask nicely.   smile

If you go for the unbound or self-binding gravel, then you've approximately 50 cubic metres of bitmac to dig up and dump, and bitmac is now classed as 'hazardous waste' because it's oil-based and it degrades over time, so it's even more expensive to dump than inert material, such as clay or rock. Any local landscaper or paving co should be able to price that option for you - and get them to include at least one drain!

FYI - we work on a very loose 'rule of thumb' that you need one gully per 200 square metres of hard surface - so you really need 4 gullies to cope with your driveway!

David C
Feb 20th 2003
Hmm lots to ponder there, as you say once you factor in the costs of removing tarmac then resin bonding looks cost effective, but I would need the bonding to just hold a layer of gravel that a second layer of gravel sits on. This is because I need to extend the drive into a new turning circle so there I assume I do the base as advised on the website with DTp1 up to the current level of the tarmac and then put 2 layer of gravel on so it matches?

Drainage is a bit of a concern - the rainwater from the house already drains to soakaways in the area the drive drains to. I know the water table is high. A while ago I dug a 1 metre deep hole for a fence post and there is still water in the bottom.

Is there any merit in drilling holes in the tarmac with a long masonary drill to allow water to drain? I suppose replacing the tarmac with something permiable might help but as there is clay underneath where does the water then go? I've been told gravel sort of holds water until the sun comes out to evaporate it but I'm not sure I believe that - but I might have to because as you explain on the soakaway section of your site, they don't work if the site is already waterlogged and there is nowhere to drain the water to!

Tony McCormack
Feb 21st 2003
I'm not sure how good a match would be possible between the section laid to bonded gravel with a loose dressing and the new section laid to sub-base with a loose surface dressing. There will be some drift of material, especially if there is any hint of a slope, and this could result in the sub-base becoming exposed in the new area.

Is it not feasible to lay a bitmac base course to the new area, then resin bond the gravels onto that and the old section in one fell swoop? Or is that just piling up the costs too far?

The grainage sounds a bit hit and miss. Drilling hole sin the bitmac is a nono. They'll fill up with crap; they'll allow the bitmac to crumble at the unsupported edges, and, if the level of the water table gets really high, they'll allow nasty, dirty silt-laden groundwater to surcharge.

We need another strategy. Is there any problem with flooding or ponding at the moment? If not, then it may be best to create a new soakaway at some handy point, and send all the surface water into that.

That theory about gravel 'holding water' is, in technical terms, utter bollocks (bollockius maximus, to give it the full title!) Gravel is free draining - water passes through, other than the miniscule amount that clings to the surface of the gravels. If there's an impermeable layer beneath a gravel, then any surface water will flood the voids between the individual grains and hang around waiting for the sun, but that's down to the impermeable layer, not to any inherent property of the gravel!

Simeon @ Ronacrete
Feb 24th 2003
I am sitting on the outide looking in so to speak. If I can assist in any way with info on the resin bonded side, please shout (or phone!).
Galley Rat
Mar 24th 2003
Great site, Tony, but you do'nt need us to tell you that!

Followed this thread with interest but confused about the effect of car tyres on resin bonded gravel (specifically my wife going from full-lock left to full lock right about 20 times in order to turn the car around). Does this not mash up the reisn bonded surface, especially if its on existing bitmac? I'm sure I read somewhere that there needs to be a proportion of the aggregate kept loose on the surface to allow for wheels to be turned.

Thanks in advance

Regards - George

Simeon @ Ronacrete
Mar 24th 2003


Your question is a good one, but you need not be concerned.

The resin we produce for bonding the aggregate (Ronadeck Fast Grip) will not suffer from the turning movement. If anything the bitmac will degrade first; it may dip and make it look as if the resin has failed.

You can of course leave loose stones on the surface but it does somehow defeat the object.

To sum up, no worries. Fast Grip will do the job. I don't know where you are geographically but we have regular contractor training days at our HQ in Dagenham, Essex and you are welcome to attend.

Some other advice:

1. keeping the car moving forwards or backwards as you / Mrs George turns the wheel will protect the driveway, and the tyres!

2. reverse in?

I hope this helps. You can telephone our Technical Support Department on 020 8593 7621 if you want more information.

Regards - and enjoy the sunshine.

Galley Rat
Apr 3rd 2003
Thanks for the response, Simeon.
I have contacted the people in your technical department, who were very helpful and friendly, and who confirmed that this can be a straightforward DIY job with proper planning, but not for one man alone. Speed and preparation appear to be key to this process.

Come the fine summer weather and a positive bank balance, and I shall be giving it a go.

Regards - George

Dave L
Apr 14th 2003
Fine spring/summer weather....? The last two weeks have been gorgeous down here

Flex that plastic!

Nice talk about the wife doing 20-point turns to park the car - I have the same trouble! wink

Simeon @ Ronacrete
Apr 15th 2003
Bless the sun for making us feel better.

Bless your credit card for enabling you to place your order (020 8593 7621) in case you needed reminding).

Bless our Technical Support Team for making hands-on training available.

Bless the little b***ards who nicked my car from the NEC last week at the External Works Show.

Dave L
Apr 15th 2003
Seems to be a pattern mate had his Subaru Impreza nicked from the very same place in January at the Autosport Show. Needless to say, he now drives a rather nice Mercedes Diesel after the insurance payout.

Think I'll take the train to the NEC next time, it might take longer (I might even miss the show, knowing the rail companies!) but at least the car is safe.

Simeon @ Ronacrete
Apr 15th 2003
I think a Reliant Robin is next for me!
Tony McCormack
Apr 15th 2003
You should have done what we did, Simeon, and paid the "exceptional parking charge" of 6 cans of Belgian Beer to the lads on the gate that enabled us to park up outside the big doors at the back of the hall.  wink

Because I had my Euro-cripple Blue Badge, we avoided the extortionate parking fees and I only had a 50m walk back to the van each night, which was a real godsend after a long day.

BTW, have you been plagued with all sorts of offers to appear in Landscape and Architect's magazines (for a nominal fee, of course!) since you got back? I didn't know there were that many trade magazines!

Simeon @ Ronacrete
Apr 16th 2003
I will next time; 6 cans of beer are worth more than the hassle and headache of losing my car - and I know where to get Belgian beer cheap now, don't I?

Offers are comig through a-plenty. Hopefully the leads we picked up at the show will more than pay for the ads.

And with the weather we are currently experiencing - 26°C today! - Ronadeck Fast Grip is going out of the factory like never before.

Nice to meet you and put a face to the name.

Have a good day.

Galley Rat
Apr 16th 2003
B*gger! Now I realise what I've been doing wrong!

I gave six cans of Fastgrip to the parking boys, and spent the weekend trying to coat my bitmac drive with aggregate spread on a Belgian beer basecoat. No wonder it wouldn't stick - even after using a Wacker plate.

Don't think I'll ever get the hang of this job. . . . .

Yours with tongue in cheek - George

Tony McCormack
Apr 16th 2003
LOL - post of the week, so far, George!   smile
Simeon @ Ronacrete
Apr 22nd 2003
And who said humour was dead!
Apr 22nd 2003
Simeon,not sure why your recommending your resin system for a driveway, when your marketing it as a flooring system? your web site case studies makes absolutely no mention of your resin surface being used in a light traffic situation! why?

I say this because i know its only designed for foot traffic and am suprised tony is letting you lead people up the garden path with such an unsuitable driveway product, i've been through all this before when looking for a new driveway for myself and have seen your product, which is great for a high grip surface on top of slippy concrete or an approach to a junction at the bottom of a steep hill, but on top of tarmac, no way jose, it is prone to delaminate, wear off under tyre use and is a bugger to clean if dirt is on it apart from being horrendously over-priced and highly toxic when applying.

Tony McCormack
Apr 23rd 2003

Thanks for your comments; you give me the perfect opportunity to publicy sell the system and its many benefits. Easy to apply, water based, SAFE, odourless, self-priming, ready in only 2 hours, very suitable for pedestrian, car, light indsutrial and heavier traffic.

I will correct the web site and thanks for identifying the gap in our marketing.

It's dissapointing that you've had a bad experience, although I doubt it was with our product.

Place an order and we'll prove the effectiveness of our system to you!

Galley Rat
Apr 24th 2003
Wow, what a response!

Ever thought of giving up manufacturing and entering politics or international diplomacy, Simeon?

Yours (relieved that Ronacrete isn't after all part of the axis of evil)   wink


Forum Question Glass blocks for a cellar - Matt - Feb 18th 2003
I've recently bought a Victorian terraced house with a coal grating (approx. 2ft x 1ft) on the pavement leading to the cellar. Anyone know where I can get glass paving bricks, either individual or pre-framed to size, to replace the grate and therefore not lose the natural light? (And I'm going to install additional airbricks to ensure adequate ventilation in the cellar, before anyone mentions it!)

Thanks - Matt

forum answer Tony McCormack - Feb 19th 2003
Luxcrete in London should be able to help - I hope you've got deep pockets!!   wink

Try their website or 'phone 0208 965 7292

Forum Question Best gravel drives for kids to play on? - Adam O'Rourke - Feb 20th 2003
I have a 35 × 4 metre existing tarmac drive. I have removed the top layer of asphalt and intent to replace it with gravel or hoggin. Ideally I would prefer to use compacted flint gravel to obtain a surface that, as well as a drive, the kids can ride a bike up and down it and kick a ball on it. Can this type of aggregate be compacted sufficiently to create the surface I require?

I had considered using hoggin but have been told that it creates a lot of dust and dirt and I would like to limit the amount of the drive that ends up in the house.

Does anyone have any advice?

forum answer Tony McCormack - Feb 20th 2003
Hoggin is a variable material and is rarely used any further north than Birmingham as we have far more sense...err, we have lots of much more suitable aggregates. I know that Hoggin is popular in the south-east, but I suspect this is mainly because there's bugger-all else to use in that aggregate-poor part of the nation.

You could choose a self-binding gravel, such as Breedon or Coxwell, which will provide a more stable surface for your kids than would loose gravel, or if you use a cell matrix system, that will help stabilise the gravel, or you could use one of the resin binders to 'fix' your chosen gravel to the existing bitmac surface.

Why are you so keen to get shut of the bitmac?

Adam O'Rourke
Feb 21st 2003
Thanks Tony for your advice.

The reason for removing the bitmac is due to the fact that I have had to dig part of the drive in order to connect a coach house at the end of the drive to the main drains. So driven by a lack of funding and a dislike of patched bitmac, I have going for one of the above solutions.


Tony McCormack
Feb 21st 2003
Assuming the sub-base beneath the bitmac is still satisfactory, have you considered having an elemental paving, such as blocks or small element flags laid? You'd get it done at a pretty good price because so much of the work (ie, the sub-base) is already in place.

It's got to be worth a phone call or two!   smile

Forum Question Permeable Tarmac - Marcus - Mar 3rd 2003
I'm building 7 houses in Boxmoor, Hemel Hemstead. I've got to use a no-dig method of construction coupled with permeable tarmac near an oak tree subject to a TPO.

What are they on about? Know any excellent contractors in Hertfordshire?

forum answer Tony McCormack - Mar 4th 2003
It's a relatively new but not uncommon method of surfacing close to trees. Any reputable blacktop contractor will be more than familiar with the materials and the laying method.

Basically, this 'system' is intended to minimise any disruption to the protected trees, especially to their rootballs, and provides a pavement surface that allows water and atmospheric gases to reach the underlying soil more or less as though there was no surfacing there.

Personally, I don't know any blacktop gangs in your part of the country. Try asking the BCO or you could ask Aggregate Industries in Hoddesdon for a quote - 01992 443480

Forum Question Bitumen layers under Gravel - Fuzileer - Mar 5th 2003
I've had three suppliers in to inspect my rather tired and grotty gravel drive, which suffers from potholing and dirty gravel, especially after heavy rain. The drive is very close to a large tree.

Two suppliers recommend a bitumen layer, the other proposes just patching the holes and compressing the sub base under the gravel prior to replacement. Does bitumen significantly extend the life?

forum answer Tony McCormack - Mar 6th 2003
So, two contractors suggest laying a bitumen binder to hold a new gravel surface dressing, but you don't say what will be used as a base. Just laying bitumen-bound gravels over the existing loose material won't necessarily be a sound construction - there needs to be suitable base layer which is usually a bitmac (tarmac).

Patching pot-holes is rarely, if ever, succesful in the long term. The existing gravel could be stripped off, the sub-grade re-graded and 'topped up' as required, and a new gravel layer placed, which is a re-vamp of what you already have. Given the presence of a large tree, this may be a better option if roots are a problem.

Mar 9th 2003
Thanks for this. I'm grateful for your expertise. There is certainly no tarmac underneath.

The "non-bitumen" supplier has proposed to strip off and take away the old gravel, and repair any problems in the sub-grade beneath and re-roll it. Then top off with new gravel.

The quote, including 31 metres of new kerb edging down one side and 31x4 metres of the above treatment, is &poun;1900. Sounds a sensible treatment at reasonable cost?

Tony McCormack
Mar 10th 2003
That price sounds fair enough. 31 metres of kerb (assuming summat simple laid on and haunched with concrete) would cost around 360-400 quid, which leaves 1500 quid for the re-gravelling. That's working out at around 12 quid per square metre, which is a fair price for the type of work under consideration, as long as it includes supply of all materials and cart away of the crap.
Forum Question Shingle Driveway - Martyn - Mar 6th 2003
Hello Tony

Well what a very informative website. I'm thinking about doing a shingle (decorative aggregate) driveway as something a bit different than block paving, I have 2 cars, my driveway is approx 9m wide by 5m deep. What I plan to do is dig out to a depth of 200mm. I was then going to lay the edging as described on this site and also lay a path down the middle of the drive from front door to footpath I was then going to lay a 150mm sub base using type1 and then lay 50mm of decorative aggregate either side of path. The questions I have are you talk about a membrane in other posts what are these and do I need one?Does the aggregate need compacting? The drive has a natural slope to the road of 6 inches is this sufficient for drainage? I live in the Essex area is there a wide selection of aggregate available?


forum answer Tony McCormack - Mar 7th 2003
Hi Martyn,

50mm depth of deco agg is a bit deep, and I think you'll find it difficult to walk on, and that the cars will 'sink' into it, leaving shallow, temporary ruts. This isn't detrimental to the stability of the driveway, but it will annoy you for a while. 35mm is a more realistic thickness for a gravel surface dressing.

The mebranes you've seen discussed are covered on their own page and while they can be beneficial, they're not always essential on a residential driveway. Have a read of that page, anyway, and then come back with any further questions.

I think you've just about enough endfall to deal with drainage. 150mm over 5m is 1 in 33, so that's fine.

For aggs in Essexcestershire, I suppose Brett Landscaping at Cliffe in Kent is the biggest supplier in the area (see Links page for contact details), but a trip to your local BM might be a worthwhile way to spend a Saturday morning, just to see what they have available.

Mar 7th 2003
Thanks for the reply Tony.

Is a 150mm sub base a bit excessive would a 100mm be sufficient? I am a bit of a stickler for doing things right also after your comments on the aggregate would a 20mm gravel/shingle be better? If whatever I use on top of sub base should I compact the finished surface or not? On your page to do with bedding the edging blocks I would be using ballast - does this mean I use about a 10 ballast to 1 cement or is this too weak a mixture?


Tony McCormack
Mar 7th 2003
100mm sub-base is the minimum. 150mm is not excessive, it's just 'erring on the side of caution'. It means more digging out, more cart away and more sub-base material to buy, but it's a stronger sub-base when you're done.

A 20mm gravel is the upper limit really. I reckon a 10-15mm is ideal for driveways, but it depends on the colour/texture etc that you choose. And yes, you should compact the gravel once it's in place. A Vib Plate is suitable, or a powered roller, whichever is easiest for you to obtain.

Finally, for the bedding concrete, if you're using an All-in Ballast (as seems to be popular in the SE) then use a 6:1 mix for bedding and haunching. You could get away with a 10:1, but I reckon that can sometimes be a bit too weak with all-in ballasts, where the proportion of fines to lumps isn't regulated.

Are you going to take piccies as you go??

Mar 7th 2003
Cheers Tony

yes I will certainly be taking pictures as I go. Another quick question, you now you can get house bricks that have been tumbled in a machine to take the edges off to make them look rustic is it possible to use these as an edging or is it better to use a block pave as the car will run over these?

Tony McCormack
Mar 8th 2003
"House" bricks (they're called 'facing bricks', really) are best left for building houses and other vertical masonry. You can get tumbled pavers that are intended to be laid in permanent contact with the damp ground and trafficked by feet and vehicles, and that's what you should use.

Horses for courses, as they say.   smile

Mar 9th 2003
Hello Tony

Well I'm all dug out to 200mm deep all over, ground underneath pretty good no roots etc. Is it ok to bed the edges with cement direct on to the soil or does it require some type1 first?

Also I wanted to construct the path before putting the type1 down for the shingle. The path was going to be flagstone with a block edging possibly on its side with recessed pointing, again I was going to do the block edging first - is this okay cemented straight on soil?

Once these had gone off I was going to lay wet cement and lay the flags. The only thing being is as I have dug out 200mm the slab will be about 115mm thick - is this okay or would you lay the path a different way bearing in mind it will get vehicle traffic? If the edges are okay being laid like this, should I point them with cement made up of sharp sand?

Just a thought is 200mm deep enough to bed the edges if I stand the blocks on there side or should I dig slightly deeper at the edges?


Tony McCormack
Mar 10th 2003
Yes, you can lay the bedding contact directly onto the sub-grade. We sometimes put down a 'blinding' of DTp1 to save on concrete, if we're going to end up using more than 100mm thickness. If you've dug down 200mm and you're using a 65mm paver, then you'd need a bed with a compacted thickness of 135mm, which is slightly excessive, so it's worth putting down 35-50mm of DTp1 first, compacting it with the vib plate, and then placing the bedding concrete.

When you say you want to put down 115mm of "wet cement", how do you come to that figure? You've excavated 200mm and you're laying 50mm thick flags, so you need a compacted thickness of 150mm of semi-dry concrete NOT "wet cement".

If you're planning to lay the brick edgings on their sides (we call it a "brick on edge" ), do the bricks in question have a presentable face if laid in that manner? If so, then you're plenty deep enough at 200mm dig, as the brick on edge is only 100mm, which leaves 100mm for bedding.

martyns path

Mar 10th 2003
Sorry Tony my mistake. I got the 115mm as I had the thickness of the type1 on my mind (150mm) and the flags we were looking at are about 35mm. Are these no good as you mention a 50mm flag?

My mistake as well - I thought you could use a wet cement to lay the flags. Is the semi dry mix a 6:1 mix if using combined ballast, as on your info pages you say use a 10:1 ratio. The brick on edge (couldn't think of the term at the time) we were probably going to use a tumbled block. After what you said about the "house brick" we are having trouble tracking down a block which looks like a tumbled house brick in brindle red any ideas?

Our house is built with red/orangy colour stocks. Sorry again about the dimension error.

Tony McCormack
Mar 11th 2003
35mm for a flag is worryingly thin, especially for a pavement that will be subject to vehicular traffic.What type of flag are they? Wet-cast patio flags, pressed patio flags, or stone flags?

The semi-dry concrete mix I'd normally use for a driveway such as this would be the C20 equivalent, which is basically a 1:6 ratio (1:2:4, roughly). You could get away with a C7.5 equivalent (1:10 or 1:3:6) with a more substantial flag, but with the wafers you're planning to use, a stronger concrete is essential.

For you brick-on-edge, I'd suggest you take a look at the Theta terracotta or Brindle from Brett Paving which may be the sort of thing you have in mind. Alternatively, some of the clay pavers, might be worth checking out.

Mar 11th 2003
We were looking at the riven type flags by Village Stone an RMC concrete product. They are wet cast replicas I think and they are 38mm thick. Are these any good or what type/supplier do you recommend? We were told these would be okay if bedded properly but like I said before I like to do things properly.

Cheers Tony

Tony McCormack
Mar 12th 2003
Yes, those are a wet-cast replica riven and really MUST be bedded on concrete if you plan to run a car over them.

To be honest, I wouldn't use them on a driveway as, in my opinion, the concrete used in manufacturing them is too soft and wears with undue haste if trafficked by vehicles on a regular basis, especially if you have one of those drives where you're driving on and off the same parts day in and day out. I'm not singling out RMC, as it's not just the 'Village Stone' flags, but most wet-cast flags suffer from the same problem. Have you seen any pressed flags that you like? Or what about some of the imported stone or even block pavers?

Mar 12th 2003
You mention pressed flags or imported stone, what supplier am I looking at for these as most brochures I have don't necessarily mention how they are made or whether they are imported or not?

We have looked at block pavng which we will edge the path in but we just thought it would set the drive off nicely with a flagged path. Some of the brochures we have say not to use there decorative paving for driveways unless otherwise stated so it would be much appreciated if you could point us in the right direction.

Another quick question - if I lay a single block around the edge of driveway and either side of the path is it possible when bedding these to leave a gap for a mortar joint and then point them in after rather than bedding them together, thought it might look better especially with the mortar joints on the flags.

Cheers Tony

Tony McCormack
Mar 12th 2003
The pressed flags are generally manufactured by the larger companies, such as RMC, Charcon, Marshalls and the like. The imported stone is supplied by these companies, as well as many of those listed on the Stone for Paving Links page.

With concrete patio flags, the manufacturers tend not to define their manufacturing process, but the vast majority of riven copies are wet cast. The pressed products are often plain or shot-textured, rather than imitation stone, which may not tie in with your plans. Have you your heart set on a riven look?

And so on to your brick edging - why do you need a mortar joint? They can be butt-jointed, if they're laid on concrete in straight lines. That's not to say you can't point them, but it's an unnecessary task. I'm not convinced that pointed flags look better with pointed brick edgings, but then, it's not my path and you should have what you want, and, if mortar joints is what you want, then it's fine to point them up after laying all the other paving.  smile

Mar 14th 2003
Hi Ya Tony

Well with lots of discussion and your advice and fors and againsts, we have decided against the flag path due to us feeling uneasy of putting something down which might not necessarily last.

We have decided to go for a tumbled block paver for the whole drive instead of path and shingle.

Now bearing in mind I have excavated to 200mm and I know I was putting shingle/gravel for the main drive which meant laying 150mm of type1, is it worth digging out another 50mm so I can still put 150mm of type1 for block paving? I know the standard depth is 100mm and obviously I've got to dig out and cart away a bit more but am I over doing it on the type1? Is there any advantages of 150mm as oppose to 100mm

We are going for the Regatta block by TopPave - just wondered what your answer was regarding the depth of type 1. Also, I know you only have to bed the edges on concrete if there is no support but the neighbours dividing wall is rather unstable and actually has no footings. Is it worth bedding this edge in concrete as if anything happens to the wall it won't effect my edge?

Once the bedding sand is laid properly and blocks are laid and you vibrate them ,do the blocks actually drop in level and if so how much?

Tony McCormack
Mar 1yth 2003
Sorry for the delay - I seem to be typing that a lot today! - I've been sussing out new products for 2003 at the Homebuilding Show at the NEC and you can see some of them in the News pages.

Anyway, on to your driveway: You should be ok with a 100mm sub-base, if you use a quality, genuine DTp1. I know Top Pave recommend a 150mm sub-base, but that is often OTT for a residential driveway unless there is iffy ground or you drive an Armoured Personnel Carrier (Shogun/LardRover/Jeep etc).

To save on extra excavation, I'd consider laying a Terram 1000 geomembrane, then a 100mm sub-base. The bedding, which should be 35-50mm and the block work can go on top of that and, in 99 drives out of 100, it will be totally problem free for years. So, your existing 200mm excavation will be sufficient, you'll be glad to know.  smile

As for the neighbour's wall - if in doubt, lay the edge blocks on concrete. It's much easier to lay them on concrete now than to face repairing it all if/when that wall falls over.

Compaction of the blocks varies from job to job, depending on the type of bedding, the depth of it, the moisture content, the type of block etc, etc, etc., but, on a typical job, the block are laid around 6-9mm high and consolidated down to flush or very, very slightly proud.

Mar 18th 2003
Thanks for the reply Tony I have just read the page on laying a screed bed which describes the reason for setting the block higher. TopPave say to use the partially compacted method but I agree with your drawbacks, is your pre compacted method really trial and error or is it not as tricky as it sounds?

Another question, DIY block paving is the topic of conversation at work at the moment as a few of us are giving it a go. A comment was raised today as to why you don't use concrete instead of type1, my answer was cost and possible drainage problems but I said I would ask you the expert for the answer.

Cheers - Martyn

P.S. The comment was raised by someone who didn't have it laid properly and the paving has sunk wi

Tony McCormack
Mar 19th 2003
I do wish the manufacturers would stick to manufacturing and leave the laying advice to those of us who have actually laid hundreds of thousands of square metres of the stuff, not just dreamt about it! I get really annoyed when I see many of the largest manufacturers suggesting spot bedding for flags and uncompacted or partially compacted screeds for block paving. frown

Although the partial compaction method is ok'd by BS7533, it's too problematic on site, as explained on the Screeding page. The pre-compaction method is not as tricky as you might imagine. If you have a screed of regular thickness, you usually find that +6mm to +9mm will give the correct level when finally consolidated, assuming you're using 50mm or 60mm blocks.

On to your Q about the sub-base - some contractors and some jobs do use a concrete sub-base, but it's more expensive than DTp1, and, on the vast majority of residential driveways, there's absolutely no call for concrete to be used as the loads imposed on the pavement are minimal. A thoroughly compacted, proper sub-base of quality material is just as reliable as concrete for light-use pavements.

There can be, as you guessed, some problem with drainage of the bedding layer when a solid base course is used in place of a flexible sub-base, and this is usually overcome by implementing some form of internal drainage, such as a composite membrane, but this brings us back to the original point that, for a standard family driveway, this is serious over-engineering.

Mar 19th 2003
Thanks for that Tony I will pass your advice on.

On the subject of sub bases if "you" were laying a 150mm bed of type1, would you do it in 2 layers of 75mm or is it best to lay it in one? Is there any advantages in doing it in 2 layers.

Cheers - Martyn

Tony McCormack
Mar 20th 2003
A 150mm thick sub-base would be laid as a single layer, normally. We only use multi-layer construction for sub-bases greater than 225mm thick, but bear in mind that the type of compaction equipment we'd use may have more 'wallop' than the little vib plates hired out to DIY'ers. However, you should be ok with a 150mm sub-base - just make sure you make a large number of passes to ensure full compaction.
Mar 14th 2003
Thanks for that Tony.

Getting back to block paving on a concrete base, one of my work colleagues is as you said going to over engineer his and lay a concrete base first. He wanted to know whether he should lay the edging first or lay the base with shuttering and leave a trench at the sides and lay and haunch the edges in after or even concrete the whole area and cement the edges on top of the base later. Also as his drive is approx 8m x 3m, he was going to divide it up with shuttering and mix and lay himself. What type of ratio mix should he use, if using combined ballast and does he need a DPM? And what about expansion joints?

Cheers Matey

Tony McCormack
Mar 20th 2003
The easiest way would be to lay the concrete sub-base on a DPM (recommended, but not essential) and screed/tamp it to level.Then, the edgings/kerbs could be laid on a mortar or damp-mix concrete on top of the concrete sub-base, assuming there is sufficient depth.

kerb base

With this type of construction, if there is expected to be greater than normal loads imposed on the retaining kerb, such as on a radius or where a vehicle might run tight against the kerb, we'd normally use a steel dowel set into the sub-base when it's placed, so that, once the haunching is put in at the back of the kerbs, it's held firmly in place. This is shown on the right hand side of the sketch.

The bedding mortar needs to be a Class II or better (see Mortars page), and no more than 25mm deep. This calls for a degree of pre-planning and accuracy when placing the sub-base. The Concrete for the sub-base should be a C20 equivalent (see Concretes page) - the DPM will help prevent a wet mix from being parched too quickly, but, if a semi-dry mix is used and wackered/rolled in place, then the DPM could be omitted. There's a calculator there to determine the quantity of 'ingredients' needed for a C20 equivalent concrete - if this mate of yours is using 'all-in ballast' then add together the sand and gravel requirements.

On an 8x3 sub-base of this type, I'd be tempted to split it into two 4x3 bays, but do so by using a plain construction joint or control joint rather than an expansion joint. An expansion joint is just a lot or faffing about on a job of this size, but, as over-engineering seems to be his prediliction, then it wouldn't do any harm if he insists.   wink

Mar 21st 2003
Sorry Tony - what's a plain construction or control joint? I have seen the page on expansion and other types of joints, but not these.


Tony McCormack
Mar 21st 2003
Are they not covered in the Concrete section? I thought they were. I'll have to check that!!

Anyway, a construction joint is simply a self-forming joint created when you finish pouring one section of concrete, allow it to start curing, and then pour against it the next day or a week later. it's just a 'break' in the pour, if you will.

A control joint is a method for persuading the concrete to crack where you want it to crack, rather than allowing it to crack just anywhere. This type of joint is usually formed by partially sawing through a concrete slab a day or so after pouring.

I'll try and knock up a couple of sketches later on.  smile

Mar 23rd 2003
If he divides it up into two 4x3, obviously the joint will be down the centre but also on one of the slabs one edge will be up against an existing garage slab, another edge will be against the footpath, and the third edge up against a wall. Should there be any expansion joints at either end where it meets the garage or footpath or is the one down the centre sufficient?

Also will he need to put a mesh for reinforcement in the slabs as well.


Tony McCormack
Mar 25th 2003
In answer to the problem, I've now added a section on Construction Joints to the Concrete Joints page, which may be helpful. However, Given the scale of this pour, I really don't think expansion joints are essential, but, if you're really keen, one central expansion joint in place of the proposed central construction/control joint will be plenty.

Reinforcing mesh is not needed for this type of project. It's much simpler and considerably cheaper to use fibre reinforcement, which the Ready Mix company can add to the concrete on demand, or you can buy at your local BM for around a fiver. No awkward cutting of mesh, no nasty cuts to the hands when placing the mesh, no getting the wellies trapped in the mesh, no worrying about depth of cover....much, much simpler for a basic slab.  smile

Mar 30th 2003
Hello Tony

thanks for the reply and the description of a construction joint.

Anyway back to the drive - the wife wants a curvy flower border just in front of the wall, I have read your page about edges etc and you mention the max gap for sand between edgings as being 10-13mm. We roughly planned the shape out and the gap was about 5mm plus. If I raise the edges up so they are about 100mm above the level of the drive, I take it that you can't sand these gaps as the sand will fall out. If I use mortar, whats the min and max gap you have done with mortar that you think looks okay? Or is it best with a gap of 5mm plus to leave it without any filler at all?

Cheers - Martyn

Tony McCormack
Mar 31st 2003
Hi Martyn,

with the upstand and the tightness of the joints you've described, I would either leave them dry, ie, no sand, no mortar, or I would separate the units a little more and make them 12mm wide mortar joints. If forced to choose, I'd go for the mortar joints as I always think they look neater and suggest a more professional finish, but the choice is yours.  smile

Minimum joint width, realistically, for a mortar finish is 6mm (what used to be a quarter-inch in old money) and the maximum, to my way of thinking, is 20mm, but 12mm is ideal, with 10-15mm being 'acceptable'.


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