Introduction:
The market for resin-based jointing compounds is more crowded than ever. 20-cough years ago when this website first started covering these products, that then niche market was massively spurred on by the arrival in Britain of a market-leading product from Germany, which effectively doubled the number of compounds on the market at that time. That brand went from strength to strength and established itself as one of the leading names in the sector.
Now, from that same part of the world, we have A-Joint, which promises everything we expect from the popular German brands but with enhanced technical support, constant product development, and a more user-friendly approach.
The team behind A-Joint, a group of highly experienced British, Irish and European distributors working with a long-established and well-respected German manufacturer specialising in resin products. They wanted to be able to provide a wholly new product fit for the 21st century but with a familiar feel. This starts by establishing key performance criteria, and then ensuring the range of mortars produced are simple and comfortable to work with, but familiar in the method of installation.
Some of the recent entrants onto the resin mortar scene have, bafflingly, decided to “re-invent the wheel” by developing different and, it has to be said, overly complicated installation methods. A-Joint wanted to stick with what installers know best: simple brush-in products for low traffic projects (Cat 1 pavements), and a selection of easily-cleaned slurry mortars for driveways (Cat's 2 & 3), and public realm pavements (Cat's 4 and above) that carry vehicular traffic. No new methods to learn; no tricky techniques to follow; no fancy new tools required – it’s all resin mortars as we know and love them, but with enhanced tech support and added oomph!
The Range:
Initially, there are four key products, two 1-component compounds (1K or 1-part), and two high performance 2-component mortars (2K or 2-part) for more demanding installations:
1-Component Brush-In jointing compounds
A-Joint Ready
- Pedestrians, cycles and small cars (Cats 1 & 2)
- 15kg and 25kg buckets
- Resists scour by pressure washers
- Highly water permeable; frost resistant
- Air-cured in 24 hrs for foot traffic and 6 days for small cars
- For typical joints – 5-20mm
- Ideal for stone and concrete pavings
- Minimum 30mm depth
A-Joint Ready Flex
- Pedestrians and cycles (Cat 1 pavements)
- 15kg buckets
- Resists scour by pressure washers
- Flexible: can be used with unbound pavings
- Air-cured; water permeable; frost resistant
- For narrow joints – 3-5mm
- Ideal for porcelain
- Minimum 20mm depth
2-Component Slurry Jointing Mortars
A-Joint Pro
- Up to 12T loads (cats 1-4)
- 25kg buckets and 27.5kg bags
- Frost and de-icing salt resistant
- Water permeable
- Self-compacting
- Joints from 3mm width
- Minimum 25mm depth
A-Joint Traffic
- Up to 40T loads (Up to Cat 6/7)
- 27.5kg bags
- Rapid cure: 6hr for foot traffic; vehicular use after 24hrs
- Weed, scour, street sweeper/vacuum, and frost resistant
- Self-compacting
- Slightly permeable
- Joints from 3mm wide
- Minimum 30mm depth
Colours:
All mortars are available in three consistent and stable colours: Neutral (beige sand); Stone Grey (beige to mid-grey); and Basalt (dark grey to almost black).
Like most German-manufactured resin mortars, access to massive, reliable and cost-effective continental aggregates means that the colours are consistent from month-to-month, and year-to-year. The Basalt mortar installed in 2022 will be the very same colour as that installed in 2025 or in 2030, and because the colours are natural, not dyes, and they retain that hue throughout their life, regardless of how often they are scrubbed, hosed, or power-washed. They cannot fade: that’s their natural colour!
Application:
1-component products:
A-Joint Ready and A-Joint Ready Flex
- For best results, the paving to be jointed must be thoroughly pre-wetted
- Open vacuum-sealed bag and empty pre-coated mortar onto pavement surface
- Working Life of around 30 minutes from opening of vacuum pack
- Spread using a squeegee or fine broom, pushing the ready-mixed mortar into the open joints with the squeegee blade or a pointing iron
- Wash-in with fine water spray if necessary – very useful for narrow joints
- Remove any excess from the surface immediately, as soon as joints are filled by sweeping across joints in a diagonal direction using a fine broom
- Ensure all surplus mortar is removed. The tailings should not be re-used.
- When rain is expected in first 24 hours, cover with a tarpaulin or similar
2-component products:
A-Joint Pro and A-Joint Traffic
As two-part products, Pro and Traffic will need to be mixed before use.
A-Joint Pro is available in both buckets and bags, while A-Joint Traffic is supplied in bagged format only
This brief guidance is for the bucket-packed version of both A-Joint Pro. For A-Joint Traffic and the bag-packed version of A-Joint Pro, consult the individual Technical Data Sheets
- The paving to be jointed must be wetted before applying the mortar. This is best done before mixing the mortar with an additional wetting immediately prior to application
- Each bucket of A-Joint Pro contains the pre-coated fine aggregate with a separate bottle of activator, all of which will need to be completely added to the aggregate
- Rinse out the activator bottle with 0.25 litres of clean, cold water and add this to the bucket
- Use a professional grade paddle stirrer to work the activator through the aggregate for at least 6 minutes when a creamy, flowing mortar should have developed
- Working Life is around 20-30 minutes at 20°C ambient temperature
- Re-wet the surface to be jointed, empty the mixed A-Joint Pro onto it, and spread it over the surface using a rubber-bladed squeegee crossing the joints diagonally, and pushing the mortar into the open joints
- Ensure joints are fully filled
- After around 10-20 minutes, when the mortar no longer produces white-ish streaks when brushed, use a medium bristle broom sweeping diagonally to remove any excess mortar from the surface, then follow with a fine-bristle coconut fibre broom to remove the final grains of mortar
- Ensure all surplus mortar is removed. Any tailings should not be re-used
- When rain is expected in first 24 hours, cover with a tarpaulin or similar
Residue:
As with many other resin mortars, A-Joint pavement mortars may leave a light residue that will cure to a film. With some paving materials, this film may enhance the colouring, imparting a damp or wet look, but be advised this is a purely temporary phenomenon. That film *will* weather and abrade and, in most situations, will have fully disappeared in a matter of weeks, returning the surface to original, intended, natural appearance.
For those that prefer to colour-enhanced or damp look, there are specialist products available that provide a much longer-lasting or permanent enhancement.
Gallery:
Case Study 1:
Here's a simple job from Germany, where restraining edge courses and a central restraining course have been laid in advance and need to be jointed before the unbound block paving is laid between the courses.
The blocks have been laid on a concrete bed and the sides of the open joints have been taped-up to keep the fluid A-Joint Pro jointing mortar in place while it cures. After a day or so, the tape can be peeled off and the paving works can continue.
Mix and pre-wet the restraining course blocks
Pour A-Joint onto wetted blocks
Use squeegee to work mortar into joints
As a team, one operative applies the A-Joint, one squeegees it into the joints, and a third cleans off
Squeegees work best on smooth pavings
Continue applying the A-Joint Pro
After cleaning off, the A-Joint mortar is allowed to cure
It needs around 24 hrs to cure
The process is repeated for other restraining courses
Job complete in next to no time and with no staining
Video:
Some readers may recall a decorative patio feature in the form of a Celtic Knot installed back in 2008-9 as a demonstration of installation techniques. That little patio is still with us but recent changes to the garden area involved burying an electricty cable and an irrigation supply pipe which resulted in around a third of the paving being lifted and re-laid.
Consequently, the patio required re-jointing, and at more-or-less the same time, A-Joint got in touch looking for suitable small patio or back garden case studies for their new range of resin-based jointing mortars.
Here's how it all went....
Further information:
A-Joint
C/O Cowley Stone,
Thorpe Salvin,
Worksop
S80 3LA
Tel: 01909 772 302
