# Forum Home Renovation Retaining Walls  how to attach capping to top of besser brick wall

## chunky59

Hi all 
I have built a besser brick wall onto my garage wall to form a garden bed. 
I now want to put some capping on top of it.  I am going to use 20 mm thick black granit. 
The capping will be 170 mm wide and the besser brick wall is 140 mm wide 
Can i attach the capping to the top of the brick with it just securing by the outside of the bricks, with the holes in the middle, or should i fill the holes in the middle of the bricks up with concrete so it will give me  more surface area to adhere  the capping to? 
Also what do you use the attach the capping to the besser bricks?  Is i just sand and cement?   should i put some bondcrete in the mix?  
I have had some other capping put on by a landscaper last year and some of the capping is coming off, why would this be happening? 
chunky

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## Random Username

I'd use landscape grade liquid nails. 
Mortared capping generally comes off because the wall or capping was too dry, and all the water was sucked out of the mortar before it actually had a chance to set properly.

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## Drboost

Liquid nails, make sure the top block is nice and dry and too easy

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## barney118

recommend using a sqare piece of DPC under it.

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## johnc

You don't need to fill the blocks, the besser block will provide enough surface for the job. The traditional way of fixing granite is lead and general purpose cement. You use small 1cm or less pieces of lead sheeting, one in each corner just back from the edge either building up the lead or flattening it out to get the granite sitting square and level. You then remove the granite apply cement along the top of the besser block (creamy consistency similar to grout or slightly damper) place the granite back on the lead and give it a jiggle to seat it down onto the lead packers. Clean up the cement that oozes out with a wet sponge, and as soon as the water has dried buff with a dry cloth to get the cement residue off the polish of the granite. It will clean up easily if you do it as you go. You end up with a gap of about 3mm and you can add a bit of oxide to the cement if you wish. You can replace the lead with fibre cement sheeting to get the same effect 
I'm not a fan of liquid nails in any form for masonary and reckon you would be better off with an outdoor grade silicone or black coloured tilers caulk in preference if you wanted to go down that path.

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## REBSS

If you really want it to stay in place use an epoxy adhesive straight ontop of the blocks and place the granite on that. Epoxy is used extensively throuout the landscaping game for such things.

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## Bloss

As said above an external grade building adhesive such as Liquid Nails® Landscape | Selleys Australia or other equivalents - no need for two part epoxy.

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