Using slabs as coping stones?

[coolas4k]

Hi,

I've just built a garden retaining wall using concrete blocks which i'm currently rendering. I've been browsing some coping stones for the top of my wall but am struggling to like any at the moment. I was wondering if it would be ok to use concrete or stones slabs as an alternative? I understand they won't have the drip groove underneath but i was thinking if there's enough overhang on either side and the slabs are set completely level, the run-off water shouldn't come into contact with the wall before it drips...?

What are peoples thoughts on this please?

 

[themiddleagedun]

Yeah, go for it. There's millions of concrete blocks buried in permanently wet foundations, so a few drops running down them won't hurt.

 

[freddiemercurystwin]

The rain will still track back and down the wall to an extent but as its not a parapet on top of a building its less important.

 

[Justin Passing]

Grind your own groove?

(Sorry that sounds like a euphemism for something else... but you know what I mean?)

 

[coolas4k]

Grind your own groove?

(Sorry that sounds like a euphemism for something else... but you know what I mean?)

That's a brilliant idea!... Even if it did sound slightly dodgy 😉😂

 

[xdave]

I have much the same setup in my garden wall a couple of years ago, using stone slabs as the coping. After one season there was a bit of algae staining running down the wall in a few places so I took a small stone cutting disc and scored a small grove just in those places to break the drips. This last year the staining has not come back so it seems that is has done the job.

Or, as mentioned, you could cut them all before fitting.

If there is a chance that someone may sit/lean or walk on the wall (such as kids running along a wall adjacent to the highway) then anchor a couple of bolts into the base of the coping and set them in the mortar - preferably sunk into the top of the wall as well. A concrete or stone slab falling onto someone can cause a lot of damage and the no-win-no-fee ambulance chasers would be all over it should the worse happen.