Why Should Paving Slabs Be Laid On A Wet Mix?

[EViS]

There seems to be differing opinions in regards to whether paving should be laid on a wet mix of mortar (4:2:1 sharp:building:cement) or semi-dry mix.

What are the pros and cons of laying on a wet mix vs semi-dry mix?

 

[imamartian]

I'm a DiYer, but i don't think it really matters. You can get good results with either method. So it's personal preference.
I prefer a complete bed of wet mix.... i find it easier to get the slabs about right, and they tamp down more nicely.

Dotting corners, i reckon is bad... and lazy.

And a dry mix (sand and cement) i find troublesome.... you tend to dip the corner of the slab into the sand, and make a dent, and then have to lift it and brush sand around.. etc.

 

[J_N30]

From what I've read on here a semi wet is ok upto 450x450 slabs. Always make sure an open edge is a wet mix though.

 

[r896neo]

getting the bed right first time with a dry mix is very hard and if you relay the slabs a couple of times you have done twice the work.

It is better from the point of view that it's cleaner to work with and less likely to stain natural stone etc.

Laying on a wet bed is much easier to get right and will give a far superior result for a diyer.

You can lay large format paving on a semi dry mix but you need a magnet etc so is impractical for small domestic projects

 

[JohnD]

a magnet?

 

[r896neo]

Stone magnet/ suction kit hung off a mini digger etc as you need to bring it down level.

 

[ConcreteDrBill]

If you lay the slabs on a semi dry mix such as Slablayer, its a good idea to dampen the underside of the slabs just before you lay them. It stops them sucking moisture out of the bedding and improves the bond