Material required to re-lay paving slabs ?

[robgraham]

We had what I think is described as 'riven' concrete slabs laid some dozen years ago - concrete slabs that look like stone and are different sizes. The area immediately in front of the front door step has sunk over the years and can now become a puddle.

Before I lift these 'stones' to re-lay them to get a drainage slope, what are they likely to have been laid on so that I can lay in the right materials ?

Thanks Rob

[Stuart Noble]

I find it easier to use a dry mix when re-laying slabs. 10 sharp sand: 1 cement sort of ratio

[meow2222]

just sand

NT

[Stuart Noble]

But, as has been pointed out recently, ants may have a field day. I've never bothered with cement but I can see it might be beneficial that close to the front door.

[Rob G]

Thanks guys, - I remembered lying in bed this morning (why does this sort of thing come to mind at the most obscure moments) - about the paving slab website

recommends sharp sand for small slabs. It does raise the bogey of ants, etc., but we rarely suffer from them, so I'll take a chance on that.

Thanks again

Rob

[meow2222]

Yes, there's ants. But lots of slabs sit on sand just fine - whatever you want. Ground sinking is also a potential problem, and can often be prevented by mixing some dry cement powder into the soil before compacting and laying the slabs on sand as usual. But people rarely bother. Some preventions arent worth it. If however you have the ground sinking now, then adding some cement to it would be worthwhile. It can just be raked in then tamped firm. And if youve bought cement you might as welll add some to the sand, using it dry.

NT