Thin paving slabs

[Clive Arthur]

I have a small back yard - about 20 square metres - which is a patchwork of different bits of concrete with cracks and weeds. I want to pave it, but I don't want to have to break it up, so I'm thinking slabs on top.

With the base layer and the slab thickness it gets close to the back doorstep level, but that's next to the drain and I can put a slotted drain strip thingy across the doorway at slab height. However, I still need the slabs to be fairly thin.

I see 18mm is available. This is Cornwall, so snow and ice is rare, but will they last? Any recommendations?

[R D S]

In my experience if you put a decent solid bed under them any slabs are ok, for walking on at least, none of them seem to like having heavy stuff dropped on them.

[Andrew]

Where is the house DPC though ?.

I would leave a channel about 6 inches wide along along the base of the outside walls and infill with pea shingle. This also stops heavy rain splashing up the wall.

[Jim Stewart ...]

indeed

[alan_m]

If the new slabs take the ground level above the DPC isn't there a danger in this case of the pea shingle channel filling with water, and remain there.? Exiting concrete beneath the pea shingle, concrete on one side (new slabs and the bedding of mortar) and house brick the other side. Unless there is a slope to the channel allowing water to drain away or the existing concrete beneath the channel broken up /removed (or holes drilled for drainage etc.) a pea shingle channel may not solve a potential problem. This the side of the country with most rain.

[Clive Arthur]

Thanks. I've seen dire warnings about using thin slabs, but they seem to be from thick slab sellers.

As regards the DPC, I don't think there is one on this old granite house, but I'm wondering if using channel drains around the house walls would be a good idea? They're not very expensive and there are two convenient rainwater/surface water drains.

[Tim Lamb]

+1 for the pea shingle channel on 9" brick. Don't know anything about Granite. >

[alan_m]

Or possibly related to the (non-recommended) 5 dabs of mortar method of fixing