Risk of bridging DPC Drainage pipes, concrete, footings and foundations. Post your questions and find answers here

[Buster9]

I want to pave a large patio area which is at present a concrete slab. The slab is 2 courses below DPC and I understand that this level should be maintained. I intend to lay 38mm paving slabs using spot morta but I do not know what to do about maintaining the DPC level running along the building edge. Can I put some sort of channel or other method along the wall - say about 4" away from the wall itself so that rain cannot splash over the DPC. Hope this makes sense !

Any advice would be very much appreciated.

[Perry525]

The best bet is to dig out a channel along side the wall, making it deeper than 6 inches below the dpc and at least 12 inches wide.
If you then cover the bottom of the hole with small round stones and watch when it rains, you will see that the rain doesn't bounce, when it lands on the stones.