DPC when building off slab on piles

[Wiredcharlie]

I want to build a single room extension. Due to the ground conditions it needs to be on piles. I reckon it would be cost effective to cast the floor and edge beam in one go as a reinforced slab. However, this would not have a damp proof course because of the piles.

I figured I could do a floating floor:
slab->polythene sheet dpc->TF70->chipboard

But I can't quite figure out how this works with the wall as any water running down the cavity ends up at the same level. To make things even more awkward I was thinking of using a timber frame with brick skin.

I'd be grateful for any help!

Tony

 

[stuart45]

All of the sites that I've worked on with piled foundations had a ground beam ( either insitu or pre-cast) and the floor put in later, often block and beam. If you want to cast the 2 together you might be able to use the method used on raft foundations where the edge of the beam is a toe, making the face work and the cavity is a few courses lower than the top of the rest of the beam.