Pre-installing floor dpm....slab not laid for while

[WabbitPoo]

For reasons of family sanity, what I'd like to do is build up the walls for the new conservatory in advance of taking the old (smaller) one down. However that means I cant pour the floor slab until later on.

Is it feasible and, indeed, satisfactory, to incorporate a strip (skirt) of 1200 membrane at dpc level, and later on, seal this with double-sided tape to the dpm I lay under the slab, creating a continuous dpm into the wall?

 

[Bonni]

Building control like to see the DPM come up and onto the wall before laying the DPC and building on it. That's the official way or should I say, the best practise way. Also, it's easier access and easier to level concrete off the DPC course before building on the DPC.

But there's no harm in doing what you suggest because sometimes you have to remove floors out of a house in order to fit a new concrete floor with underfloor heating etc.. so putting the DPM into DPC is impossible. I would put a 25mm upstand of Kingspan along the outside walls below DPC and 100mm minimum Kingspan in the floor. Don't forget a thinner DPM on the Kingspan before concreting.