DPM in new concrete floor?

[gdickin2]

Hi

I am replacing an old (Victorian) concrete floor in the kitchen with a new one due to break up and heave.
I have been advised (by a builder mate) that new revisions to regs now require a layer of DPM both above and below the inusulation layer, so now goes like:

Screed
Concrete
DPM
Insulation
DPM
Sand blind
Hardcore

Can anybody validate if this is actually correct or not and what the reason for this is?

Cheers[/list]

 

[DevilDamo]

I have never specified the insulation to go below the concrete floor, but it can be done.

My normal (suspended concrete) floor make-up is...

- Screed
- Vapour barrier
- Insulation
- DPM
- Concrete
- Hardcore

However, I have just looked at a u-value calculation carried out on the Celotex website and it doesn't mention the DPM between the insulation and concrete.

 

[freddiemercurystwin]

Sometimes you include an extra layer above the insulation to stop the screed seeping into the screed. The same result can be achieved by taping the joints between the boards though.