No Damp Proof Membrane

[andrew5235]

I hope that somebody can offer some advice so that I can decide if it is a job I can tackle myself or if I need to get somebody in, what I should be asking.

I have a late 1940's semi-detached bungalow with a concrete suspended floor. In the last 2-3 years we have been getting damp issues in various places in the house. I have been looking into it and suddenly had a spark of inspiration that maybe the damp was just coming up through the floor.

So today I have had a chance to inspect and excavate the sub-floor and have found that there is no damp proof membrane or concrete solum or oversite. We live in Scotland, on a clay soil and there is evidence of effervescence on the surface of the sub-floor.

Therefore I would like to remedy this and wonder what the appropriate work should be? Should a DPM be installed on the subfloor, or could I attach it to the underside of the concrete, or some combination?

I also noticed that the concrete feels warm to the touch and so wondered about adding some insulation slabs and maybe this would also provide some moisture resistance.

Any questions, let me know and thank you.

 

[^woody^]

I can't see how you can have damp coming through a suspended floor

 

[andrew5235]

Thanks Woody, if you have damp clay soil and nothing to stop the moisutre transfering upwards, I would have thought that could be contributing. Otherwise, why do more modern houses with suspended floors have damp proof membranes and concrete laid on top of them?

There are air vents but a modern house would have no more air vents than I have with out a dpm.

It is a recognised problem, I just need to now how best to fix it.

 

[^woody^]

Suspended concrete floors do not have a DPM. Nor do they touch the ground below, otherwise they are not suspended and there is no way to ventilate the floor void