Damp proof barrier

[asalcedo]

I am going to keep in storage several household items in a basement where the floor is the land soil, i.e., no concrete slab or other flooring.

What type of damp proof barrier or membrane should I get to reduce the moisture ingress from the floor?

I've been looking at the Screwfix range, like 'Damp-Proof Membrane Black

4m x 25m 1000ga | Screwfix.com'

or

'Vapour Barrier 2.5m x 20m | Screwfix.com'

I do not know if those are appropriate for the job (some reviews mention usage to keep the rain from a roof)

Other parts of the same basement do have a reinforced concrete slab as flooring. Is it also a good idea to use a damproof membrane on top of the concrete floor?

Thanks,

Antonio

[andrew]

Apart from the likely problems with condensation and mould why not use a

12.5 metre by 4 metre roll of damproof membrane, 250mu should be ok and about 30quid, mind it's slippery to walk on though.

I'd probably raise them off the floor on old pallets.

AJH

[Dave Liquorice]

It will be damp no matter what you put on the floor. What ever you intend to store down there needs to be damp tolerant but not many things are...

A DPM will stop the damp soaking into things resting on the floor if they are at porous but it will do very little for the damp in the air.

[Hugo Nebula]

Unless you intend to fully tank the basement, i.e., by sealing the walls & floor, and having somewhere for the water outside to drain away, then your basement will be damp.

If you intend to put stuff in your basement, a) make sure whatever's down there doesn't mind getting wet, and b) make sure the basement is well ventilated to allow whatever's down there to dry out when it does.

The membranes you linked to are variations on polythene membranes to stop moisture from the inside getting into a structure that would be affected by it (i.e., a timber frame or a roof). They are not enough to keep a basement free from damp by themselves.

[asalcedo]

The humidity in the basement is high, between 65 and 80 %

However, it is fully water sealed. I've kept other things in storage there for long periods of time, but in the area of a concrete floor.

I am now thinking of using the basement area with no floor.

I am thinking that covering the soil on the floor with a damp proof membrane will help reduce some of the moisture directly evaporated from the floor. This is what is recommended for motor vehiches in storage.

[Hugo Nebula]

If you're in the UK that's about normal for, well, everywhere.

You may be lucky and the place is not subject to a high or variable water table, and it is well ventilated.

Probably. It'll reduce the moisture rising directly from the soil to the upper surface, but it'll condense on the underside of the membrane. It will still evapourate into the air. But hey, you seem to have made up your mind what to do, so good luck.