DIY Doctor UK DIY Forums

I have a problem with moisture below floor tiles and laminate flooring in the extension of my house.

The extension is a timber frame and I do not believe there is a DPC under the concrete although I have no way of verifying this.

After removing tiles in the utility room there was moisture underneath them. I thought this was from a leaking washing machine so I let the floor dry out. Whilst the floor was drying out I noticed if I left an object on the floor and moved it a bit later there would be a damp patch underneath. Now I have had lino fitted and this too is lifting.

I am worried if I lay a membrane down on the concrete it will trap the moisture in. I know there are treatments for concrete to make it waterproof but would this mean everything underneath would be damp?

I don't even know where to start or who to ask to be honest so if anyone has any ideas I would be very grateful.

you can lay a cement based waterproof grout/ slurry on the floor, cementone is one product, try your local builders merchants

Ah excellent, I was hoping it would be something simple like that. I had visions of smashing up the floor! Is this quite a common thing to happen on these type of floors? I believe the extension was built some time in the late 80's/90's