Slightly damp concrete

[samwich]

Hello, I have another question!(I know nothing!). The kitchen floor is slightly damp in places and I'd like to tile it. Before tiling what's the best thing to do?Tank it in the trouble spots?Use Ditra matting?I'm confused about these waterproofing products - I know they stop water reaching the substrate but do they also tackle any damp problems the other way round ie stopping the damp substrate affecting the tiles?
Thanks v much for any advice, I've been trawling the forum fo 2 hours but still haven't found what I'm looking for!
Bono

[Schlüter-Systems Ltd]

Schlüter-Systems Ltd’s technical helpline would be more than happy to help you with this query. Contact Schlüter-Systems Ltd for immediate advice and information on 01530 813396, or alternatively, e-mail technical@schluter.co.uk. Lines are open Monday – Friday, 8.30am – 5pm.

[samwich]

I've just called yourselves and been told you don't do damp proof membranes so can't help. Damn automated email responses!

[grumpygrouter]

Schluter do waterpoof membrane called Kerdi matting. They also do a product called Ditra matting which is similar to Durabase available from Wetdecs. These are "decoupling" mats which allow lateral movement of the substrate without affecting the tiled surface, another byproduct of this matting is that it allows moisture to evaporate out from underneath the matting.

You really need to find where your damp is originating from first and address the source of the problem. You could then lay one of these decoupling membranes and then tile on the top. This would allow any residual damp to dry out without affecting your tiled surface.

[whitebeam]

A damp proof membrane stops moisture entering from the substrate, A decoupling membrane stops moisture entering the substrate

[Dave]

Kerdi is a crack isolation and water proofing membrane russ and not an uncoupling membrane....

The kitchen floor is slightly damp in places and I'd like to tile it.

Do you know what is causing these damp sections on your kitchen floor....?

[grumpygrouter]

Kerdi is a crack isolation and water proofing membrane russ and not an uncoupling membrane....




Do you know what is causing these damp sections on your kitchen floor....?

Thats what I said Dave, it was Ditra/durabase that i said was a decoupling membrane.