Concrete Floor

12 Jul 2009
Reaction score
United Kingdom
My cottage was built in the 1800's and has what appears to be damp coming up from the concrete floor into the surrounding walls, the top has what looks like asphalt on it, I want to completely dig out my concrete floor and replace properly.

What layers, depth, insulation etc would I need to do a proper job?

Your advice would be appreciated

Sponsored Links
Generally -
100mm hardcore
50mm sand
DPM (to spec)
Insulation (to spec)
100m concrete
25-50mm screed.

Can't see the need for an engineer either.
Sponsored Links
The problem that you have is that even if you replace the floor, because of the DPM the damp will still be sent up the walls.
I've got this problem in the kitchen, and this is a common problem with the old cottages round here. The old flagstone floors allowed the damp to breathe out through them.
An option is to replaster the walls with lime to allow them to breathe better.
I agree, we have been asked before to help with problems like your own, digging down and replacing could be very risky as old properties were not built on foundations like todays, depending on your location it could be built on sand or clay. if the sand has eroded or the clay had dried you will now have shrinkage around your stepped footing. Removing any concrete, may let the footing move.

As was said earlier. you may want to have a reputable damp company take a look, a quote is usually free unless a survey is required.

And which damp companies have a good reputation ?

How many people requesting a survey have ever been told it's a leaky gutter or cracked rendering repairing rather than 3K of damp-proofing they need ?
Well if you dont trust any company then its time to call in an independent surveyor
I have not dug out anything yet and the internal brick supporting walls do look dodgy to say the least, the bricks are spalling badly

The property has not got a DPM anywhere in the building and where I
have replaced bricks at ground level it appears it has no footings either and has been built on solid clay!

What steps would I need to take or is it a bigger job than I thought?

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local

Sponsored Links