Terraced house kitchen floor damp issues

[Montybuoy]

I live in a 1906 terraced house undergoing a full kitchen rip out, down to the brick. The kitchen floor is quarry tiles over earth with no sign of any damp proof membrane/insulation. There is a ¾” gap, about 1” or so deep, between the walls and the floor tiles and the ground in that gap is very damp. The floor is also uneven and I’m considering using a SLC after I get my concerns about damp sorted out.

I realise I need to get a DPC to prevent rising damp and this will go in above floor level. I’m concerned about the damp below the dpc – the skirting I pulled off was very damp and I want to make sure that I can prevent this happening to the replacement skirting and avoid problems with damp in the future.

Some DPC contractors have looked and advised either tanking the walls or laying asphalt on the floor. If I can avoid it, I’d rather not do a complete dig out and fit insulation and a DPM but I am looking for options, and opinions on tanking or asphalt. or anything else that will work. If I do apply asphalt and go right up to the walls, am I likely to be creating future problems, and if so, what? If I apply tanking, how do I treat and/or fill in the gaps? (I've tried raking the gaps out but not very successfully).

Hoping somebody can advise. Thanks in advance.

 

[vinn]

If I understand your post then the best practice option for you would be to dig out the floor to an appropriate depth, & and pour an insulated slab over a membrane (DPM).

The idea that you can leave the quarry tiles bedded on earth without damp consequences is well wrong.

Why not post pics of the walls and floor as things now stand - & pics of the exterior?

Research similar posts on here, and maybe supply further helpful information such as the outside ground level, and what kind of walls you have etc?
I'd find it impossible to accurately help you without quite a bit more information.

 

[Montybuoy]

Thanks, vinn.

There is so much advice here and elsewhere that I just get confused! My main concern is identifying the types of problems I might encounter down the road depending on what course I take now.

I'll upload some photos when I get a chance but for now I can say that ground level outside is about 6" below kitchen floor level (more accurate measurements when I get back) and walls are 9" brick. Internal floor is not level and in places is about 1" below the blue brick course and in other places comes half way up the blue brick course.

On further investigation, I've found that previous owners concreted over some of the quarry tiles towards the end of the house, probably to level the floor - photo of that area is attached, and a view of that area from above with quarry tile edge sticking out circled. This area was tiled down to the floor.(Someone also clipped cables through the middle of a gas pipe - yes, really - so you get a feeling for what I'm dealing with here!)

 

[vinn]

The gap is merely the difference between the quarry tiles and screed, and the sub-floor and wall.
Where is the quarry tile over earth - please show earth?
The blue brick course is your DPC.
Is the exterior rendered?

"towards the other end of the house" means nothing to me in terms of location?


You must not run cables in any area except the designated safe zones.
Any suspect abandoned gas pipe or water line must be investigated - they cannot just be left as is.

 

[Montybuoy]

Thanks for the advice about the gas/water. The gas pipe the previous owners nailed through wasn't abandoned - it was live. I've been living in a time bomb!
Re the floor, there's no rendering outside and the damp in the gaps between walls and floor is against internal and external walls alike. Photo of tiles on the earth is attached; tiles are on 1" or so of mortar and the earth is directly below the mortar. Hope this gives sufficient info to help people to advise.

 

[vinn]

My original suggestion for lifting & replacing the whole floor still stands.
The wood skirting plugs in the walls should also be removed.
Rotten skirting would suggest that rising damp might be by-passing the blue brick DPC course.
FWIW: you might try injecting Dryzone into the blue brick perps and beds.