1960s property with thermoplastic floor tiles and no DPC

beddo

New Member
Hi,
I've a renovation where most of the property still has the 1960s thermoplastic floor tiles. I've had a flooring company tell me they are effectively the DPC and this seems to track. The tiles were removed from the kitchen by a previous owner, there was damp under the cupboards and part of the concrete is crumbling and wet. Where a breeze block cupboard had been built for the boiler a felt bitumen DPC layer had been put under the bottom row of brick.

This leads me to going forward. I've had several people say to fill the uneven bit of the floor with sand and cement, put a liquid DPC on top then self level to finish.

Separately, I've had a flooring company quote for:
Grinding existing concrete
First fill Self leveller
liquid DPC
Second fill Self leveller

This seems like double the work with the leveller and unless they're grinding quite far down is going to raise the floor level quite considerably. Another tradesman said that this would have to be the case as DPC/leveller layers should be 50mm.

I'd like to be able to go back to people a bit more prepared with knowledge so I can make sure I'm not being ripped off or ending up with something that is half a job and going to cause problems later.
Thanks for any advice.
 
How can I best address the issues with my 1960s thermoplastic floor tiles and concrete dampness without raising the floor too much or causing future problems?
 
I can't give you professional advice but I can advise from experience.

It's a big job. Number one point is to ask what you want for the outcome.

For me, I wanted a level sealed floor for LVT in some rooms and carpet in others. I left the tiles in the carpet rooms and had them removed with epoxy DPM and self leveller where the LVT is going.

What I have discovered is numerous other problems.

1) the concrete base is completely wonky and not flat. I went with a cheaper quote that didn't include the grinding but wish I hadn't.

2) my damp issues were caused by two problems. One is drainage outside. There's no point in putting in a DPM if you're problem is being caused by water from elsewhere. Get that solved and let it dry out

3) Mine is a Taylor Wimpey build. It had a design flaw. The DPM in the walls is lower than the thermoplastic floor tiles. There was wood and plaster bridging between the damp concrete floor and the walls above the DPM leading damp to travel into the walls. I had to rip it all out and refill the gap between the floor and walls with a waterproofing mixture.

Your cheapest solution is to make sure that everything can breath and run a dehumidifier - I have a Meaco that costs 3p and hour to run.

Expensive solution is to have all the drainage professionally checked to make sure water isn't sitting around the brickwork, remove all the tiles, grind the floor flat (also removes the bitumen) and take some plaster off the walls. Put in a DPM across the board to tank the place and put it all back together.

Any specific questions you think of the I'll try to answer!.
 
How can I best address the issues with my 1960s thermoplastic floor tiles and concrete dampness without raising the floor too much or causing future problems?
The 60s thermoplastic floor tiles contain asbestos. What finish do you want?
 
If it's the floor tiles most companies used in the 60's they will contain Asbestos that has used a bitumen adhesive.
Floor tiles will have to be removed by a specialist company first.
Once that is done you have 2 options;
1. Black jack or similar alternative, 2 coats all Floor and base of walls minimum 2" up brickwork (first remove plaster/scratch at base of walls and fillet).
Then use a 2 part self leveling floor screed to minimise rise of floor level.
2. Break up existing floor dig down, new sub base, DPM, insulation, concrete and screed.

There are other options but that's the two I'd suggest, if it's your forever home go with 2.
 
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