Unusual solid floor - information sought!

[Dougal2345]

I've just rolled back the edge of the carpet for the first time on the solid ground floor of my 1970's house and am slightly baffled by what I've found.

On top of the black plasticky damp proof layer are wafer-thin (about 2mm), brittle grey-coloured tiles. They have very fine gaps between them which have no grouting; I can see the black damp proof layer in between. There is no 'screed' as I understand the term.

Does this floor design have a name, so that I can Google it and find out more?

I have no damp problems that I'm aware of, but am concerned that, as gripper-rods have been tacked down in several rooms, the tacks must have penetrated the damp-proof layer all over the place. Will this cause problems in future?

The reason I've rolled back the edge of the carpet is that I'm having some new patio doors installed in a couple of weeks' time. The wafer-thin "tiles" are quite badly broken-up near the current doors, leaving the black damp-proof layer visible. I imagine when the new doors (with new cill) are installed, some kind of sealant will be applied between the damp-proof layer and the new cill, so that will be okay. But is there anything I should do (before or after) to replace the broken tiles? And if I take up any of the gripper rod, will this open up the holes made by the tacks and cause problems?

 

[flooringman]

What you have is "Marley" type tiles laid into a bitumen adhesive. This is not a dpm as such but will suppress some moisture in the sub floor.

In all probability (judging by the age of your house) you will have a dpm underneath the concrete sub floor and the gripper nails will only damage this surface and break up the tiles.

If you are going to put the carpet back down I would'nt worry too much including not bothering to replace the damaged tiles.

 

[Dougal2345]

What you have is "Marley" type tiles laid into a bitumen adhesive. This is not a dpm as such but will suppress some moisture in the sub floor.

In all probability (judging by the age of your house) you will have a dpm underneath the concrete sub floor and the gripper nails will only damage this surface and break up the tiles.

If you are going to put the carpet back down I would'nt worry too much including not bothering to replace the damaged tiles.

Thanks for that, it's put my mind at rest! I thought I was looking at massively expensive repairs for a while there

 

[Dougal2345]

Just going back to this, I've noticed that at the point where the concrete floor meets the outside wall at the base of the patio doors, there are lots of little holes and gaps (see picture), which could well be the route that the neighbourhood ants took when they invaded this summer.

Untitled

• Dougal2345
• 7 Nov 2009
• 1

What would be the best way of smoothing and sealing all this mess? It would be nice to have some kind of liquid sealant that would actually run down inside these small holes and cracks before solidifying.

The carpet that I've rolled back, when the new doors are fitted, won't quite reach the new doors (the old doors had secondary double glazing, removed in this picture, and the carpet had been cut to reach the edge of that - note the large gap between door and gripper rod).

So I want to put a strip of lino in the door recess and cut back the carpet so that it doesn't enter the recess at all.

So any advice on: (a) sealing the holes (b) getting a smooth surface and (c) fixing lino on top - would be gratefully received.

 

[flooringman]

I would suggest a piece of timber - cut to fill the recess. Use a silicon sealant to fill any gaps and then drill and plug the timber in place. Stain and/or varnish and run the carpet up to this which would then be flush to the wall.