removing old concrete floor

[sarahj]

we had a nasty looking bump that ran the length of our entrance hall in our stone cottage. This had been covered by carpet (nailed down) by the previous owner. we lifted it up to find that the concrete had split and the smaller piece was sunken. In for a penny in for a pound we therefore dug it up to find no tree roots or anything else apart from a very small amount of dampness which had rotted the skirting board along our neighbours wall. As we are lower than our neighbours that is to be expected. Also the cement plaster was right down to the concrete which was up to the edge of the wall with the skirting on top. The tongue and groove partition is covered in wallpaper but now is revealed in all its rotten and wormy glory.

The concrete appears to be very old, no dpm, and only 3 inches thick. Underneath is lovely golden sandstone rubble. I am hoping and praying that it is the same in the living room so that that can be easily dug up as well (there was a 1980's extension and I expect that the concrete there will not be so moveable).

My question is:

How easy would it be (for easy read 'unskilled') to put a flagstone floor down on top of this rubble? we are on the side of a hill where the springs never dry up so there is a lot of water travelling under the house so breathability is extremely important, although it doesn't seem too bad in spite of the cement plaster and concrete floor.

 

[NT]

Why do you want to pull the living room floor up? (looks confused)

NT

 

[sarahj]

the living room floor (also concrete) is has a large hollow in front of the inglenook and has been taken right up to the edge of the stone walls where it is also deteriorating with the damp. The cottage (originally one up one down) was built in 1837 of lovely ashlar stone on the side of a much bigger house. Sometime in the past the stone flags were removed (and are to be found all around the garden) and replaced with concrete. I would love to have a floor more sympathetic to the property, but I wasn't going to consider removing the concrete if it was the modern stuff - thick and hard as iron - but if its older, thinner and softer (which would explain its deterioration) I would like to look at doing whatever is the right thing to minimise the damp.

we have not taken any notice of the recommended chemical dpc in our full survey, but we are removing the soil from the front of the house (although the lovely old plum trees right up against the front wall giving our cottage its name will have to stay). we have also had the front repointed in lime and new guttering (the old was plastic and falling off). We also installed a wood burning stove (there is no other heating). It seems that the modern plaster taken down to floor level is something we can easily remedy but I would welcome any suggestions. We are trying not to do too much at any one time as we cannot afford to move out, but we might be able to remove plaster over the winter in time to use lime in the spring.

 

[Sue Wilkinson]

It sounds to me like you are doing the right things. Going slowly and not in a rush for a start. Then removing the damaging materials and replacing with more suitable stuff.

I too would take the concrete up if possible, at least in the old part of the house. I recently hired an SDS drill and found this excellent for breaking up the old render on my walls, and for breaking up a bitumen floor to remove it and reveal the original floor underneath.

Once its out, I don't know how to advise you to lay a new flagstone floor, but it can't be that difficult, just heavy. If you already have rubble down. However, if you get the concrete up, take up a section of rubble too, just to see what's under that. It may have been put down just for the concrete and be hiding something even better. I believe flags were originally just laid on the earth, you could replicate with sand for a level finish and then joint up with lime and sand. Don't end up sealing the flags though.

Sue

 

[mark_j_k]

I've got to lay a flagstone path is a garden soon, I've found some useful information at http://www.pavingexpert.com/york01.htm
I think the principal would be the same for inside but I'd check first.

 

[NT]

It the floor is removed entirely, I'd be wanting to put dpm and insulation down before the flags. Flags on earth will only dump a load of moisture into the property. And insulation is worth it, responsible, and wont be visible. Sometimes modern tech is better.


NT

 

[Moo]

I have flags on earth, and pamments ditto in my breakfast room. No dpm, no sealant, no damp.

 

[NT]

Theres a difference between damp and damp problem. What you have is no damp problem. But any floor material laid on (damp) earth, unless impermeable, will allow evaporation of damp from the soil into the air. This increases interior RH and makes a damp problem more likely or worse. Any one of us may be just fine with one, some will but some wont.

There are of course other ways to reduce damp than a dpc in the floor, such as a layer of gravel under it all.


NT