So... Getting new carpets fitted and the chaps came to the dining room -
which used to be on the outside of the house, and we think used to be
the original kitchen, but we reckon some 60 years ago an additional
covered alleyway was built outside it, making a corridor into the barn at
the side of the house which is now the kitchen... House is c250 years old.

Anyway, when we lifted the old carpet they found some blue plasticy
stuff under it (like very thin foam - like the sort of stuff you might
lay under laminate flooring), then about 3 layers of brown paper then
a cement floor.

And at a few spots the paper was damp and mouldy )-:

The damp appears to be in lines where the cement looks like it's cracked -
according to a local builder it's typical here to put a layer of cement
over old flagstones which are on dirt - no DPM.

House insurance won't cover any work on it - I guess we got cheap insurance.

A few photos he

http://unicorn.drogon.net/20100813_001.jpg
http://unicorn.drogon.net/20100813_002.jpg
http://unicorn.drogon.net/20100813_003.jpg

I scraped the paper up last night and it more or less immediately
dried. We've never smelt any sort of mustyness in that room, nor felt
the carpets being damp. It's been raining here today and there's no sign
of any dampness coming up...

(currently have some off-cuts covering bits of it and not noticing
any issues)

We think the old carpet was there for at least 15 years, and we suspect
they knew about this - there's also a few blobs of what looks like
bitumen over the floor too....

So... Bit stuck here about what to do - most thoughts seem to be that
if the underlay we're using is breathable (it is - local stuff made with
recycled tyres and felt) and the carpet is also breathable (it's hessian
backed) and wool, then we'll probably be OK. The amount of water that's
come up has to be less than a cupfull over the years, but since the paper
had plastic on-top, it's never been able to dry out. The walls are fine
- and there was even a lot of dry dust under the skirting boards where
they were sanded down 3 years ago - so I don't think it's quite at the
swimming pool level yet!

One suggestion we had was to put battons down and floorboards on-top,
with ventilation grids at the ends - and while that's do-able, it will
raise the floor, requiring some steps into and out of it (2 doors and
a set of stairs), but others have said just to carpet it anyway, or do
as previous did with paper and plastic, then the underlay & carpet?

Anyone seen anything like this before?

Any suggestions welcome...

Gordon