I have just bought a house and a part of it has an earth floor. I
have plans to change it in to a garage or possibly a liveable area. I
am keen to learn a bit of DIY and my first job would be to lay a solid
floor where the earth currently is. I have never done any work with
concrete before and would be grateful of any advice on the best way of
doing things. How deep would I have to dig? What are the best ways to
waterproof the floor? The walls are damp and someone has suggested
laying a ventilated floor, does anyone have any advice about this?


I'm not saying DONT lay a concrete floor, but you should be aware of
the implications.

There are two building techniques, the old one which was used in your
house amd which relied on the building materials being breatheable, so
any damp which got in on a wet day could evaporate out on a dry day.
That system worked very well for hundreds of years until carpets
became common.

Then was invented the new building technique which has been used for
the last hundred or so years and relies on impermeable surfaces like
damp proof courses to stop water getting into the building structure
at all. That system works very well too.

The problems come when you do a mix and match of the two and if you
have damp walls then I suspect that the old breatheable limewash
finish has been covered with a new impermeable emulsion paint, which
traps moisture until it breaks out in damp and desperation.

A concrete floor will not allow any moisture out, so any water will
move sideways to the nearest place it can escape, which might be your
already damp wall. Hence the infamous rising damp. So before
concreting the floor think about where any water will go when you do.
It would probably be a good idea to damp proof the walls now when they
have had a good drying summer.

Alternatively, you could go the traditional route which has the
advantage of being eco friendly and less graft for you - which is to
leave the floor breatheable. It doesn't have to remain as earth.
Pammet tiles bedded in weak lime mortar (which is breatheable) would
be fine too. Then strip impermeable layers off the wall, limewash them
and relax with damp problems solved. A purist, me. Or lazy.

Anna


--
~~ Anna Kettle, Suffolk, England
|""""| ~ Pargeting, decorative and traditional
/ ^^ \// lime plasterwork
|______| www.kettlenet.co.uk 07976 649862