Ian Middleton wrote:


A friend of mine did this in his house to make room for his office, trains
and Scalectric. Wooden flloor, insulation + plaster board and a nice loft
ladder. The one thing that ruined it which never did solve was damp and
condensation, even in summer when room was too hot to use. No matter how
much he tried, more insulation, a heater or two the walls/ceiling always got
damp and went mouldy. Paperwork curled, cardboard storage boxes came unglued
and went mouldy, trains and Scalectric stopped working due to oxidation from
moisture. So in his opinion a bit a waste of time. Did have slight success
after installing fans to draw air out at top of room to ridge vent, but only
made the room cooler in summer and still had condensation on non sunny side.

Finally a building inspector friend of his had a look and noted the
following:-
- Damp cause 1 was from moist air from house (due to breathing, cooking etc)
rising to loft and condensing on cold walls/ceiling.
- Damp cause 2 (when loft closed) was interstitial damp (spelling ?) caused
by temperature gradiant outside to inside. Never heard of this bfore being
mentioned but is quite common.

Solution is surprise surprise, do it properly.....
- Proper stairway and door that closes to reduce house air rising into loft
room.
- Proper insulation.
- Proper windows/extractor fan.
- Proper heating, extension of central heating to keep it warm in winter.

He ended up removing all the ceiling plaster board (+insulation) and
reverting back to a nicely floored loft space that had no damp problems.



Thanks for that..

As it happens we have a proper staircase up there and a proper door
already. There are three very old small looking 'porthole type' windows
which do open, just. There's also quite a nice windows in the gable end
(open and tilt type thing).

There doesn't seem to be any signs of damp anywhere but I've only been
in the house for a month, and the loft is like an oven!

I'll check out the insulation board etc and see how much it would cost.

Maybe I'll just take over the spare room instead!!!

Cheers

Alex