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Damp Proofing Question
What is needed to make a cellar habitable?
Our cellar appears to have been half-converted by previous owners - some of the back walls have a black coating on them, radiators have been fitted and electrical points are down there. I'm just wondering what it would cost to finish the job - there's approx 6'3'' floor to ceiling height in there - we're not bothered about headroom as would just like to use it as a study. The floors are concrete, and there is some yellow fungus-like mold growing on some of the walls. We don't have problems with flooding and no big problems with damp (it just smells a bit musty). Previous owners carpeted it - before we had a new DPC for the house six years ago so not sure how much of the smell is just absorbed into the carpet. We would probably need a window well, or I guess we could install an exit point at the top of the basement stairs if we put a firedoor on the doorway to the kitchen. Just curious as to how much work would be involved/rough costs as we're not sure if it's worth taking the idea any further! Thanks for any help you can give us!
Its a very tricky question to answer as the cost could vary dramatically as there is habitable as in being able to use the room comfortably and then habitable in the eyes of a building inspector.
For it to be habitable it would need to go through building control and be inspected by building inspector during the renovation.
The head height may be an issue for it to be "habitable" this would need to be discussed with building control.
There is then the issue of the electrics are they upto scratch do they conform to building regs
The floor would need to have a damp proof membrane applied which would mean it would need to be raised which again is going to effect the head room.
It would need some form of insulation on the walls and ceiling.
The fungus on the walls would associate some form of damp either in the walls or humidity of the air. (The fungus itself could cause some form of health risk)
The black coating on the wall could be some sort of bitumin type tanking membrane to prevent damp.
If the room is going to be habitable or not i would still expect you are going to be paying a couple of thousand pounds.
Answered 20th Feb 2011
Hi, Firstly you would need the basement walls and floor tanked, this is a water repelling seal that keeps out damp and seals the whole area, even if you have no signs of damp the musty smell and fungus are a sure sign its damp anyway, i only know this as i had my basement done in my previous property and it cost me £2000 for a basement size of 18x10ft, with good light reflective windows and ventilation it turned out to be a great additional room! Hope this helps, Paul
Answered 21st Feb 2011
The fungus growing on the wall would most likely be prevented by new tanking being applied to all walls, as well as specialist plaster, if required. Also it would be wise to dig the floor out and relay with damp membranes and possibly insulation under the new concrete floor. This could be up to £1000 worth of work. Ventilation is also key in damp areas, so some sort of ventilation (possibly extraction fan) would be recommended. If you would like it to pass as an extra room, building control would have to be contacted and depending on what they say could affect the price considerably.
The best course of action would be to either set a budget and contact some builders, or contact building control and have them set out requirements then send those to a builder for an estimate. I hope this helps, regards, James.
Answered 21st Feb 2011