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Damp Proofing Question
We had a problem with a leaky gutter causing the inside wall to be wet and damp. the gutter was fixed 8 months ago but the wall is still damp with mould growth. please advise how to fix.
In additon the house suffers from mould in other rooms which we believe to be a result of general dampness in the flat (possibly as a result of the damp wall).
The flat is a sandstone tenemant and we are on the ground floor.
Condensation sounds like your problem...... Improve the situation by reducing the humidity (moisture in the air) by ventilating the property well (keep windows slightly open on the locked latch at a minimum at all times)and keeping a constant low level of heating on at all times (rather than timed, sporadic bursts). Fully open kitchen and bathroom windows when in use and close doors to the rest of the property (and for at least an hour after to clear the condensation). Don't dry washing in the property on clothes horses or on the radiators. Keep a window open in rooms when in use.
In severe cases, passive pressure units (push low levels of clean air through the house constantly) and more effective extractor fans in kitchens and bathrooms can also improve the problems.
If problems persist, wall insulation can also help improve the situation.
Answered 1st Dec 2011
Agree with DSL - once plaster has got damp it will continue to absorb moisture - if it is not drying out by itself then it will require removal and render to be applied as per the spec above with a waterproof additive.
Ensure you get a damp expert to replaster or follow the specification carefully otherwise the problem will not get resolved.
Answered 14th May 2012
have you tried a dehumidifier in the room?? They can be hired from speedy hire etc
Answered 15th Jan 2013
Once the Plaster has got damp It becomes porous and take's in moisture
from the atmosphere. The best cure is to remove the affected area's and re plaster using sand and cement render with good water proof additive.
It would be a good idea, to fit a condensation unit which would help to
get rid of the condensation.
Answered 29th Mar 2012
Has the wall had cavity wall insulation that now (possible) causes the problem (The local authority will have a register of who done, when, and remaining guarantee).
Internal moisture (especially in flats - with no garden / cloth line) is often caused, by drying wet / damp clothing on or by radiators, and keeping windows close (A common winter problem).
Try to avoid this, plus vent areas when possible and check results after you have washed off any existing mould.
Answered 31st Dec 2014