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Damp Proofing

Damp patches and mould appearing on some walls

Having been in the property for some 6 months now, we have been noticing over time that there ARE damp patches and mould appearing on some walls, around windows and on the concrete floors. Can anyone please give me some advice as to where to start in rectifying some of these issues?

3 Answers from MyBuilder Damp Proofing Specialists

Best Answer

This sounds like condensation especailay if you have streeming windows and black spot mould spor patches.

The cause:
The cause is moisture in the air from eather cooking bathing even breathing as an adult produces near 1 ltr per night and that vapour will enitaily go to the coldest areas of the room's ie windows, gaps in exterior mortar/render which alow in driving weathers, missing or no insulation in loft and missing wall insulation and cold concrete floors

1.To warm the property by insulation, eficiant rads or insulated plasterboard to the interior external walls etc
2. Vent adequatly using trickle vents on all windows, passive vents on prone walls, extraction/humidistats in kitchens and bathrooms and in some servier cases we install a positive input ventilator with heat recovery (NUAIR PIV)
3. After work is completed use an adequate fungicidal wash to clear bacterior also use a stain block before decorating

All buildings today are prone to condensation as they are tightly compact using upvc windows, solid cold brickwork and no ventilation un like the old rikety buildings years ago.

I hope this helps


Answered 17th Feb 2011

Sounds very much like condensation. Do a little test, get a cold bottle of milk/beer out of the fridge stand it on the side, very soon the cold bottle has water droplets(condensation) on it ,obviouslly the water didn,t come out of the bottle, it shows that there is moisture in the air. The hotter the air the more moisture it holds (anything more than 60% is bad)
So in the winter months you have very hot air inside and cold external walls, hot moisture laden air meets cold surface CONDENSATION forms.
Now it becomes sceintific , mould/mildew spores are ever present in the air and attach themselves to wet areas these spores are asexual meaning the breed by themselves unlike normal plants that need germinating ,
So the the only way to cure the problem is to cure the air (input ventilation) not extraction.
Best cure by far is a Heat recovery ventilator
Hope this helps Steve


Answered 20th Feb 2011

In addition to other comments try a mould treatment kit to help you keep the mould/smells away. If you can paint a wall, you can apply the mould kit. available from most DIY shops.


UK Management Builders LTD


Answered 17th Feb 2011

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