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Damp Proofing

I have mould under my windows,where is it coming from

My window sills have water,possibly from the condensation,but under neath I am getting about 1metre area of mould.Is it from the windows.

2 Answers from MyBuilder Damp Proofing Specialists

Best Answer

Hi Gary,
You obviously have a condensation issue, which will unltmately lead to mould growth. The moisture in the air is attracted to the cold spots in the walls/windows and turns to water particles as it comes into contact with the colder surfaces. This condensation of water is what allows the mould spores to thrive.

If the windows in question are on the ground floor then there is the additional possibility of rising damp in addition to a condensation problem.

Firstly look for ventilation. There should be ventilation in each room. If there is none, this is your first problem. I would recommend passifyer vents from Sovereign Chemicals Ltd. These vents reduce draughts but allow the house to breath. They need core drilling which is messy and labour intensive. The walls then need rpainting with paint which has a specific additive to combat mould growth.

I could go on and on but you are better off contacting a soveriegn approved contractor like ourselves to do an assessment. They shoudn't charge for this.

The work is not cheap unfortunately and you may find that you have damp as well as condensation (as I said, assuming the mould growth is less than 1.5 meters from ground level). It is worth noting that the industry accpeted standard is that rising damp cannot travel more than 1.5 meters from ground level.

You may also have an additional problem: If the area outside of these windows has roofing tiles alligned vertically like a kind of cladding then this area will only be single skinned brick work. This will be creating a cold spot and attracting the moisture as mentioned above.

Double glazing and PVC doors stop natural ventilation, and people often cover up the vents on walls when they get the properties plastered over the years. These things accenuate condensation and mould growth.

Again, call in an expert. By all means tell me what prices they give you and what they suggest and I'll advise if they are trying to take you for a ride.

Kind Regards

Degan Building Services


Answered 9th Feb 2012

Hi , I agree with Degan Building Services , He knows his stuff, however You can buy passifyer vents from other sources and these do not require core drilling as they are rectangular therefore can be drilled out with very little mess .


Answered 11th Feb 2012

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