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Damp Proofing

Mould in walls caused by poor ventilation and insulation and type of heating system?


My boyfriend and I recently moved into a house we bought. It is quite an old end-terrace house, likely built in the early 1900s. Mould is starting to appear in places, especially in the side of the house which is the end-terrace (i.e. the far wall of the end-terrace) as the walls in this side of the house are often cold to the touch. We didn't really notice the mould patches when we viewed the house (three times) as the previous owner painted over them. However, now they are starting to re-appear.

I don't think that this is a penetrating or rising damp problem as I cannot see watermarks on the bricks where I've pulled the wallpaper off. I think this is just a ventilation and insulation problem, but being a novice, I am not so sure.

Also, we have a heating system which is composed of a regular heat only boiler that has a separate cylinder and a water tank in the loft. I think that this system is indirectly contributing to the problem. The cylinder is located in the smallest bedroom and the mould problem appears to be worst here. A few days ago, I noticed that the room was so humid (while the rest of the house wasn't) and the humidity left when I adjusted the operation of the cylinder (so it's not on all the time). The pipe that releases water (to get rid of the pressure) from the water tank in the loft also keeps on dripping and there is a wet patch on the ground at the side of the house due to this.

I don't want the problem of mould/damp to get worse, so I thought that three things may need to be done:

First is to change the heating system into a combi boiler so that the cylinder can be removed and the water tank disconnected. This is to reduce the differences in temperature in the different parts of the house. British gas also has a boiler scrappage scheme offer which we might take up to reduce overall costs.

Second is to insulate the far wall/end=terrace side of the house with some insulating plaster boards, but before that, clean up any mould residue otherwise it might create problems in the space between the wall and the insulation.

Third is to increase ventilation. I don't know how complicated it is to increase ventilation in the house that doesn't just involve opening windows.

Can anyone please advise on whether this approach is the best or if there is a different way of tackling the problem? Since we just bought the house, we cannot afford to spend a lot of money in renovations/repair work so we need to start with the essentials first.

1 Answer from a MyBuilder Damp Proofing Specialist

Best Answer

Hi there my name is Jim. First. You need some new air bricks and at the same time clean out the cavity. Second. you have to remove the mould with some mould clear. Third. Open windows for one hour a day to let some ventilation in.


Answered 5th Feb 2015

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