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Hi, im advised to install some air bricks in my flat due to some mould growing at the back of the cupboards, in the bedroom. Im going to have 2 installed.

Can anyone advise me where is the best position to have these air bricks? One at the top and one at the bottom corner so air can circulate? Or shd i jsut hv both at the top? The moulds are growing from the bottom.

Please advise!!!!

Hi lin,
Airbricks are usually fitted in the rooms which are the most humid, eg kitchen and bathroom.

Have you considered opening a window instead of fiitting airbricks. You can always shut a window when it is windy. Not so easy to shut an airbrick.
An open chimney flue also helps reduce condensation.

I share a bedroom with my wife, and we open a small, vent window each night and close it in the morning. We have never had any damp.

Unless you are a single lady sleeping in a downstairs bedroom and worried about security, I would try the window option first.

There are many threads about condensation in the Damp forum. That is the place to ask you question if you choose the airbrick route.

Are you on the ground floor ? wooden floors ? If yes then you need to provide ventilation to the floor void. There should already be air bricks there - so might just need clearing.

If it's an upstairs flat, most houses - in bedrooms - have air bricks at the top - ceiling height. So i'd go with that.

yes, im a single lady on the ground floor flat. So opening the window .. im afraid is not an option.

It's also wooden floor, but for some reason, no one installed air bricks .. so ive got moulds growing at the back of the walls. Ive got some advise from Kenwood, and they suggested air bricks. However, their quote is ££++, so ive got someone else, however, he wanted to know if i wanted to put it at the top of the wall, or at the bottom. Can u help?

Hi Lin,
The air bricks that htg engineer refered to will only be seen from the outside of the house. They are to provide an air flow under the floor. I hope you have these assuming you have a suspended wooden floor, as you are likely to get dry rot if not. However, with wall to wall carpeting they do little to ventilate the actual room.

If you fit an air brick then I would choose to have it near the ceiling rather than at skirting board height. Less drafty if placed higher.

Just a thought, many modern double glazed windows have a two position locking catch, so you can lock them open about half an inch. I recently pointed this out to a lady in a similar position to you. She had no idea that this feature existed. Also newer windows should have a built in trickle vent which you shold leave open all the time.

If you own the flat might be worth getting a quote for replacing the window.

Thanks Kenj, you are right, the double glazed window can be opened abt 1/2in and its pretty secure. I didnt know i could do that!! Just had a play with it. The top latch is always left open, altho ive notice green moulds are beginning to grow at the top 2 corners of the windows :( I guess its all down to the lack of air circulation.

The management company in the building has advised us to install air bricks as all the owners/lodger of this property had the same complains each time. So they are now wanting us to go ahead with it.

Would you advise me to have an air brick install nearest to the mould - ie. at the bottom, and then one installed at the top on the other side? Would this increase air circulation?

Hi Lin,
I am no expert on damp & condensation so would not attempt to suggest where or how many air bricks to fit.

I would suggest however, that you install air bricks as a last resort only. Try leaving your bedroom windows locked open day and night. Open a vent window at night if the vent is too small for anyone to climb through. Leave your bedroom door ajar at night. Fit an air vent to the cupboard door where the mould occurs. Buy a dehumidifier.

There is some very good and detailed info on this subject by perry525 in the similar post in the Damp & Damp Proofing forum, which you have already visited.

This post also said that there was a very good leaflet on damp and mould available from Richmond upon Thames council. To view this simply do a Google search for " richmond upon thames damp and mould ".
Why this information was censored out, is completely beyond me.
It takes hours to get a post through, then harmless infomation is censored by the Moderator. I have just about had it with the DIY Doctor forum.
So I'll say goodbye now.

See our projects section and look at the project on condensation. Also see any of the damp projects and phone the company advertising in there for free advice. We have worked with them for years and they offer free, no obligation advice.