Air bricks blowing a gale

Hi.

I've been in this house for about a month. According to the previous owners, this little flat-roofed bungalow, built in 1961, recently developed a damp patch on the bedroom wall. They took out the concrete path alongside the house and put in airbricks in bedroom and sitting room a few inches above the floor. They blow a gale!

Before I bought the house, I had the damp checked and the report was that the house is dry. The one in the sitting room originally vented into the cavity, and has a sliding cover, which I've closed, which has helped. So far, there is no sign of damp in the corner.

The one in here (study-bedroom) doesn't. I put an old, large, plastic-covered blotter in front of it, moving it at bedtime, which helped, but with the very cold weather, have left it there most of the time, checking it for signs of dampness. It's been fine except on two occasions this week when there has been a wet patch on the blotter's room side while all around it is dry, but very cold.

My thinking is that this airbrick is causing more problems than it solves, in allowing very cold air to flood the warm room, leading to condensation.

I'm also going to have cavity wall insulation done, and it seems daft to do that and leave what amounts to constantly open windows in two rooms. I'm at home most of the time, so the heating is on all day. Another point to bear in mind is that I always have the bedroom window open at night.

Your advice would be very much appreciated.

cold external air does not cause condensation.

because it is cold, it holds much less water than warm air can.

condensation on the room side is caused by warm moist air from the room.

you can fit a hit-and-miss vent over it and see what happens.

Thanks, John.

JohnD said:

condensation on the room side is caused by warm moist air from the room.

Click to expand...

Sorry - what I meant was that the warm air from the room is hitting the extremely cold 'temp cover' that I've used, causing condensation.

you can fit a hit-and-miss vent over it and see what happens.

Click to expand...

What is a 'hit and miss' vent, please?

it has a slider on the vent allowing you to close it

Thanks! The one in the sitting room has one of those.

The puzzle for me is that the house was built 50 years ago and had only just developed damp in that corner a year or so ago.

The guy who lived here did tend to use a sledgehammer to crack a nut, and I'm wondering if this is one of his 'over-the-top' solutions to a problem that would be solved by leaving the small window on 'night vent'.

My desk is in here, so I'm here a lot, and it is a major issue, so your help is appreciated.

no surprise realy buld up to the wall above the damp proof course you will get dampness from water on the path and earth contact underneath
you should have 6" clear under the damp proof course

is there any air bricks under the floor assuming its not concrete l o l

The floor is concrete, and, like most houses round here, I think it's built on a concrete 'raft'. The paths had been there since the house was built, and would have been below the damp course but it was logical to take them out.

<Thinking> The new windows were put in a couple of years ago, which may have contributed to their problem, if they didn't leave a window open.