Take out air bricks?

mrtobs

Morning - thought I'd pick your collective brains! We have several air bricks in our (1970's) house - 1 in the living room, & 2 in the kitchen. Apart from them making things a bit colder, someone has warned me that the cavity wall insulation could get wet (don't know if this would be the case??). I think the living room one was because the house had a back boiler originally (not there now), so I checked with the gas engineer when we had our fire & boiler serviced & he said it would be ok to have them filled. Would welcome your thoughts though!

SOSAGES

filled mine in the front room ages ago
house has not fallen down or blown up yet.
also makes the front room stay warm.

00ec25

what height are these airbricks and do they go right through the wall into the rooms?

if low level airbrick then what is your floor made of, assuming floor is wood not concrete than and air brick that low is necessary to ventilate under the floorspace (and, incidentally, the cavity) to stop the wood from rotting

however it sounds like yours are the sort that ventilate inside the room rather than under the floor. "Normal" airbricks of this sort will NOT ventilate the wall cavity as the space between the outisde brick and the room brick should effectively be like a sealed tube. It is OK to block off these air bricks. All you are doing is stopping a draught into the room, the downside is you might experience higher levels of condensation as a result.

ormus

room air bricks are ok to block up, providing theres no gas appliances in the room.
(not inc RS type boilers).

be aware that condensation may become a problem esp in kitchens and bathrooms.

Chris_Michael

You have had some good advice there and I would agree with everything that has been said. I would think twice about blocking the vents if you dry your washing internally on radiators or on a clothes horse as this will increase the relative humidity in the house and condensation and mould build up will be much more likely. But if you must block the vents and are drying the washing this way then buy a dehumidifier to control the moisture. This will also have the benefit of making the air easier to heat and healthier.

Hope this helps.

Chris

ormus

or try fitting those sliding vent covers.

mrtobs

hi there - the one in the living room is probably about a foot off the ground (we have concrete floor). We do have a gas fire in the living room, but the gas engineer said that it would be ok to fill it. Not sure if the living room is sealed off, but the 2 kitchen ones weren't, as a load of the insulation spilled out.

David_Aldred

Hi,
Room vents should be ducted all the way through the depth of the cavity within the wall to the outside (think tube) rather than simply venting into the cavity. If the vents simply allow warm moist air to enter the cavity then there is a risk it will condense out within that cavity and cause localised dampness / mould. If the vents are correctly ducted all the way through the wall to the outside then this should not be an issue or cause problems with the cavity insulation.

The vents are there to give background ventilation to rooms which is even more important if the original fireplaces are no longer open hearths as these would have given 2-5 air changes per hour and also if double glazed windows have been fitted without trickle vents within their frames.

Rather than block these wall vents up altogether consider ensuring they are ducted all through the depth of the cavity wall and fit the controllable vent covers as suggested by others above. If you block them up altogether and then find condensation / mould becomes a greater problem you may have made matters worse instead of better with blocking the vents up, whereas controllable covers gives you the option to shut or open them as necessary. Kindest regards, David Aldred Independent damp and timber surveyor