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Blocking vent brick in bathroom

Postby carbar » Wed Oct 26, 2011 1:58 pm


I am about to start renovating my bathroom. As part of this I am intending to fit an extractor fan above the shower.

On one wall of the bathroom is a vent that goes through the solid brick wall (the house was build in the 1930's) to a vent brick on the outside.

Given that I am installing an extractor fan, would it cause any problems if I blocked up the vent?


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Simply Build It

Postby welsh brickie » Wed Oct 26, 2011 8:26 pm

only time will tell,fit a hit and miss plastic sliding vent,keep it closed and if problems occur you can open it.
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Postby mathewleo » Thu Nov 17, 2011 9:43 am

Well according to my experience it can give you trouble in future. So best way would be is not to close the vent. But close it with maybe a wire gauge. May be a picture would help.
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Postby Perry525 » Tue Nov 22, 2011 8:00 pm

The problem with an air brick is, if you leave it unblocked there will be a howling gale of cold air forming a path between it and the extractor fan when the fan is running.

You will also have the problem that at times your warm air will be disappearing out through the air brick and at other times cold air will be sucked in, depending on which way the wind is blowing and how many holes you have in your home.

From 2016 all new homes will be built to Passive house standard that means as air tight as it is possible to make them. No airbricks or trickle vents etc.... NO HOLES!

Keep in mind that every time someone fits an extractor fan it has to find air from somewhere to expel and that means cold air is pulled in somewhere to replace your warm wet air that has been blown out.

This costs you, every time you have to warm this new cold air.

A better bet, is to fit an extractor fan fitted with a heat exchanger, this pulls in air that has already been warmed by the outgoing warm air, no drafts and maximum savings.
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