Airvents in boarded up chimney YES or NO?

18 Dec 2006
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United Kingdom
We have a 1930's house that we are restoring and the fireplaces have all been ripped out by the previous owners. We plan to restore them at a later date, but in the meantime we are going to just plasterboard them in while we attend to more urgent matters around the house.

Now I was under the impression that a small airvent needed to be fixed in the boarded up chinmey to let air into the room and let the chinmeny stack breathe.

We are using a good builder who as done alot of good work around the house so far, but he has insisted that we don't need the airvents and the rooms and both the chimneys will be fine just boarded in without the airvent.

Can someone advise?
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An unused boarded chimney will mean damp, moisture & musky smell problems inside and around the chimney area if not ventilated. The rain can get in from the top and cannot dry out as well, so it's important to have a circulation of air flow
depends if the chimney has a cowl on top, if it is totally blocked from the top then yes vent, if it has ventalation on top and a cowl to stop rain coming down then is will be fine not to vent.

for fireplaces check out pendragon firepleces, we are doing the same, although it is difficult finding someone to install them, so do it well before the winter
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If it is open on top, moisture will still get in and condensation can still form in the flue, and without through-ventilation then it will not evaporate.

Any disused chimney should be vented top and bottom
^woody^ said:
Any disused chimney should be vented top and bottom

I also agree but don't really want to repeat the arguments of the previous thread!
vent it. if in doubt vent it. costs pence, even if you dont think its necessary (and it is) vent it!
as the guys have said, water or damp can manifest itself in all sorts of ways into the chimney breast. just because the top is sealed doesn't mean our tenacious little friend h2o can't get in.

historically, chimneys burn toxic chemical releasing products that eventually saturate the porous bricks, which if exposed to damp, will leave a tell tale signature on the surface of the chimney breast.

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