Mould caused by air-brick???

[number49]

Evening all,

I've got a problem with back mould around an old air-brick. There's no mould elsewhere on the wall, it's literally just on the face of the air brick and a little around it's edges on the wall.

We have no gas appliances in the room. We usually have the windows open daily and are aware of condensation etc so regularly vent all areas of the the house.

Is it worth sealing it up as it appears to be the cause rather than a cure for mould...

 

[JohnD]

no

where is the damp coming from?

when you looked at the outside wall, was the airbrick wet? Ground contact? Leaking gutter? Dripping pipe?

when you look through the holes, is it clear?

post some photos

 

[foxhole]

Air bricks are the cure for Mold, not a cause.

 

[Burnerman]

Is this an internal ventilator brick you are talking about, that passes right through the wall?
They were often installed to provide air for a room fire place, and were installed as regulations years ago. They aren't used now, but of course the air brick system for suspended timber floors is absolutely vital.
John

 

[number49]

Sorry for any confusion. It is a ventilator brick that passes right through the wall and approx 6-8" above the finished floor level

The raised floor has it's own air bricks ventilating the sub-floor void.

On the outside there's nothing obvious, no leaks, drips or ground contact. The only thing I can think of is it's north facing and also in a very corner shaded by next doors extension.

Our walls are solid and prone to rising damp but an injected DPC has seemed to prevent it so I'm none the wiser...

 

[Burnerman]

I think this is an air provision for any burning appliance that could have been in the room at some time....if it was mine I'd blank it off from the outside as cold air is coming in and causing condensation with the warm air inside.
Obviously any solid fuel or gas appliances such as back boilers must have a suitable air supply.
John

 

[foxhole]

Never block vents , they cannot cause mold , only prevent it. At low level you probably have a minor damp problem caused by splash back of rain or leaking gutter , whats the outside wall like ? Sealing the vent will increase the problem.
Opening windows does not provide enough ventilation for a hom you need open vents 24/7.

 

[AlanE]

What form of heating do you have?

If it is for instance a gas back boiler, or other open flued gas or oil burning boiler, then this vent could be supplying essential air for it. Block it and you risk Carbon Monoxide poisoning!!

 

[number49]

Our heating is by room sealed boiler located in a different room so not related to this vent.

There are no other appliances although I suspect it was for an old gas fire which was gone before we moved in.

I think splashback from rain is unlikely as it's so sheltered but it could well be damp from the garden wall which butts up to the house a few inches away!

 

[JohnD]

post some photos