air bricks and draughts.

PaulJM

Hello,

I'm getting a lot of mixed messages about this on the Internet, so wondering what the views are here.

We live in a 40/50s semi detached, in a typical gabled layout, with three bedrooms and a loft bedroom.
It has air bricks in the back room extention. .. which was done in the 80s, and in the 3rd bedroom.

When it's windy, it's almost impossible to keep those rooms warm. .. Must be costing a fortune.
Whilst researching cowls to try to stop some of the direct wind, a lot of people in forums reckon that air bricks are not specified now, due to lack of open fires, and vents on Windows.
If that's the case, as we have modern vented patio doors in the back room, are they necessary any more?

greyteam1959

My Dad has made some simple cover that block the air bricks up.
He fits them in the autumn & removes them in the spring.
Never had any issues....be doing it for 40 plus years

WestonDave

I'd be inclined to proceed slowly if you are thinking of blocking them off - possibly putting one of the vent covers that have sliding shutters over them. Whilst they are possibly not needed now for the reasons you state, you need to first ensure that there are no open gas appliances (e.g. gas fire) that could create a carbon monoxide problem with insufficient ventilation.

The other problem is condensation damp. If you don't have enough changes of air in the house the relative humidity will rise (due to activities like breathing, showering, cooking and drying clothes) and when that increasingly humid air contacts a cold surface you will get condensation which can lead to mould etc.

So on that basis if you are sure there are no gas or other open flame appliances in the house (if so then get advice on ventilation needs for them before doing anything) I'd proceed carefully perhaps by sticking some cardboard over the airbricks for a time to see what effects you start to see. If that seems OK then I'd go for one of the sliding vent covers because you then still have the option to open it from time to time if you decide you want more ventilation (e.g. at night in a hot summer).

PaulJM

Thanks, both great suggestions.

There is gas fire in the back room, but that room has vents on the windows.
I also have carbon monoxide alarm on each floor.
I'm more worried about causing damp in the timbers, the house is very dry right now (no wonder, it's like a wind tunnel!)
So if I can keep an eye on this like you suggest, maybe check the windows for condensation, that might work.

ic

http://www.toolstation.com/shop/p37571

Furts

PaulJM wrote: »

Thanks, both great suggestions.

There is gas fire in the back room, but that room has vents on the windows.
I also have carbon monoxide alarm on each floor.
I'm more worried about causing damp in the timbers, the house is very dry right now (no wonder, it's like a wind tunnel!)
So if I can keep an eye on this like you suggest, maybe check the windows for condensation, that might work.

Be careful with the ventilation for the gas fire. Check carefully the manufacturers requirements and tally against the Bulding Regulations for peace of mind.

Window vents may not comply with your needs.For example trickle vents can be closed, hence are not accepted as gas fire ventilation. Also, a couple of trickle ventilators would not be an equivalent size to a 225mm square air brick as fitted in conjunction with many older gas fires.

PaulJM

Furts wrote: »

Be careful with the ventilation for the gas fire. Check carefully the manufacturers requirements and tally against the Bulding Regulations for peace of mind.

Window vents may not comply with your needs.For example trickle vents can be closed, hence are not accepted as gas fire ventilation. Also, a couple of trickle ventilators would not be an equivalent size to a 225mm square air brick as fitted in conjunction with many older gas fires.

That's exactly what worries me to be honest.

It's an oldish gas fire, and is checked every year, but it'sa powerful thing, and if the vents are designed to vent the room because of the fire, the window vents will not do that job
I can obviously keep an eye on the carbon monoxide alarms, but that seems the wrong approach.


What is the answer though? Ironically I'll hardly ever need the fire with no wind rushing through!

Furts

PaulJM wrote: »

That's exactly what worries me to be honest.

It's an oldish gas fire, and is checked every year, but it'sa powerful thing, and if the vents are designed to vent the room because of the fire, the window vents will not do that job
I can obviously keep an eye on the carbon monoxide alarms, but that seems the wrong approach.


What is the answer though? Ironically I'll hardly ever need the fire with no wind rushing through!

HiPaulJM

The legal answer is the Building Regulations require a 225x225 air brick to be kept unobstructed, if this was the requirement for your gas fire.

For example, I did have a 7kW input gas fire in a grate with the flue going up a chimney. This required a 225x225 air brick.

You could fix a sliding grille over the airbrick on the inside face of the room. MAP products do cheap ones in plastic, and probably still in aluminium. These are available at B&Q etc.

You would keep this closed, then slide it open when the fire is used. This is not a legal solution because at some stage someone will forget to open it before using the fire. Hence the risk of carbon monoxide poisoning.

In reality I kept mine closed, with a plugged in CO detector and never had an alarm go off. However, my house was not as air tight as a modern home, and, I suspect the combustion air was being drawn down the chimney.(In particular when the fire was set to low settings).

Hope this (potentially illegal) reply helps.