are large vents absolutely necessary

[dandt]

hello I have an ex council semidetched house built in 1950 or 60. walls are brick with cavities and some of the outside walls have painted 'spar'. Anyway I understand the need for ventilation but am wondering if the vents need to be as large as they are (about 12inches by 9inches at a quick guess). In the bedrooms i have fitted the typeof covers that slide shut. However I feel like I'm losing a lot of heat. They have a wooden frame throughout wall fropm inside to outside. Could I brick and plaster in some of the area, and what size should I leave still?
thanks
derek

 

[ginger100]

the vent was put there for a reason, trust what you have and the reasons for it.

 

[jm2000]

Hi there is no reason for those vents to be coming into the room. i have been told why in that era they thought is was a good ideato vent the house, but for the life of me i cant remember.

We have an ex council estate near us and from time to time we do get a call go and close them of with insulstion and then seal them with 2 brick but only on the inner leaf (wall). but remember ro remove the wooden frame so that the cavity still has air flow.

Hope this helps

 

[dandt]

thanks jm2000
I've already sealed a bathroom one from inside. I have extractor fan fitted nearby in any case (and my wife always leaves the small window open!). The grill has fallen off outside. Before I reinstate the outside I assume I could just drill some holes in the wooden frame rather than trying to hack it out
Would this be ok
thanks
again

 

[big-all]

do not fill in any vents untill your fully satified that a gas appliance in adjacent rooms have there own vents

 

[freddiemercurystwin]

i have been told why in that era they thought is was a good ideato vent the house, but for the life of me i cant remember.

Think you'll find its to prevent condensation! Block up your vents and risk condensation occurring.

 

[Nige F]

i have been told why in that era they thought is was a good ideato vent the house, but for the life of me i cant remember.

Think you'll find its to prevent condensation! Block up your vents and risk condensation occurring.

They thought us council house kids were pongy .Places were bloody freezing with no roof insulation -Crittall metal frame single glazed windows- one coal fire to heat the hot water. Block them all up . BUT CHECK the gas fire/ boiler ones as suggested In fact get any gas appliances checked anyway . NO JOKES around gas safety.

 

[stuart45]

dandt,
You don't want to use it to ventilate the cavity. As it's got a liner it was intended to help stop condensation, or vent a open flued appliance as stated in the previous posts.
Using large air bricks at high and low levels was done years ago to vent the cavities in cavity walls, but was found to cause cold spots in the wall, and also research showed that they reduced the thermal eficiency of a cavity wall to less than a solid 9 inch wall.

 

[dandt]

to Stuart 45
thanks
sorry if I am being thick I am assuming you are advising me not to drill holes in the wood 'tunnel' but that i can go ahead and generally block them up.
By the way, I respect the concerns out there about gas, My boiler is nowhere near the bathroom and has its own vent; there are no gas issues near bathroom

 

[Nige F]

dandt,
and also research showed that they reduced the thermal eficiency of a cavity wall to less than a solid 9 inch wall.

that was high tech research probably had the eficiency of a 4 inch single brick wall

 

[StephenW]

After doing the Gas elimination checks, why not block it off temporarily by stuffing it up with insulation material and see if it causes any other effects. If not then you could do a more permanent job.

 

[dandt]

thanks stephenW
that's the best solution for now (as there seems to be mixed views)
thanks to everyone for contributing
hope I havent started any arguments

 

[stuart45]

to Stuart 45
thanks
sorry if I am being thick I am assuming you are advising me not to drill holes in the wood 'tunnel' but that i can go ahead and generally block them up.
By the way, I respect the concerns out there about gas, My boiler is nowhere near the bathroom and has its own vent; there are no gas issues near bathroom

I wasn't saying that it is definately OK to block up the vents, just that you don't want to use them to vent the cavity. However it may well be OK to block them, but a tempory block as advised would be better.
You could check with a hydrometer how it affects the R/H.