Cavity Draft Caused by Ventilation for Gas Fire - Also Patchy Insulation Information, help, tips and advice on cavity walls, ceilings and lofts etc....

[jaygee]

Hi,

We've just moved in to a mid 70s build house and wonder if anyone would have a suggestion or two about the following.

We noticed a breeze coming from a couple of electric sockets on an outside wall, the back of these sockets seem to be going in to the cavity. Now the house apparently has some cavity wall insulation so found this a bit surprising. I popped the cover off a nearby extremely breezy ventilation panel I had been meaning to look and found a large hole going directly outside and through the cavity, guessing this is the source of the socket breeze. I've had it suggested that it might have been because there's a gas fire installed in the room but out previous house had a gas fire and didn't have a great big hole in the wall.



On taking a picture or two in the cavity I can see some foam like insulation but it's in the distance and looks pretty degraded with nothing down low so I'm not surprised there's a breeze coming out of nearby sockets, the bits I've come across in the roof space are powdery.




Is a hole this size required for ventilation or can it be blocked? Even if so should it not be in a pipe or something?

Is this patchy insulation going to cause any problems going forward?

Thanks,

Jay

[jaygee]

The hole diameter is about 5 inches and on looking around I can see there are easy replacements for the external and internal vents for use with gas appliances in the room with the external being a cowl to reduce drafts and pipework to join the two through the cavity so this would be an option if it has to remain. I guess I need to speak to a gas installer about appliance ventilation requirements before having it fully plugged.

Still not too happy with the partial cavity wall insulation and the holes behind the plug sockets but not sure much can be done there without incurring a large expense.