Cavity wall insulation team block up air bricks

spiritus

My mum has some cavity wall insulation installed some time ago and we have noticed that the old air bricks in the house have white "gunk" in them..it looks like dry silicone sealant ??


It looks like new air bricks are fitted as part of the process but I'm curious as to why they would block the old ones up.

sinizterguy

Could it just be a part of the process, where they cannot protect the old ones from being filled up ?

Just guessing and would like to know the facts.

richy999

I imagine that the installers could not guarantee that the old air bricks had the necessary sleeves between the inner and outer cavity air bricks so sealed them up to stop the insulation spilling out… which leads me to wonder if they sealed up the inner air bricks also.

Furts

spiritus wrote: »

My mum has some cavity wall insulation installed some time ago and we have noticed that the old air bricks in the house have white "gunk" in them..it looks like dry silicone sealant ??


It looks like new air bricks are fitted as part of the process but I'm curious as to why they would block the old ones up.

Alarm bells ring on hearing this. To put in proper air bricks, with a cavity liner and a grille on the inside is a significant amount of work. The brickwork needs cutting away, a cavity tray should be put above, the inner leaf needs careful opening up and possibly plaster patching. This does not come cheap, and would be outside the abilities of most cavity wall insulation teams. Hence I am concerned by what may have been done.

tony6403

richy999 wrote: »

I imagine that the installers could not guarantee that the old air bricks had the necessary sleeves between the inner and outer cavity air bricks so sealed them up to stop the insulation spilling out… which leads me to wonder if they sealed up the inner air bricks also.

I agree with the above theory .
Also , were some old air bricks ventilating a pantry or bedroom in which case I can understand why they simply filled them.
Are the new air bricks replacing old ones for under floor ventilation?