Air brick vents talk to me.

Bounce · 20 Dec 2025 at 19:57

Got afew of these across the house, bedroom, kitchen , upstairs bathroom.

House is built 1940’s there’s a significant amount of cool/cold air blowing into these rooms. Just wondering if anyone has similar and ever blocked them ?

Teknobry · 20 Dec 2025 at 20:54

Bounce said:
Got afew of these across the house, bedroom, kitchen , upstairs bathroom.

House is built 1940’s there’s a significant amount of cool/cold air blowing into these rooms. Just wondering if anyone has similar and ever blocked them ?

Older houses need to breathe. You can block them but you'll create issues with damp/condensation. Heat exchange ventilation would be ideal.

Brun · 20 Dec 2025 at 22:36

You should get a parapsychologist to have a look at them.

Hagar · 20 Dec 2025 at 23:54

They generally have at least half a cubic foot of spiders nest behind with the mother of all spiders laying hundreds of eggs. Other than that not really anything to be concerned about.

danlightbulb · 21 Dec 2025 at 10:29

Air vents were also often needed for open chimney's/ coal fires, and also things like gas cookers and non-room sealed boilers.

With modern boilers, electric cookers and if you don't use open chimney's you probably block off most of them.

It's still good to open windows regularly to air the room.

ben90 · 21 Dec 2025 at 12:12

IF the vent is under DPC level, don't block them without introducing some other way to supply fresh air in to the relevant areas. I have seen air vent covers or cowls which might be of use but I don't know if they work well or are too obstructive

If the vent is just in the middle of the wall, then possibly but people have mixed opinions on that.

Beans on toast Dave · 21 Dec 2025 at 12:13

"Air brick vents talk to me."

whats do they say?

Kelt · 21 Dec 2025 at 12:21

Beans on toast Dave said:
"Air brick vents talk to me."

whats do they say?

Whoosh, probably.

DB_SamX · 30 Dec 2025 at 20:08

Don't block them without professional advice. You most likely need them to ventilate below your suspended ground floor to prevent damp and mould, perhaps even to prevent the build up of ground glasses depending on location in the country.

happy_2008 · 30 Dec 2025 at 23:27

Don't block them but if you ever have pest issues then cover them with wire mesh.

Kohaashi · 2 Jan 2026 at 18:00

We have a 1930s semi with no cavity. We have kept the ones that vent underfloor (ground level and 1st floor) but blocked up the ones that are upper wall.

We have new windows with trickle vents and are in the process of insulating the external walls inside the house.

fastwunz · 4 Jan 2026 at 10:43

Do not block them - they are vital to ensure a cross flow of air beneath the suspended floor to keep it dry and prevent damp.