Hole in wall

MissPeachtree

Have discovered a large 4 inch hole in our wall.  Was covered over with a vent and recently moved in so not noticed until now.  The hole goes from the inside all the way to the outside of the house, through the cavity wall.  Vents on both ends.  Inside the hole is a large round plastic tube which is hollow.  No idea what this hole was for but we would like to fill it in as it lets a fair bit of noise in.  Can anyone suggest the easiest way to do this?  Husband and I are fairly handy and would prefer to do this ourselves.

Grenage

It sounds like a standard vent, possibly installed to provide air for a stove or fire in the house.  Your best bet is trying to find matching bricks for the outside, and wherever for the inside.

Rodders53

Pictures in and out?

Might it be used for a tumble dryer vent? 
Or a portable aircon unit vent?
Is there an open fire / or fossil fuel burning stove in the same room that needs air?

Do not permanently block anything until you are sure it's not needed for combustion safety!! 

If the vent might be needed in future (e.g. aircon or vent for a fire) then re-fit vent covers after stuffing the void full of insulation to minimise noise and draughts.  Just remember to remove it before lighting that fire!

daveyjp

Sounds like a tumble dryer vent.  If you know it isn't needed and it will never be needed again fill it with expandable foam.

grumpy_codger

If you just want to stop the air flow, you can just remove the vents (grid?), fill the holes with expanding foam and then fit the vents back.
Or, if it's 110mm pipe, you can buy some plastic blanking cap to close the pipe outside, e.g. https://www.accu.co.uk/round-ribbed-inserts/585235-HRRIE-110-6-28-2-4-5-LDPE-W

twopenny

Depends on age of house because I lived most of my life in a 1920s house and it had a through wall vent as standard in the bedroom on the outside wall.

I only blocked it back in the 90s leaving the outside in place and board inside plastered over flush and painted. I didn't get noise or wind affecting the room.