We have a small storage room upstairs that used to have a tumble dryer and has an air duct taking hot air outside.
The storage room has been repurposed to store clothes/etc and we do not need the air vent/hole.
Whilst I don't necessarily want to block the hole, in case we ever need it in the future, I want to find a way so that cold air doesn't come in the house because it creates a mouldy patch in the corner of that room near the hole.
This is what it looks like:
https://imgur.com/a/kfwEMpO
Is there some plastic accessory that I could buy to cover the whole, or is there something you recommend me putting there to cover the whole?
It doesn't need to look pretty or anything.