"Peter Stockdale" wrote in message
news:ct6bvc$1s1

Obviously no mouse would be able to effect entry through airbrick size
holes

Well, I disgree ... they can.

Get some expanded aluminium and fix it round the air bricks. IF mice are
getting in through there it will stop them. It won't stop air circulation.

I've used it to prevent swarming bees from gaining access to cavity walls.

Mary