Adding new air vent

[str]

I want to add a new air vent into my underfloor void to increase airflow.

I have a decent solum under a suspended timber floor (house circa 1900) and think I need some additional air flow under one side of the house.

Solid stone walls and I am confident in creating the opening but unsure how to secure the vent in the opening?

I will use a metal grill type vent. Do they get cemented in or screwed?

 

[noseall]

Air 'bricks' are sold in brick shaped sizes (obviously) and are mortared in place of a regular brick. Typical sizes are 9"x 6" or 9"x 3". You can either buy plastic or terracotta or even yellow clay.

There is no reason why you can't drill or disc out a neat enough hole in the stone for an air brick to be mortared in. However, depending how thick the walls are, means you may find getting through the the furthest or innermost part of the wall a bit tricky, but not impossible.

Be sure not to create a hole directly under a floor joist.