Can anybody give me a bit of advice on the type of air vents to use in ICF walls?

We are building an ICF house on a sloping site.  We have a walk-out basement with an ICF wall at the back and then a sloping void behind that wall with a suspended timber floor above.

Building regulations in the UK quite sensibly say that this void must be ventilated and the common way to do this is with rectangular air bricks that are the size of standard house bricks.

This is fine if you are building a brick house but my concern is that if I use this type of vent then I will get an air pocket under the air brick when we pour the wall.  The answer would seem to be to use a circular shaped vent.  Is that the normal solution?

Thanks

Andrew

You can build it with a buck like a window or a door and slip any acceptable vent in later. If you leave a space in the bottom panel of the buck, you can see if the concrete has filled beneath it.

If the location of the air brick isn't critical and if steel allows, you can wait until the forms are partially filled before you poke it down there onto the concrete surface and continue filling.

If the inspectors don't care, you could put the brick up on end which would almost certainly prevent an air pocket from forming underneath.

You could also stuff a foam filler block in there and dig it out later to mortar your air brick in.

Or, you could use a circular shaped vent.

Lots of clever ideas there! Thanks very much.

AA