Rectangle Exhaust Vent

hijack

The floor joists in my basement are partially in the foundation so my rim joists are half concrete half wood.

I need to cut a 6" hole for an exhaust outlet for a HRV.

There is an existing 3.25 x 10. rectangle vent.

Can I just put a 3.25 x 10 x 6 angle boot and get the equivalent air flow?

brandonmcginnis

Basically, yes. It will boil down to manufacturer specs and the tempermant of your local inspector.