I'm installing a Zephyr AK6500 range hood. The kitchen is on the first floor a 2 story home, which was built in 1967. I've run 6 in. round ductwork in a joist bay in the kitchen ceiling to the exterior. I still need to cut the hole in the siding and install the wall cap.

The joist bay is perpendicular to the band joist.

My concern is that I will have to cut a 6 in. hole in the band joist to attach the wall cap. Is that size hole okay?

I can't reinforce the band joist from the interior as the cabinets are already up.

2 Answers 2


You have not mentioned the size of the joist. If it is 2 x 10 or larger I don't see a problem (heck, 2 x 8 might even be fine). The band joist (I call it the rim joist) is primarily for providing an attachment point for the floor joists and for holding the floor joists plumb and true. The load of the wall and structure above is distributed across the bottom plate and all the floor joists, so I do not think there is a structural concern here.

  • Buildings need to withstand more than gravity loads. Other forces include uplift (opposite of gravity loads), shear (parallel to the band joist), and pullout (longitudinal to the floor joists). Wind and seismic loads dominate structural design in many parts of the world.
    – user23752
    Aug 13, 2014 at 0:17

You could cut a large rectangular hole from the outside and then put a 90 degree turn in the vent pipe upwards before exiting the exterior. The void in the exterior surface would be filled with a piece of wood, like a light mounting block.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.