Adjusting Floor Joist for HVAC
 

Trying to convert garage into family room. I want to run ductwork from
basement to attached garage.

HVAC guy wants to put a vent under my front window. Problem is that
the end of the garage (where the vent will go), is about 4' past the
end of the basement. So if I took the ductwork out of the last
basement bay, it would be about 4', and a few garage bays, away from
the target vent location.

So I need the ductwork to come out of the basement wall, hang a left,
go "through" a joist or two, and enter another bay. Then it can run
down that bay and end in the vent.

So how should I adjust my floor framing to accomodate this duct? Is it
possible to end my joist 6" before the wall, and "box it out". Will
this have negative impacts on the strength of the floor?

Thanks,

Chris

Adjusting Floor Joist for HVAC
 

wrldruler wrote:
....

So how should I adjust my floor framing to accomodate this duct? Is it
possible to end my joist 6" before the wall, and "box it out". Will
this have negative impacts on the strength of the floor?

What is going to support the joist if it ends short of the wall?

It would at the bare minimum have to have a multiple-thickness header on
the adjacent joists for them to support it and, depending on the length,
perhaps a center support. But, there could be a way possibly. It's
possible if you use a substantial subfloor that the 6" span would be ok
but again it depends on the length. Two short joists would be a span of
48" which would probably be ok w/ 3/4 T&G, three would be 64" -- there I
start thinking "drum" even though it's narrow, that long a length w/
only side support is going to have some flex. More than that and I'd be
looking for some way for sure to get some support across there.

Although on the joists -- are they essentially just resting on the floor
since it's a garage? Or are they hung -- seems like maybe an earlier
thread said somethng about raising floor to conventional 8-ft ceiling
where is now 10-ft? If that were the case could not run duct
underneath, perhaps?

So many questions, so little information... :)

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