> 1: Do current building codes call for a fire-resistant door between a
> garage and the living area? (The existing door dates from the 70's.)
The ones I'm familiar with do.
> 2: The doors I see at HD, etc. are all pre-hung. Do you think it
> would make more sense to discard the frame that comes with the door
> (or maybe order a non-hung version) and fix the door to the existing
> frame, or rip out the existing frame and use the new one? One
> downside of ripping out the old frame is that I would have to re-do
> the surrounding trim.
IIRC fire doors are approved as a unit with their frame and seal.
You're also required to have a self-closing hinge.
I'd certainly change the whole assembly, you'll spend a very long time
trying to true up a new door in that old frame even if you weren't
concerned about code (and my guess is your homeowners insurer would
prefer that you were.)
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