I'm going to add a egress window to a room in the basement so that it
can be used as a means of escape in the event of fire. Since this is a
retrofit, I will need to cut the foundation for the 48x48 window. Code
requires the window be not more than 44" from the floor.
If I cut all the way up to the rim joist, I will need to put an I-beam
across the span to support the joists. What does code require on the
size of the beam that would span 48-56"? If I don't have to cut all
the way up to the rim joist, how much foundation above the window must
remain before I will need to reinforce the span?
Thanks for your help.
1: I think the window that you are contemplating is bigger
than you strictly need. A 31.5" wide rough opening
should be more than adequate.
On the other hand, if you're going that far, it's not
all that much of a leap to just cut all the way down
to the floor, and put in a door and a stairwell.
2: You probably don't need an I-beam.
You should only need an I-beam if there's something
significant, like a post, coming down on that section
of wall. If there's any sign of extra blocking in
there already, then it's time to panic, and call a
Otherwise, if the wall in question is parallel to the
existing joists, just sister two treated joists to
the existing rim-board.
If the wall is perpendicular to the joists, pick
a different wall, or take enough headroom to
put lintel across under the rim-joist.
(Or: Prop up the joists-to-be-undermined with
a timberjack and a 4x4. Cut 32" off the ends
to give yourself room to work, sister that
section of rim-joist as before, and then
sister the cut-off joists on both sides,
attaching them to the new triple-header
with 4.5" hangers.)
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.