by Jerry Peck - Codeman on Tue Sep 21, 2010 8:22 pm
So, they are going to make you put in a 36" door anyway, or you are just doing it because you want to?
The size and strength of the header depends on what it is supporting, including the snow load (if there is a snow load).
The MA code that I have does mention joist hangers and what they have to meet, but that code also refers to a section which is not even in that code - which is puzzling to say the least.
Based on the fact that the MA codes does mention joist hangers, joist hangers should be allowed for your installation, however, attaching the joists hangers will be the problem as you will have a difficult time attaching them without removing the exterior siding and interior wall (drywall?) to access an area to nail the hangers to the existing framing. You would probably be better off finding an engineer who could work the numbers for you and use angle brackets install below the header for the vertical load of the header, then specify the toe-nailing required for torsional stability of the header, maybe even come up with a support-from-below bracket which also extends up vertically and provides that lateral and torsional support for the header.
Doing retrofits after-the-fact as you are requires some ingenuity and thinking about new possibilities and not just trying to do it with off-the-shelf material. Usually less expensive in the long run too.
Jerry Peck - CodeMan
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Construction Litigation Consultant - Retired
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