On 22 Nov 2006 18:55:12 -0800, "smcjensen"
wrote:

I have space over a garage I'd like to convert to a 4th bedroom for an
upcoming child. The space is trussed and I was thinking of sistering
conventional framing beside all the trusses then cutting the obstrucing
portions of the trusses out. I don't want to tear down the entire
garage and throw away a perfectly good roof and siding and I don't want
to disrupt the neighborhood with a month's worth of torn up house. The
roof line is a simple A frame. I've built another addition on my house
after which the building inspector said I did a very good job so I'm
not a complete novice. The real question: is this idea crazy stupid
or has it been done before?


Just remember that the truss does two things, it holds the
roof deck up, and it keeps the walls that the roof rests on from
coming apart. As long as you replace BOTH those functions
(joists and rafters) you should be ok.

Is the garage door in the gable end, or one of the load bearing
walls? 'Cause if your new rafters rest on the wall with the
door in it, you'd best make sure that whatever beam goes across
there is sized to take half the floor.