I also need to decide if we are going to remove a 10'8" beam that runs in line with one of the stairwell walls and put in a 14' replacement (had an engineer do all of the numbers for us). The beam rung about $170, but I am a little nervous about having to jack up the trusses about 1/8" in order to pull out the old beam where it rests on the concrete exterior wall, and then manhandle the new one in place just to open things up a couple of feet at the bottom of the stairs. Lots to think about.
I just did something similar. It wasn't too bad really. Just braced the trusses with 2x4's and hammered shims to raise it up. Sounds like your task is a little more difficult because of the exterior wall thou.
Before:
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Also, you're really making me jealous with all of you talk of sound proofing. I've tried to make minor decisions to help disconnect my basement HT from the upstairs but at best it's going to make so little difference I'm sure everyone upstairs will think they are sitting in the same room.
