Last Fall I framed an 8 feet wide picture window opening in a two story plus roof bearing wall, successfully following advice given in FHB 137, p. 69, Framing an Opening in a Bearing Wall. The floor joists in that case also ran perpendicular to the bearing wall, allowing temporary bracing to span 8 or 9 joists using 3 screw jacks. Now, this Spring, with that great practice in mind, I’ve got an opportunity to build a walk-out basement bay and patio addition, which requires replacing bearing wall studs with an eleven feet span of microlam header. However, in this case, the floor joists run parallel to the two story plus roof bearing wall. Unless I’m totally wrong, I see no possibility of using these floor joists (midspan and parallel) to help relieve the wall load. What’s my alternative? Any ideas? By the way, I was amazed last Fall to see really how little weight was applied to my temp bracing and screw jacks. It seems that the upper floor wall waferboard sheathing (and perhaps drywall), and roof sheathing, must have helped to spread the load.
Also, with this bay and patio addition, the plan calls for a five feet wide French patio door and a five feet wide pentagon peak transom in the 2×6 gable above. Is there a way to support the five feet long ridge of the roof without a post where the transom would be? I’ve thought of making a pentagonal 2×6 header sandwich out of continuous 3/4″ plywood, or maybe a steel flitch plate. I’ve seen these open gables around, but have taken them for granted. How are they made?
Replies
Hard to say without a picture but it sounds like this is a gable end wall. Because it is an exterior wall, it is technically a bearing wall but if nothing actualy bears on it you've got it easy. Is the roof framed with trusses or a structural ridge? The ridge might have a point load coming down through you intended window space.
for something like this I might bolt an exterior header to the wall above, depending on siding type. Then I can get twobys with strongbacks jacking up under it at about fifteen degrees angle so there is room to work below.
I'd like to help, but I'm lost, not sure what the situation looks like.Mad Dog
I agree with Piffin. Without a picture it is risky to assume anything, but a gable end with the joists running parallel makes a non-bearing load wall likely. The ridge can be supported on the gable end by the rafters alone as long as there is a connection at the bottom chord (or where a bottom chord would be). If you can't figure this out, please get someone who can.