Possible alternative to ridge beam and rafter ties?

nocredentials2 · Nov 1, 2022

In reviewing options for bracing a wall against the outward thrust from roof members, I have yet to see a truss formed from the top of the wall stud, to the interior of the joist. It's like a purlin, but instead of supporting a long rafter span, it prevents the wall from bowing out.

I'm curious if you've ever seen this type of thing in the wild before, and if so, what is it called?

One potential problem I see is that while this may prevent the stud in the wall from moving, it might not help the double-top plate from bowing out.

XR250 · Nov 1, 2022

I design these pretty regularly. Best to have the brace run from the rafter to the floor joist and keep the left pony wall out of the load path. Works best with dimensional lumber - not so great with i-joists or floor trusses.

phamENG · Nov 1, 2022

Attic trusses use this principle indirectly.

I've tried to use them before, but they only seem to come up on houses that will use I-joist systems and, as XR pointed out, they don't work so well. They also don't work well with small rafter sizes as demand on the connections can get unwieldy if you want to keep things "normal" for unsophisticated framers.

BAretired · Nov 2, 2022

It could be fabricated as a truss, without using I-Joists. See Revised Attic Truss below. It isn't a true truss, but neither is the upper diagram. In either case, the "bottom chord" is acting more like a beam with point loads at D and E and floor live load between.

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Possible alternative to ridge beam and rafter ties?

nocredentials2

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