Exposing and cladding manufactured trusts
This has been discussed at Breaktime at least once before. And there’s been an article in FHB by Mike Guertin where he exposes some trussing for a skylight shaft (and then uses Bondo to cover up the nailing plates in the manufactured trusses).
I initially was of the camp that, besides all the hassles you might encounter, it would look too busy.
But then I saw one example of some exposed trusses in this kitchen remodel which makes me rethink that it could work. It is busy (w/ trusses 24″ oc) but seems to be OK. Beats a flat 8′ ceiling methinkinks.
I also thought it was interesting how (bubble) skylights spanning multiple trusses were used — you can see more about the construction in this website.
Thoughts?
Replies
You'll need some braces on the bottom chords of the trusses. They're in tension most of the time. But the forces reverse in high wind situations, which means you need some braces on the bottom chord.
Some of the webs may need braces too. Just depends on the truss and the situation.
Truss to vaulted ceiling
Boss. If the truss was originally designed/engineered as a simple king post truss, why would you need additional bracing? Granted, normal king post trusses would have a couple of diagonal braces. Maybe I'm missing something. Was some diagonal bracing removed from the origional trusses?
Sounds like you're talking about the webs that are built into the truss. I'm talking about braces that are perpendicular to the truss that keep the members from buckling when they're in compression.
Interesting points about bracing. Some of the during-construction photos show additional vertical members added between chords (for example those vertical members above the island were a different vintage of wood pre-cladding and very obviously added later). I thought those were done for some sort of aesthetic reasons.
But I don't see any LATERAL bracing that is exposed. Maybe the exposed span didn't need any bracing and the bracing effected at the soffits is enough? (I would expect bracing would need to be 4' or less on center though.)
Actually, maybe the vertical posts were original on further review after oops's post about king trusses. All the members look original. Seems like might be a Howe / tri-bearing truss? Not sure if that would follow the same guidance about no need for bracing as a king?
(Sorry for the large photo, but I linked directly to the original source to stitch it in here.)
View Image
Bottom chord
It's pretty clear from this photo that less than 1/2 the truss is exposed. The trusses are fully braced at the center of the truss which is inside the soffit over the cabinets. The top chord is enclosed at the new cathedral ceiling plane.
Not a lot of space for insulation...
If only the top chord depth is where the insulation goes, that's a depth of 3.5" ... seems pretty skimpy though that's what the photo suggests.
The spacing varies depending on the forces in the bottom chord. It's specified on a truss by truss basis.
Sine there was previously a ceiling attached to the bottom chords no additional bracing was needed. Since you opened things up it's a whole different ball game.