See pics. Trusses have what looks like 1x4s or 1x6s running between them, about halfway up the member. These run on both sides of the truss. The trusses also have pieces of what look like cut down OSB between them, on the left side of the attic (some of these are broken). I'm thinking the OSB bits were put in as they installed the trusses just to keep them all in place temporarily. What is the purpose of the 1x?
Attic Framing Question
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Just guessing, but I suspect both were just used to stabilize and position the trusses during installation. As the sheathing goes on the carpenters need to crawl all over those trusses and it is nice if they stay in place. Once the sheathing is on those extra boards could probably be removed.
Pros will be along, I've only installed a few loads of trusses.
Bud
Pros will be along, I've only installed a few loads of trusses.
Bud
Hi Neal, I've never seen the 1x4 on the truss engineering drawings. Again, limited experience but the ones I have stood up I used either approach, single pieces or had some longer boards marked at 24" oc. I have seen diagonal braces recommended but horizontal adds no strength.
Bud
Bud
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For wind and snow loading they call for T bracing on some members in the truss. so an extra 2x4 is nailed to the member in a T or L configuration.
When you have a few or a bunch the same you can do an L shape on the first and last and join them all with a 1x4 or 2x4. If they are all the same you would go from gable to gable. We often put close to 500 ft of 2x4 in a roof system after all the stuff you mentioned.
https://www.google.ca/search?q=T+br...XcFTQIHY8TCVIQ_AUoAXoECA8QAw&biw=1093&bih=502
They brace the truss members against buckling in compression, increasing their axial capacity. Whether the increase in axial capacity is required for the trusses to achieve their design capacity, probably cannot be stated with certainty without an analysis of the truss or a review of the design or the structural drawings. Perhaps the truss manufacturer or the contractor who installed them would know. That said, if they're all braced that way, it could be part of the design, but if only some of them are, probably not.
I assume the 1x provide lateral bracing against buckling by tying all of the attached members together?
I assume the shorter struts aren't tied together because they're shorter and the longer ones would buckle before the shorter ones do?
Would it be safe to say I could remove any of the OSB straps?
I assume the shorter struts aren't tied together because they're shorter and the longer ones would buckle before the shorter ones do?
Would it be safe to say I could remove any of the OSB straps?
Since trusses can be designed to many standards it is impossible to answer your question. To help, here is a good link that discusses bracing.
https://www.minera-rooftrusses.com/news/15/roof-bracing
Bud
https://www.minera-rooftrusses.com/news/15/roof-bracing
Bud
That wouldn't necessarily matter, as long as together they formed a continuous load path. That said however, the OSB pieces, in particular, appear to be scabbed on without alot of thought or care, so it's likely those at least were meant to be temporary. The longer 1x4s along the other line could be part of the structural system. Tough to say either for sure, though, without a review of the structural plans to see what was called for in the design.
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