Joist to Sheathing Connection - Seismic Upgrade
Joist to Sheathing Connection - Seismic Upgrade
(OP)
I'm working through doing "voluntary" seismic upgrades on a local school. The architect is mostly replacing windows and a few other "aesthetic" things. In the process, the district has asked to do some seismic upgrades because there isn't a lateral system to speak of. Attached is a pdf of a section I'm working with. Does anyone have any good ideas on how to connect the roof joist to the roof sheathing? I'm assuming that the nailing to the roof joist isn't adequate...the district is missing some drawings that show some of the detail information on the original building.
Thanks
Thanks






RE: Joist to Sheathing Connection - Seismic Upgrade
I really see no easy and good solution to attach the roof diaphragm to the rim joist if the nailing is insufficient.
Mike McCann, PE, SE (WA)
RE: Joist to Sheathing Connection - Seismic Upgrade
I'm not entirely sure if the joist is intended to be a rim or not...and I don't want to go down the "ASSumption" route too terribly bad.
RE: Joist to Sheathing Connection - Seismic Upgrade
RE: Joist to Sheathing Connection - Seismic Upgrade
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: Joist to Sheathing Connection - Seismic Upgrade
That is where I'm stuck, I don't know of a fastener that is small enough and provides the capacity. It's not much, 220plf, but i don't know anything, and I don't think glue is really a good idea...maybe it is though???
RE: Joist to Sheathing Connection - Seismic Upgrade
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: Joist to Sheathing Connection - Seismic Upgrade
Alternatively, they can of course, remove the roofing and renail the diaphragm, or, they can install a new diaphragm by upnailing sheathing to the underside of the rafters.
RE: Joist to Sheathing Connection - Seismic Upgrade
Mike McCann, PE, SE (WA)
RE: Joist to Sheathing Connection - Seismic Upgrade
RE: Joist to Sheathing Connection - Seismic Upgrade
I have went with msquared's recommendation on the gluing, and now that I know it is T&G sheathing, I'm placing a new "Flat" block on the underside of the T&G with 2" Simp. SDS screws from the blocking to the sheathing...see attached. I think this will work pretty well. It's a lot of work, but I don't see any other option short of taking the roof off, and they have no interest in doing that.
RE: Joist to Sheathing Connection - Seismic Upgrade
RE: Joist to Sheathing Connection - Seismic Upgrade
RE: Joist to Sheathing Connection - Seismic Upgrade
Mike McCann, PE, SE (WA)
RE: Joist to Sheathing Connection - Seismic Upgrade
RE: Joist to Sheathing Connection - Seismic Upgrade
I think I have a good path forward for this now. Thank you all for the advice.