To us the code has always been nothing but the minimum standard. It costs very little time, and very little money, to install them. We use 2" x 8" ties on every rafter pair, well nailed, and bolted. If care is taken, and collar ties are really done right, they can provide resistance to spread, resistance to uplift, support for bending moment, and can help distribute an asymmetrical snow load (a very common problem here). Uplift is always a potential threat, has been well documented as the cause of many structural failures, and should always be taken into consideration in any design. Also, we get a LOT of breakage that does not result in catastrophic failure, just some number of broken rafters. Most from spread, but some from breakage due to bending moment. During periods when we get high snow loads, there are always a few catastrophic roof failures around the area. Yes, there are other ways to resist uplift at the ridge, but the collar tie has been and remains effective and simple (unless you're building a cathedral with a sharp peak). I responded to the structural benefit of collar ties in the one area most often overlooked: uplift. This thread began with a question about the structural need for collar ties and you turned it into a question of code. I've engineered everything I've built or renovated and my work has always been accepted by code officials and licensed engineers without alteration, even though much of my work has been non-conventional (shallow, frost-protected or rubble trench foundations, various double-wall superinsulated envelopes with no solid firestopping, indoor site-built composting toilets in lieu of flush, wood-heated homes with no central heat, passive fresh air systems with no high-tech ventilators, etc). I don't need a teacher - I am a teacher of design and building (though I'm always willing to learn from others). But I do have a problem with anyone assuming they're in the privileged position of judging the "correctness" of everyone else's anwsers. I have no problem with someone pointing out that my (quickly located) sources are not what I thought they were or don't directly address the issue at hand. I don't know.Ĭan we just agree that collar ties do very little and that there are better ways of providing whatever benefits they might offer?Ĭlick to expand.Thank you for responding in a more civil tone, but do you have any idea how patronizing it is for you (whoever you are) to "grade" me on my research or my posts? Why would I care? Why would I think anyone else would care. It is in no way related to the Texas State Building Code which is now the 2003 IRC. I know it shouldn't matter who misleads who on these forums but it gets under my skin.įor instance, the Texas Insurance Code is from the 80's and contains voluntary standards for those who wish to buy insurance on the Texas coast. When someone gets an idea he can't support and twists other information to support it, I find it irritating. I got on your case only because you were so adamant about the UBC and other codes. Of course, I don't have the latest revisions and the ICC might add them although it is unlikely since they didn't for the 30 years they were CABO. However, as I originally pointed out, my copies of the UBC, SBC, CABO, IBC and IRC do not require collar ties. revisions to the IRC doesn't include collar ties but who knows, they might get included. So, I was wrong and you were right - until July the Massachusetts code requires collar ties 48” o.c. It will now become law in July which I should have known. The Massachusetts Building Code was revised to add collar ties 20 years after it was first written but only to be deleted by the new IRC which, after a year postponement, was supposed to become law Jan 1st. Well done Riversong you’ve done some good research, even better than mine.
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