I'm building a 40x50 shop with a 2/12 pitch roof . How do I figure the cuts for the roof truses on I beam

Why would you be cutting a truss? They are engineered and assembled as a pre stressed unit. Hope you aren't up North! 2 1/2 pitch on a 40' span is a waiting disaster with a heavy snow load. Normally the truss sits flat on the top plate and is tied with hurricane ties. I have probably built 25 Habitat tor Humanity homes, all truss roof and never cut one truss.

Why would you be cutting a truss? They are engineered and assembled as a pre stressed unit. Hope you aren't up North! 2 1/2 pitch on a 40' span is a waiting disaster with a heavy snow load. Normally the truss sits flat on the top plate and is tied with hurricane ties. I have probably built 25 Habitat tor Humanity homes, all truss roof and never cut one truss.

As I mentioned in my question it is a shop with I beam that is not pre cut just pre enginered to free span 40' with a 2/12 pitch it is in south Texas so the pitch is not the problem it's the seat cut on the I beam that I was trying to figure out I have also built some habitat homes around here wonderful group was proud to build them and many thanks to you for your help with the habitat homes

So there is no truss? I'm a bit confused on the pitch. This is a truss beam, not a standard W truss? If this is a flat 2×4 you will have a hard time cutting a seat
Might be easier to make one wall higher like a shed roof. Or am I just way off base?

So there is no truss? I'm a bit confused on the pitch. This is a truss beam, not a standard W truss? If this is a flat 2×4 you will have a hard time cutting a seat
Might be easier to make one wall higher like a shed roof. Or am I just way off base?

That is correct there is only steel I beam and perlin and to keep the cost down we bought it in long runs that we have to cut and weld together so in the 40' span we have to cut the I beam on an angle to make the 2/12 pitch with the I beam also the three main uprights have to be cut on an angle to match the roof I was reading a similar post and it mentioned using the book I always use when buying a speed square so off to Lowe's I go in the a.m to buy another speed square this time I will keep up with the book thank you for helping out

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