Truss applicability limits

[Sifu]

2018 IRC. Do the applicability limits in this section apply if any one of the conditions is present, or only if all of them are present? I never quite know for sure. Some codes say something to the effect of all conditions being met. Some don't. I usually treat the commas as "ands", but English has never been my strong suit.​

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R802.10.2.1​

The provisions of this section shall control the design of truss roof framing where snow controls for buildings that are not greater than 60 feet (18 288 mm) in length perpendicular to the joist, rafter or truss span, not greater than 36 feet (10 973 mm) in width parallel to the joist, rafter or truss span, not more than three stories above grade plane in height, and have roof slopes not smaller than 3:12 (25-percent slope) or greater than 12:12 (100-percent slope). Truss roof framing constructed in accordance with the provisions of this section shall be limited to sites subjected to a maximum design wind speed of 140 miles per hour (63 m/s), Exposure B or C, and a maximum ground snow load of 70 psf (3352 Pa). For consistent loading of all truss types, roof snow load is to be computed as: 0.7 pg.

 

[Yankee Chronicler]

The 2021 Commentary doesn't clarify, but I have always viewed that as being if any apply. In other words, the building length may be 50 feet (under 60') but the width is 40 feet ==> no good.

 

[e hilton]

I read it as “all”.

 

[steveray]

You have to be under all of the limits...

 

[Sifu]

No, commentaries don't help. In this case I have both distance limits exceeded, but it is under three stories and roof slope of 4:12. So 2 of 4 conditions are satisfied.

 

[steveray]

No, commentaries don't help. In this case I have both distance limits exceeded, but it is under three stories and roof slope of 4:12. So 2 of 4 conditions are satisfied.

No bueno....