Field house roof deflection criteria
Field house roof deflection criteria
(OP)
I am used to using LL/360 & TL/240 for long span roof joists. I have a field house with a width of 70' and the price difference between LL/360 & LL/240 is enormous. The joist is going to have a significant pitch to it, so I am not worried about ponding effects. There is no ceiling; the roof deck is 1.5Bx22ga with tapered insulation.
My question to the more informed folks here is if I am conservative with LL/360 & TL/240?
Thanks and merry Christmas.
My question to the more informed folks here is if I am conservative with LL/360 & TL/240?
Thanks and merry Christmas.






RE: Field house roof deflection criteria
RE: Field house roof deflection criteria
I think you are within the guidelines of the IBC, but I wonder, as Hokie, why the tapered insulation... Are you attempting to channel the water laterally across the top of the joists to artificially created drainage channels rather than varying the height of the joists?
Mike McCann
MMC Engineering
http://mmcengineering.tripod.com
RE: Field house roof deflection criteria
RE: Field house roof deflection criteria
RE: Field house roof deflection criteria
RE: Field house roof deflection criteria
Mike McCann
MMC Engineering
http://mmcengineering.tripod.com
RE: Field house roof deflection criteria
By the way, this is less than the allowable deflection from IBC Table 1604.3. I assume that the open web joist people have a good reason for limiting the deflection beyond code. Maybe the roofs got too bouncy.
RE: Field house roof deflection criteria