Loading Tables for Roof
Loading Tables for Roof
(OP)
Loading Table for Roof (PSF)
Purlin Spacing 2' 3.5' 4'
Due to Stress 800 368 280
Due to L/360 1700 500 340
Due to L/240 1900 560 380
I need help on how to understand this loading tables.
Thanks
Purlin Spacing 2' 3.5' 4'
Due to Stress 800 368 280
Due to L/360 1700 500 340
Due to L/240 1900 560 380
I need help on how to understand this loading tables.
Thanks






RE: Loading Tables for Roof
RE: Loading Tables for Roof
RE: Loading Tables for Roof
Throw your reference away!
Mike McCann
MMC Engineering
RE: Loading Tables for Roof
This source came from roof supplier not from ASD table.
I think I just got what I need. So, these load numbers are capacity or maximum allowable psf the roof can carry at a given purlin spacing. Pls correct me if I'm wrong.
I also recheck the technical properties and I dont know why there is a sudden drop of values from 2' to 3.5' purlin spacing.
Anyway many thanks to all!
RE: Loading Tables for Roof
RE: Loading Tables for Roof
Your statement "these load numbers are capacity or maximum allowable psf the roof can carry at a given purlin spacing " makes even less sense if that is possible. So if the first made no sense and this makes less sense the, we have negative sense going on here.
"Pls correct me if I'm wrong." You are wrong.
The only thing making any sense here is "This source came from roof supplier not from ASD table." Some one is trying to sell you something. Don't buy it until you have an engineers review as a2mfk said.
RE: Loading Tables for Roof
RE: Loading Tables for Roof
https://drive.google.com/file/d/0B3Q1YJbHf0rVME9lW...
RE: Loading Tables for Roof
See below the posting window..... "Or upload your file to engineering.com" please try uploading there. I, for one, am unable to see you document at the location you provided.
RE: Loading Tables for Roof
Michael.
"Science adjusts its views based on what's observed. Faith is the denial of observation so that belief can be preserved." ~ Tim Minchin
RE: Loading Tables for Roof
http://files.engineering.com/getfile.aspx?folder=f...
RE: Loading Tables for Roof
RE: Loading Tables for Roof
from your post above "So, these load numbers are capacity or maximum allowable psf the roof can carry at a given purlin spacing."
i'd pretty much bet the bank that this is not allowable psf, particularly for light gauge steel members. But until you give fuller information, i don't think i can be of much more help.
Good Luck!!
RE: Loading Tables for Roof
is this metal deck?
RE: Loading Tables for Roof
Michael.
"Science adjusts its views based on what's observed. Faith is the denial of observation so that belief can be preserved." ~ Tim Minchin
RE: Loading Tables for Roof
This is a high rib metal roof. I will send more details next week.
Thanks
RE: Loading Tables for Roof
That looks like a load table for some kind of metal decking. That is, the metal deck can carry those loads, at the listed purlin spacings, without being over stressed, or without exceeding the listed deflections. That should all be explained someplace in the footnotes of those tables. But, the purlins and the rest of the roof structure must also be designed to carry those same loads, or a reduced loading in lbs./sq.ft., in which case the decking won’t be the controlling design element. If you don’t know where this table came from (what product and manufacturer) or how to read/interpret the table, maybe you shouldn’t be doing this kind of work. You could hurt someone. I don’t see the loads you first posted in what you’ve posted now. Why not attach more of the table so we can see what your actually looking at?
RE: Loading Tables for Roof
RE: Loading Tables for Roof
RE: Loading Tables for Roof
You don't have to calculate reactions of the deck on the purlins, design them for the same uniform load as the deck with the addition of allowances for self weight and MEP over the tributary width (the purlin spacing).
Michael.
"Science adjusts its views based on what's observed. Faith is the denial of observation so that belief can be preserved." ~ Tim Minchin
RE: Loading Tables for Roof