huangyhg

preliminary spacing for roof purlins and wall gerts
hello all,
i have been given the responsibility of selecting a cladding system for a 15x21m, 12 m high industrial building. however, before selecting the size of the panels, i have to find out what a reasonable spacing is for the c shaped wall gerts and roof purlins, which will be supporting those panels. i was told that tables exist somewhere which can give me a very reasonable spacing, depending on only a few parameters. where can i find these tables?
much thanks.
clansman

what country are you in?
canada.
find the names of the manufacturers of the types of cladding your are considering using. visit their website or call them and request information on the sizes they make and spacing they typically use. also get cost information if you can along with servicability data. also, look around at other projects in your area and see what others have done and at how well they appear to be holding up. your local building department may give you this (public)information too, if you ask politely .
good luck
clansman,
as i work in australia, am not familiar with the cladding types you use in canada. but we use a lot of different cladding profiles in australia, supported by both zed and cee cold rolled purlins and girts. in general, the first decision to make is the type cladding you will use. then, you space the supports to suit the cladding spans. cladding can span anywhere from 600 to 3000, dependent on the type, depth, and gauge of material. also on your loading conditions. our cladding spans are normally controlled by wind, but you may be controlled by snow on the roof.
once you determine the cladding and support spacings, which may be different for walls and roof, you proceed to design the purlins and girts. we have tables provided by the manufacturers which are based on our light gauge metal code, and i imagine you have similar tables available.
sounds as if your supervisor should do a better job of pointing you in the right direction.
clansman has said the same thing i would have.
i would add that in australia we would generally limit purlin spacings to 1500mm maximum because of workplace health and safety issues. over 1500 requires some onerous conditions on safety mesh.
good point, sdz.
much thanks everyone! that was very helpful.
this is actually my very first task in my very first job.
clansman,
you are not expected to know everything so ask. most senior engineers are happy to answer any amount of questions once, so ask away, take notes as long as you dont ask the same question twice.
if i was your senior engineer i would be worried if i didnt recieve a lot of questions from you.
if you dont want to look like you dont know something then just say ' i want to check my understanding of this...' or something similar.
as for the task at hand, check that the architect hasnt already specified a roof sheeting, if so then this will dictate your purlin spacing.
regards
csd
thank you for the kind advice, csd72!
the architect has only specified the minimum base material thickness and other minor details.
following hokie66's advice, i checked a website of a cladding manufacturer and found load tables. i think from here i can manage.
thanks again everyone!!

__________________
借用达朗贝尔的名言：前进吧，你会得到信心!
[url="http://www.dimcax.com"]几何尺寸与公差标准[/url]