Here is the formula for calculation of a roof purlin.
Long span c purlin roof design.
Three equi spaced supports equal spans.
Spantec has prepared these tables for use by people skilled in the design and specification of the.
These tables are for spans in which purlins are lapped over each support where the lap length is 15 of the span.
Data is given in each table for.
Two supports one at each end double span.
Purlins rails eaves beams z e d p u r l i n s y s t e m s e a v e s be a m s z e d c e e s h e e t i n g r a i l s fl o o r c e e s design guide september 2014.
Four or more equi spaced supports.
C purlins and c girts.
If a steel purlin must span 24 feet between girders it should be at least 12 deep for girders calculate 3 4 inch of depth for every foot of span.
Arrangement of purlins by default purlin sections assume the slope of the roof they are supporting.
For 2x4s purlins the posts are spaced in 4 feet distance.
The spacing of purlins usually call for careful arrangement in the sense that it should follow the nodal pattern of the supporting trusses.
This post will be focusing on design of steel purlin using cold formed sections.
Tables are given for 5 or more spans.
For outwards loads on equal continuous spans the bridging shown is required in the end spans.
Cpe 0 9 and cpi 0 2.
Posts these span tables are designed for a minimum post size of 50 x 50 x 2 5mm up to a maximum height of 3 0m.
Safe roof purlins spans.
Maximum roof slope is 5 for monoslope and 22 5 for pitched roof.
If you want to know how to support roof purlins they are usually supported by 2 4 or 2 6 struts or posts.
The standard of purlin length will vary anywhere between 100 to 300 mm while the thickness will vary anywhere between 1 to 3 mm.
We manufacture any component from 1 2 steel subgirts to 12 section up to 10 gauge.
The c sections can also form part of the columns and rafters in these smaller applications.
Flexospan provides standard even profile c purlins and c girts as well as custom profiles and punching patterns.
For purlins calculate 1 2 inch of depth for every foot of span.
Continuous purlin span are simply supported at each end and at a series of equally spaced intermediate supports.
The safe spans below are suitable for sheds and class 1 structures with the following assumptions.
Flat roof span tables allow for a maximum roof pitch of 5ยบ.
Max roof span allowed 12m.
High pressure zones kl 1 5 and 2 0 included.
The number of supports beams or purlins affects the allowable span length.
Use recommended minimum roof pitches as specified by roof sheet supplier.
Monoslope pitched single.
