When placing rafters for a tin roof also frequently referred to as corrugated metal or steel it is common to set the distance between rafters based on the size of the roofing panels.
Steel roof joist spacing.
Steel joists joist girders.
The same concept holds true for roof trusses.
When using purlins fabral recommends a maximum spacing of 24 on center note that 5v requires solid decking.
If the roof is not completely square you can decrease the space between joists but never increase the space.
Measure from the ends.
Open web steel joists are an engineered truss like construction component used to support loads over short and long spans alike.
Typically used in non residential construction steel joists and joist girders provide an economical system for supporting floors and roofs.
Since 1 nominal lumber and solid decking are thinner they provide somewhat lower pullout values.
This allows the panels to be securely attached to the rafters for maximum stability.
Pullout values decrease if the fasteners protrude completely through the purlins.
Live load psf dead load psf span calculator for wood joists and rafters available for the iphone.
Span calculator for wood joists and rafters also available for the.
An essential part of planning a patio roof or gazebo project is determining the number size and spacing of rafters beams and posts according to the loads they will carry.
Especially when steel roof truss spacing is concerned some engineers would argue that it is possible to only have a roof truss spacing of four feet off center even eight feet has been suggested.
A roof joist is always spaced no more than 16 inches apart from another roof joist.
Spacing in exterior exposure.
Common spacing for trusses on this type of building is often between 2 and 4 feet but trusses built with advanced designs may allow spacing as great as 8 or 12 feet.
Pole barn roof truss spacing generally tens to operate according to similar spacing principles though there are some proponents of having higher pole barn roof truss spacing.
Typically pole barn style buildings in my area have bays distance between trusses of 5 feet to 12 depending on pitch insulation and height.
In other words you would space a roof joist 15 inches apart from another roof joist but never 17 inches apart.