Steel Roof Joist Spacing

Maximum rafter spans for a patio roof.

Steel roof joist spacing.

Pullout values decrease if the fasteners protrude completely through the purlins. So the space between rafters can be greater without reducing the maximum span. If the roof is not completely square you can decrease the space between joists but never increase the space. 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.

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. 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. Span calculator for wood joists and rafters also available for the.

This allows the panels to be securely attached to the rafters for maximum stability. Open web steel joists are an engineered truss like construction component used to support loads over short and long spans alike. 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.

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. Since 1 nominal lumber and solid decking are thinner they provide somewhat lower pullout values. A roof joist is always spaced no more than 16 inches apart from another roof joist.

Steel joists joist girders. Truss spacing for metal roof it all comes down to engineering. Measure from the ends. 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.