This is traced back to building codes and structural design standards.
How far apart to space trusses for metal roof.
Correctly measure the spacing of furring strips for a metal roof to further decrease condensation.
Putting the trusses into place.
Truss spacing for metal roof.
To determine how far apart to set rafters measure the width of the metal panel and then the width of the first hill and valley of the panel.
Roof trusses were usually produced on site in the past.
These standards are as follows.
Most are spaced between 18 26 inches apart.
So the space between rafters can be greater without reducing the maximum span.
With this design change roof trusses could be placed 12 feet apart making it possible for roofs to support the loads to which they would be subjected.
It all comes down to engineering.
If purlins are laying flat on top of the truss 5 or 6 feet is the max on 2x4 s edge up can go to 12 feet or more.
In the valleys due to the angle typically produced at the valley and the use of transition flashing it is essential that the.
It was perkins who pioneered roof purlins being placed on edge.
I ve had roof truss manufacturers try to convince me it is impossible to place wood trusses at spacings of over every 4 feet.
The trusses should be a little longer than the exact width to allow for overhang and you will need sufficient trusses to mount across the length.
Typically pole barn style buildings in my area have bays distance between trusses of 5 feet to 12 depending on pitch insulation and height.
With traditional stick frame construction the trusses are usually spaced 2 feet apart.
Engineers have since determined however that the physical design of a post frame building will allow for standard spacing as great as 12 feet from the center when using high quality metal connector plates and lumber.
Typical roof truss spacing means that they are usually about 24 inches from centre which means at the centre of one truss there will be a two foot gap or twenty four inch gap until the centre of the next truss.
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.
Twenty four inches is a common spacing of furring strips for a metal roof.
Tips on installing purlins for your metal roofing project.
Once you ve calculated the number of trusses you will need you should purchase the lumber.
The same concept holds true for roof trusses.
A metal roof must also allow for some overlap on each side of the panels which will reduce the effective width of the panel.