The same concept holds true for roof trusses.
Roof strut spacing.
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.
Follow this guide to ensure the spacing and stability of your diy roof trusses.
So the space between rafters can be greater without reducing the maximum span.
Struts should be adequately supported over studs in timber walls.
Struts are generally more efficient the closer they are to the vertical.
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.
To determine how many trusses to create you will first need to measure both the width and the length of the structure you are building.
They should have anti slip blocks where necessary to prevent them sliding horizontally.
They are birdsmouthed or halved to fit underpurlins as shown below.