Roof Truss Spacing For Metal Roofing

It all comes down to engineering.

Roof truss spacing for metal roofing.

Kiln dried softwood is recommended for purlins or decking pine fir hemlock and spruce. Pullout values decrease if the fasteners protrude completely through the purlins. Be sure the larger edge is laid so that the small edge of the next panel will overlap it. Metal roofs and pole buildings.

Align the first metal roofing panel so that it overlaps the edging by 1 2 to 3 4 of an inch and is square to the roof. These standards are as follows. 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. Most are spaced between 18 26 inches apart.

Wider panels allow for greater spacing between rafters. Truss spacing for metal roof. When using purlins fabral recommends a maximum spacing of 24 on center note that 5v requires solid decking. Although the standard spacing of roof trusses may be the same as that of rafters with 24 inch spacing being a common option the design of a truss may allow for the use of a lower grade of lumber than would be required for rafters with comparable spacing and span.

Putting the trusses into place. A metal roof must also allow for some overlap on each side of the panels which will reduce the effective width of the panel. Rafter spacing is based on the width of the metal roofing panels. As most building these days are using those pre made trusses on the roof 24 inches become the main size for any roofing construction when it comes to its truss installation.

Install the roofing screws vertically along each rib in the panel. Place the first screw. 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. This is most likely the standard size that you will find on pre made roof trusses.

Typically pole barn style buildings in my area have bays distance between trusses of 5 feet to 12 depending on pitch insulation and height. I ve had roof truss manufacturers try to convince me it is impossible to place wood trusses at spacings of over every 4 feet. Depending on the complexity of your free computational tool it may require you to enter details about rafter spacing usually 16 on center bridge type height and board size. Their defense is our engineers will not allow us to.

Once you ve calculated the number of trusses you will need you should purchase the lumber.