Roof Supports For A Pitched Roof

A roof is part of the building envelope.

Roof supports for a pitched roof.

A roof is the top covering of a building including all materials and constructions necessary to support it on the walls of the building or on uprights providing protection against rain snow sunlight extremes of temperature and wind. Modern pitched roofs may be supported with trusses which are hidden behind the ceiling creating a flat ceiling inside a home with a pitched roof. Gable walls need to be strapped to the roof at the maximum 2m centres using 30 x 5m galvanised mild steel straps. A low pitched roof would be 2 12 and it means that over the space of 12 inches the roof only rises two inches.

The other is just used to support the trusses. Each strap should be fixed as shown in the diagram opposite with noggins between the rafters to support the metal strap along its whole length. While most home builders will outsource the construction of roofing trusses the rafter supports of the roof itself learning to frame a roof yourself is one of the true arts of carpentry and a basic primer is covered below. The picture below shows the pitch of a 7 12 roof slope meaning that for 12 of horizontal measurement roof run the vertical measurement roof rise is 7.

Hip and valley rafters are cut and fixed. A pitched roof construction is the classic old school way of roof construction. A great deal depends on the pitch of the roof. Using trusses can add to the security of the roof and tends to be cheaper than utilizing the heavy duty beams needed for a pitched roof which will be open underneath.

Under purlins are cut and installed. Effective strapping at gable wall. Bevels and lengths for under purlins are determined. The pitch of a roof is the rise the vertical angle of the roof over the run the horizontal measurement.

Bevels and lengths for hip and valley rafters are determined from pitch of roof. With rafters collars ties struts ridges underpurlins ceiling joists hanging beams combination hanging and strutting beams pitching plates and so on. Pitch ratios range from 2 12 to 12 12. Creeper rafters are cut and fixed from pattern rafter allowing for overhang.

This is where a high pitched roof is necessary. Once again a 2 by 4 inch piece of lumber is placed between the trusses and parallel to the ceiling joists. This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement. The characteristics of a roof are dependent upon the purpose of the building that it covers the available roofing.