Roof Members And Their Dimensions

There are two basic methods of pitched roof construction.

Roof members and their dimensions.

They vary in size depending on their length and spacing. Their main purpose is to support the joists and allow for shorter joists to be installed. 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. The members making up the main body of the framework of all roofs are called rafters.

A purlin is a horizontal piece of timber or metal which supports the roof s rafters or decking and helps to prevent your roof from sagging. With the diagram above applying pythagoras theorem x 2 rafter length 4 5 2 3 5 2. For rafter check the height of roof and the breadth of plan to determine the rafter which is the falling portion of the roof except is already given from the section lets take the height of the roof as 3 5m and the breadth of plan plus overhang is 9m. Often you can get discounts for using certain types of metal or asphalt so always make sure that you check out these options when running all the numbers.

A roof is part of the building envelope. The characteristics of a roof are dependent upon the purpose of the building that it covers the available roofing. A cut roof this is the traditional method of cutting the timber on site and building up the roof using rafters ridge boards joists and purlins etc the exact details being determined by the size of roof size of timbers etc. Wire fences and other fences not over 6 feet 1 8 m in height.

Pitched roof construction. This is especially true with shingle roofs both metal and asphalt. A hip rafter extends from the wall plate to the ridge in the angle of a hip roof. Rafters are inclined members spaced from 16 to 48 inches apart.

The tops of the inclined. Platforms walks and driveways. For example a steel roof will typically cost less than an aluminum roof. They do for the roof what the joists do for the floor and what the studs do for the wall.

In roof area used as storage sheds playhouses and similar uses.