Roof Members With Dimensions

The truss is a framework consisting of rafters posts and struts which supports your roof.

Roof members with dimensions.

In the united states a run of 12 inches 1 foot is used and pitch is measured as the rise of the roof over 12 inches. A waterproofing layer that protects the roof valleys from leaking. For example a steel roof will typically cost less than an aluminum roof. The important point to keep in mind when you use your truss calculator is that every truss calculation is completely unique and is based on the size of your roof and its specific dimensions.

The move to set national standards for lumber in the united states began with publication of the american lumber standard in 1924 which set specifications for lumber dimensions grade and moisture content. Rafters are inclined members spaced from 16 to 48 inches apart. It also developed inspection and accreditation programs. One of a series of diagonal members of the truss that meet at the apex in order to support the roof deck and its loads.

Steel z purlins and z girts are also available with other depths and flange widths. Calculation of roof members. A waterproofing seal installed along the roof s valley line with taktekkernbergen no. The vertical rise of the top chord per 12 horizontal inches is the roof pitch or slope.

We manufacture any component from 1 2 steel subgirts to 12 section up to 10 gauge. They vary in size depending on their length and spacing. In the uk a concrete tiled roof would normally have rafters at 600 mm 24 in centers roof battens at 300 mm 12 in centers and ceiling joists at 400 mm 16 in centers. Dimensions matter as do the total amount of feet.

The tops of the inclined. If the overhang extends beyond 24 inches say to 30 inches then a 2 6 top chord for the tail section will be required to handle the additional overhang. The united states still uses imperial units of measurement and framing members are typically spaced sixteen or twenty four inches apart. These dimensions are essential to determine the accurate span of rafter overhang underpurlins fan struts etc.

For example 4 12 pitch means 4 inches of rise in 12 inches of run. This is especially true with shingle roofs both metal and asphalt. Roof pitch is the measurement of a roof s vertical rise divided by its horizontal run. 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.

The members making up the main body of the framework of all roofs are called rafters. Contact flexospan for information on custom purlin and girt structural steel dimensions. Steel roof purlins and wall girts are produced and available in house.