Roof Truss Layout Measurements

This conforms to the 4 by 8 foot dimensions of plywood or oriented strand board osb sheets used to deck or cover the roof in preparation for shingles.

Roof truss layout measurements.

The truss is a framework consisting of rafters posts and struts which supports your roof. There are other types of roof trusses that require different measurements. The run or the base number is 12 inches. The very first step for building roof trusses is to prepare a design layout that can be sketched by a professional architect or can also be done by using a software that is specifically meant to design a roof truss.

These will include wood a hammer a saw roof truss. These measurements are for a common roof trusses. Your top chords can protrude beyond the bottom chord anywhere from 1 3 feet 0 30 0 91 m. For example a slope of 6 12 means for every 12 inches of horizontal distance the slope of the roof will rise 6 inches vertically.

Use of manufactured roof trusses can dramatically cut labor costs when framing a gable roof compared to building rafters. See the image below for more explanation on rise run and pitch. If you think you d prefer an overhang style truss adjust the measurements for your top chords accordingly. Thus a moderate 6 in 12 roof pitch means that the roof rises 6 inches vertically for every 12 horizontal inches it runs.

To obtain the actual height of the truss deduct the height of the wall from the total number calculated on the roof truss calculator see resources. Trusses can be constructed with smaller sized lumber than rafters and often their cost is not significantly higher than normal rafters. The second step in building a roof truss is to prepare the materials needed. A 12 in 12 pitch is a steep 45 degree angle roof.

Pitch slope the pitch or slope is the incline of the roof expressed as a fraction describing the rise over the run. A roof s pitch is determined by how much it rises vertically for every foot it runs horizontally. Improperly spaced trusses will not provide correct nailing points to secure decking. The rise will be the elevation change over the 12 inches.

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.