Standard Roof Truss Angles

Commonly it is 3 4 th of span as per gothic rafter must be equal to span.

Standard roof truss angles.

We can also build a cantilever for the overhang which is where the bottom chord of the truss continues beyond the wall. Greek says one must keep rafter length in range of 1 9 to 1 7 th of span but as per roman style the standard dimensions are kept about 1 3 to 2 9 th of span with an angle of 23 to 24 degree. Pitches above 9 12 are very highly angled and are designated steep slope roofs. 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.

A standard overhang is 16 24 inches but the overhang can be any length you wish. A mono truss roof allows for more sunlight and visual space proper drainage and relatively cheaper. Pitches of less than 2 12 are considered flat roofs even though they may be very slightly angled. Pitches lower than 4 12 have a slight angle and they are defined as low slope roofs.

A truss with the same pitch and heel on both sides and a peak at the center is called a common truss. If the overhang exceeds 2 5 feet we will need to use a larger top chord for the overhang typically a 2 6 top chord for the truss. A mono truss is a one sloped truss that forms a right angle triangle. This is useful because sometime you may need to cut a bevel with your circular saw that is not calibrated using roof pitch style this setting on circular saws is calibrated in degrees.

This means if a roof rises 4 in the length of 12 your roof pitch would be 4 12 or 18 43 degrees. The most commonly used roof pitches fall in a range between 4 12 and 9 12. This forms an angle of 18 5 between the horizontal section and the roof and creates a gentle incline that is seen as a midpoint between a low pitch and medium pitch roof. Common or standard trusses are symmetrical and have standard four inch heels.

A 4 12 is a roof slope that rises by 4 inches for every 12 inches across. Roof pitch and corresponding angles. Usually average roof pitch is determined using the same roof length method. Angle the angle of a roof is the same as the roof s slope except instead of being represented as x 12 it is represented in degrees.

This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement. The truss is a framework consisting of rafters posts and struts which supports your roof.