How To Measure Up For Roof Trusses

For example a roof with a span of 20 ft and a rise of 7 feet needs rafters that are the square root of 400 49 21 2 feet.

How to measure up for roof trusses.

Starting at one end of the roof mark the first truss flush with the outside edge of a cap plate. For example if the pitch is 4 and the span is 9 feet 6 inches r 4 9 5 12 3 167 feet. Trusses can be constructed with smaller sized lumber than rafters and often their cost is not significantly higher than normal rafters. Already having the rise will make it easy to determine the rafter length by loading the numbers into the equation chart.

Equation a2 b2 c2. Trusses are generally secured 24. For a 9 m 30 foot long roof a total of 15 trusses are needed. Pull a tape measure along the top plate of the house to determine the length of.

On a ladder beside the roof place the level a foot or so up the roof hold it level and measure from the 12 inch mark on the level s bottom straight down to the roof. Measure as precisely as possible down to the 1 4 inch 0 64 cm 1 8 inch 0 32 cm or 1 16 inch 0 16 cm. Overall span wall to wall bottom chord length if different than the wall to wall span overhang length. Measure out 5 to 6 trusses at a time.

Hammer a nail in place to hook your measuring tape and space out the subsequent trusses every 2 feet or other designated spacing. Set two ladders at each end of the area to be measured. How to measure roof trusses. C rafter length.

If this distance measures 4 inches you have a 4 in 12 pitch. Divide the length of the roof by two to determine how many trusses are needed. Use a tape measure to measure the entire width of your building. Pitch measurement method 1.

Before you start cutting you first need to determine how long your roof rafters need to be and the angles at which you ll cut the top and bottom of the rafter. Use a level square and measuring tape. Converting that to feet and inches the rise is 3 feet 2 inches. Use of manufactured roof trusses can dramatically cut labor costs when framing a gable roof compared to building rafters.

Divide the length of the roof by two to determine how many trusses are needed.