How To Measure Up For Roof Trusses

For a 9 m 30 foot long roof a total of 15 trusses are needed.

How to measure up for roof trusses.

How to measure roof trusses. C rafter length. Trusses can be constructed with smaller sized lumber than rafters and often their cost is not significantly higher than normal rafters. Trusses are generally secured 24.

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. Set two ladders at each end of the area to be measured. Divide the length of the roof by two to determine how many trusses are needed. Pitch measurement method 1.

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. In order to match up to an existing building there s a couple different measurements that are needed so that you will end up with a matching roof addition. 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. Use a tape measure to measure the entire width of your building.

Hammer a nail in place to hook your measuring tape and space out the subsequent trusses every 2 feet or other designated spacing. Use of manufactured roof trusses can dramatically cut labor costs when framing a gable roof compared to building rafters. Measure out 5 to 6 trusses at a time. Pull a tape measure along the top plate of the house to determine the length of.

Already having the rise will make it easy to determine the rafter length by loading the numbers into the equation chart. Step 1 find the total rise of the roof using the formula r ps 12 where r is the rise p is the pitch and s is the span. Use a level square and measuring tape. If this distance measures 4 inches you have a 4 in 12 pitch.

Equation a2 b2 c2. 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. 8 inches and you have an 8 in 12 pitch. Divide the length of the roof by two to determine how many trusses are needed.

For example if the pitch is 4 and the span is 9 feet 6 inches r 4 9 5 12 3 167 feet.