Roof Slope Factor Table

This article series gives clear examples just about every possible way to figure out any or all roof dimensions and measurements expressing the roof area width length slope rise run and unit rise in inches per foot.

Roof slope factor table.

The square root of 180 is 13 416. The roof slope factor can be determined through sections 7 4 1 through 7 4 4 of asce 7 10 and can be known as. Accurate roof calculations are achieved using this table and all you need to do is measure the roof width and length and then you are ready to do a roof pitchmeasurement. Roof slope pitch rise run typw walkability table.

For example if you measure 4 inches the pitch of your roof is 4 12. See below after the table for directions on how to convert any roof slope from one form to another. Place the level at the center of the top ridge. Although there s isn t any standard pitch of a roof used on all kinds of sloped roofs you can determine the range of pitches by using a roof angle calculator and by considering factors like the local climate and roofing materials.

Take a ladder and reach to the top of the roof. This will give you the rise over run or pitch. Two most common methods 4 12 or 4 12 are used for marking the pitch of a roof. The roof pitch multiplier table is very helpful in giving correct and reliable roof measurements and uses pythagorean theory.

This table shows the roof pitch multiplier also called the roof pitch factor for typical roof slopes used to find the area of sloped roofs or the lengths of common rafters. On blue prints architects engineers usually display the pitch of a roof in the format shown on the image where number 4 represents a rise and number 12 represents a length. The following table shows how the same common roof slopes can be expressed using rise in run ratios degrees and percentages. You can tie the ladder to the gutter or the fascia board.

Adding 36 plus 144 equals 180. Suppose you have a 6 12 pitch roof. Simply locate a roof rafter board place the end of the level against the bottom edge and measure from the 12 inch mark vertically to the bottom edge of the rafter. Six squared is 36 and 12 squared is 144.

From here note down the reading of the level to the. Dividing 13 416 by 12 equals 1 118. This table lists all of the common roof slopes expressed as rise run roof angle roof slope slope grade and walk ability. Roof pitch refers to the measurement of the slope of a roof and you express this as a ratio.

Warm roof slope factor cold roof slope factor. Therefore your slope factor for a 6 12 pitch roof is 1 118.