2 5 12 Roof Pitch
The combination of two numbers are used to display or show the roof pitch.
2 5 12 roof pitch. This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement. Pitch is thus the ratio of the rise in inches to a 12 inch run and is often expressed using a semicolon for example 6 12. A pitch of 2 12 is the minimum pitch for shingles made of asphalt so your roof just barely makes the cut off for one of the most popular roofing material options. A roof with a 6 rise for every 12 run has a 6 per foot or 6 in 12 pitch.
Resilient asphalt shingles lie much flatter to the substrate than slate tile and concrete which keeps water from being easily blown under them. Asphalt shingles continue to be the most widely installed roof covering option in north america. They provide excellent weather resistance great value and now more than ever a tremendous range of beautiful designs and color blends. 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 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. The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles. 2 5 12 to 19 12 pitches clay or cement tiles can be used on a wide range of roof pitches. For pitches of 2 5 12 up to 4 12 the roof requires double underlayment.
Roof pitch or slope is a measure of vertical rise to horizontal run expressed in inches per foot.