Conversion Tables and Charts
Conversion Tables and Charts
1 Roofing Slopes
Fall/Run Slope Ratio Inch / Foot mm / m Percentage Slope Angle Degrees / Minutes 1:1 12" in 12" 1000.0 100.0 45 - 00 1:2 6" in 12" 500.0 50.0 26 - 34 1:3 4" in 12" 333.3 33.3 18 - 26 1:4 3" in 12" 250.0 25.0 14 - 02 1:5 -- 200.0 20.0 11 - 19 1:6 2" in 12" 166.7 16.7 9 - 28 1:7 -- 142.9 14.29 8 - 08 1:8 1-1/2" in 12" 125.0 12.5 7 - 08 1:9 -- 111.1 11.1 6 - 20 1:10 1-1/2" in 12"* 100.0 10.0 5 - 43 1:11 -- 90.9 9.09 5 - 12 1:12 1" in 12" 83.0 8.3 4 - 46 1:13 -- 76.9 7.69 4 - 24 1:14 -- 71.4 7.14 4 - 05 1:15 3/4" in 12"* 67.0 6.7 3 - 49 1:20 5/8" in 12"* 50.0 5.0 2 - 52 1:25 1/2" in 12"* 40.0 4.0 2 - 17 1:30 -- 33.3 3.33 1 - 55 1:40 -- 25.0 2.5 1 - 26 1:50 1/4" in 12"* 20.0 2.0 1 - 09 1:60 -- 16.7 1.67 0 - 57 1:80 -- 12.5 1.25 0 - 43 1:100 1/8" in 12"* 10.0 1.0 0 - 34 * (Nominal) © RCABC 2024
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