Standard Lean To Roof Pitch

They have a pitch ranging from 4 12 to 9 12.

Standard lean to roof pitch.

Enter this measurement into the calculator and select a roof pitch and the length of the rafter will automatically returned along with the rise. You can safely measure the roof pitch from inside your attic with a level that is either 18 or 24 inches a tape measure and a pencil. For example if the level is 4 above the roof at a point 12 away from where the level is touching the surface then the pitch is 4 12. You can also divide the rise over run multiply by 100 and get a percentage.

A 4 12 pitch is around 18 5 degrees but not exactly. Minimum roof pitch for shingles. Begin by measuring 12 inches on your level and marking it with a pencil. The minimum pitch for a roof is 1 4 12 which translates to 1 4 inch rise to 12 inches of run.

Once in the attic hold your level against the bottom of a roof rafter ensuring that all bubbles are resting in the center. A ratio is the most common way of expressing roof pitch or roof slope but degrees are also possible. Conventional roofs are the easiest to construct and you can walk on them safely. You can also calculate roof pitch even without using a roof slope calculator.

On the roof hold the level perfectly level and measure the height from the roof to the level 12 inches away from where the level touches the surface this will be the rise. This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement. With regards to the pitch the building standard code bs 5534 recommends a minimum pitch of 200 for slate roofs. But since there is still a wide variety of slate roofing systems there are occasions when the minimum pitch can go down to as low as 15 0 depending on the uniqueness of the roof.

Thus a 4 12 pitch would be a 33 slope. 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.