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.
Normal roof pitch.
Display of roof pitches 1 12 through 18 12.
4 12 to 20 12 pitches.
Slopes above 19 12 are not recommended since tiles on very steep roofs can rattle.
With insufficient pitch a roof can leak rain and with a pitch too great its stones will fall loose.
The minimum pitch for a roof is 1 4 12 which translates to 1 4 inch rise to 12 inches of run.
The pitch of the roof is determined by the vertical rise in inches for every horizontal twelve inch length.
Most roofs in america follow these dimensions where pitch range is kept between 3 to 7 1 2.
Clay or cement tiles can be used on a wide range of roof pitches.
The most commonly used roof pitches fall in a range between 4 12 and 9 12.
Pitch is a measure of the steepness of a roof.
Pitches of less than 2 12 are considered flat roofs even though they may be very slightly angled.
In the usa the range of standard pitches is anywhere between 4 12 and 9 12.
An average person can easily and safely walk upon these roofs without need of additional equipment.
Thatch is one of the oldest roofing materials and needs a steep pitch to drain properly some types of stone roofs have a very restrictive roof pitch.
If you want to build a shed garage or other similar type of building then 4 to 6 is a preferable pitch type.
A flat roof would have a 2 12 pitch while the average roof pitch would be between 4 12 and 9 12.
So the pitch of a roof is determined by how many inches the slope rises for every 12 inches it runs horizontally.
Pitches above 9 12 are very highly angled and are designated steep slope roofs.
For pitches of 2 5 12 up to 4 12 the roof requires double underlayment.
This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement.
In the uk the typical house has a pitch between 40 50 although 45 should be avoided.
However you can only use this pitch with built up roofing or specialized synthetic roofing.
If a roof increases in height by four inches for every foot of horizontal run it is considered to have a 4 in 12 pitch or just a 4 pitch talk in terms of pitches and you will always be understood in the roofing universe.