The basic explanation is that most roofs have a slope and the degree of steepness associated with the slope is called pitch.
Pitch and elevation of roof.
For example if the roof rises 4 feet and the span is 16 feet twice the run then the pitch is 4 16 or 1 4.
So the pitch of a roof is determined by how many inches the slope rises for every 12 inches it runs horizontally.
You can also calculate roof pitch even without using a roof slope calculator.
Squaring building lines example 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.
High pitched roofs often need extra fasteners and their pitch can be as high as 21 12.
Understanding a roof s pitching can be quite tough if you are just getting started and working with a roofer can leave you a little bit unsure about what is being suggested with regard to the job there s so much to learn that it can become a bit baffling.
Pitches above 9 12 are very highly angled and are designated steep slope roofs.
One of the most important aspects of trying to get the roof right though is the pitch.
Conventional roofs are the easiest to construct and you can walk on them safely.
This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement.
A roof that rises 8 feet over a 24 foot span was said to have a 1 to 3 pitch.
Pitches lower than 4 12 have a slight angle and they are defined as low slope roofs.
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.
Pitches of less than 2 12 are considered flat roofs even though they may be very slightly angled.
A roof similar to a mansard but sloped in one direction rather than both.
They have a pitch ranging from 4 12 to 9 12.
The steep slope may be curved.
The pitch fraction represents a certain amount of vertical rise over the entire span.
If the rise is 4 feet over a 24 foot span then the roof pitch was said to be 1 to 6 the pitch can be expressed numerically as a fraction.
The most commonly used roof pitches fall in a range between 4 12 and 9 12.