In the roofing trade the go to term is pitch and it is expressed in terms of 12 inches so the pitch of a roof is determined by how many inches the slope rises for every 12 inches it runs horizontally.
Roof angle for snow.
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.
Pitch angle incline slope they all can be used to refer to the steepness of a roof.
A steep slope roof is one whose slope is greater than 3 12.
These are also the most common pitches for shed roofs.
Again the most important consideration is the weather.
The minimum roof pitch is also subject to the standards set forth by the various building codes used in the respective regions.
Steeper slopes are ideal for areas that have higher snow loads and will also prevent the possibility of ponding water on the roof.
Use a handy tool like snow load calculator to help you determine if your roof can handle the weight of snow based on its pitch.
On multiple factors including.
Importance of a roof pitch.
The flip side to this is that it also becomes more expensive to build both in.
Any roof from 4 12 to 9 12 is considered an ordinary angle for a roof.
Wind exposure of roof.
Ground snow load value.
The chief reason for having a roof pitch is to redirect water and snow away from the roof and avoid any percolation that might result from stagnation of water on the roof.
Roof snow load is defined as the weight of snow on the roof surface used in design of the building structure ibc 2012.
When it comes to residential construction your roof is a visible part of the structure.
Importance occupancy and use of the building.
For example a roof with a 6 inch 12 pitch is one where it rises 6 inches vertically for every 12 inches of the horizontal run.
This can be accomplished by measuring the number of inches the roof rises vertically for every 12 inches it extends horizontally.
It is determined based.
The minimum roof pitch for shedding snow is around 30 or a 6 12 or 7 12 slope although this is not a definite as the material of your roof the direction of the snow and wind are some factors that can affect whether or not snow will slide as roofs of as little as 10 have been reported to shed snow.
Basically the steeper the pitch the better it can shed snow and rain.
There are advantages and disadvantages to having a steep pitch versus a shallow or low pitch the most obvious of which is the roof s ability to shed or withstand heavy snow rain or wind.