It is determined based.
Shed roof pitch snow load.
Constructing a new shed roof at the desired pitch is as easy as knowing how to use a speed square.
Personally unless you live in an area of extreme snow load i would recommend you incorporate a shed roof pitch of between 4 12 and 6 12 for optimum results.
As stated in the video speed squares have useful markings on them from 0 to 12.
Remember that pitch is calculated as the height or rise of a roof pitch over 12 inches of horizontal run.
Roof snow load is defined as the weight of snow on the roof surface used in design of the building structure ibc 2012.
This will extend the life of your roof.
Ground snow load value.
Therefore if your roof rises 4 inches over the course of 12 inches of horizontal run then your roof pitch is 4 12.
The flip side to this is that it also becomes more expensive to build both in materials and logistical difficulty.
Wind exposure of roof.
This range makes up the bulk of new roofs being built on homes and outbuildings in the u s.
If you are building a new roof however consider the climate to determine the correct pitch and proper materials.
A medium pitched roof is one that has a pitch of between 3 12 and 7 12.
Slopes greater than 6 12 will tend to shed snow regardless of the texture of the material on them so roof slopes should be configured to avoid shedding anywhere people might be walking or exiting.
If necessary rebuild or fortify them to withstand worst case scenario snow loads and meet local building standards.
Basically the steeper the pitch the better it can shed snow and rain.
The key factors are usually snow loading requirements adequate slope and the use of snow guards when needed.
Importance occupancy and use of the building.
The safest way to determine the pitch of an existing roof is to measure from inside your attic using a level tape measure and pencil.
If these issues are addressed during the design stage and the roofing contractor does his job these systems will almost always perform as intended.
For example a roof with 3 feet of light snow has an estimated roof load of 60 pounds per square foot 3 ft depth x 20 lb ft2 ft depth density 60 lb ft2.
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.
On multiple factors including.
Metal roofing systems have a good track record of performance in harsh winter environments as long as they are properly designed.
So in general the shallower pitch can be more dangerous with bigger slides.