Keep in mind that neither metal shingles not corrugated metal panels are suitable options for low slope or nearly flat roofs.
Minimum snow slope roof pitch.
The minimum slope for standing seam of roof systems shall be one quarter unit vertical in 12 units horizontal 2 percent slope.
Run in degrees and as percentage the minimum roof slope allowed by code for any type of roof is in 12 applicable only to coal tar pitch roof systems.
A minimum slope of 1 inch per foot is recommended in snow country.
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.
However roof pitch is technically measured and defined differently.
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.
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.
Roof slope equivalents as rise.
Note that roof pitch is sometimes used in parallel with roof slope.
This can be accomplished by measuring the number of inches the roof rises vertically for every 12 inches it extends horizontally.
I e 4 inches of rise per 12 inches one foot of run.
A minimum pitch of 3 in 12 or even 4 in 12 will normally be required.
Importance of a roof pitch.
Depending on the roof profile there are minimum roof slope requirements for each panel which need to be considered.
The following table provides the minimum required.
Low pitch roofs are seldom used in regions of severe weather due to the stress of snow accumulation on roofs of structures.
The minimum pitch for a roof is 1 4 12 which translates to 1 4 inch rise to 12 inches of run.
The 1 4 inch per foot slope was not adequate.
There are some opinions that standing seam metal roof minimum slope is 12 but it increases the possibility of leaking on the few first days of snow arrival.
The minimum roof pitch is also subject to the standards set forth by the various building codes used in the respective regions.
If a roof slope rises say 4 inches when measured 12 inches along the bottom of a horizontal roof truss the roof slope is said to be 4 12.
In country with heavy snow and tough winter days the metal roof minimum slope is recommended to be 1 12.
The profile refers to the shape the metal sheets take when they bend to.
However you can only use this pitch with built up roofing or specialized synthetic roofing.
