So in general the shallower pitch can be more dangerous with bigger slides.
Minimum pitch for metal roof snow slide off.
Begin by measuring 12 inches on your level and marking it with a pencil.
The minimum slope for lapped non soldered seam metal roofs without applied lap sealant shall be three units vertical in 12 units horizontal 25 percent slope.
The recommended minimum roof pitch for shingles is 2 12 or simply two units of vertical rise to every twelve units of horizontal span.
The higher the roof pitch the more often the snow slides off.
You can safely measure the roof pitch from inside your attic with a level that is either 18 or 24 inches a tape measure and a pencil.
Corrugated metal roofing has the same minimum pitch.
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.
However it is regrettable that many installers usually ignore this requirement due to the desire for a quick installation process.
Minimum pitch for metal roof for the most part the minimum pitch for metal roof installations depends on what kind of material you are installing and the method in which the material is being fastened.
That is a 14 degree angle.
Roof pitches of 3 12 4 12 5 12 or 6 12 work best for metal buildings in snow country.
They would say use a low slope approximately 5 12 and keep the snow on.
Anything over a 6 12 pitch tends to make massive amounts of snow slide off the roof without warning.
In an effort to solve the problems associated with moving snow and ice i have heeded the experience and resources of european construction industry and have implemented their ideas with great success.
The minimum pitch for metal roof shingles and lapped non soldered panels is 3 12.
That means there is at least 3 of vertical rise to the roof slope for every 12 it goes back horizontally.
The pitch is measured in inches of vertical rise per foot of horizontal run and the 5v crimp profile shown above requires a minimum slope of three in twelve or 3 12 3 inches vertically per 12 inches horizontally.
Standing seam metal roofs which allow snow to slide more easily might do.
Once in the attic hold your level against the bottom of a roof rafter ensuring that all bubbles are resting in the center.