Express the slope of a metal roof by a ratio which indicates the pitch of the roof.
Minimum roof pitch oregon.
Let us recap on the minimum roof pitch required for each type of roofing material.
Asphalt shingles continue to be the most widely installed roof covering option in north america.
However you can only use this pitch with built up roofing or specialized synthetic roofing.
Asphalt shingles require a minimum roof pitch of 2 12 or greater.
Minimum roof snow load.
Measure to the average height of the highest gable.
The profile is the shape taken by the sheets when you bend them to form panels.
This 1 4 12 minimum roof slope requirement also applies to spray polyurethane foam spf roof systems in new construction.
This may not be reduced for slope or any other conversion factor and may be only modified where applicable by a rain on snow surcharge oregon structural specialty code ossc section 1608 1.
Clay and concrete tile requires a minimum roof pitch of 2 1 2 12 or greater.
Metal roof shingles require a minimum roof pitch of 3 12 or greater.
You could also opt for a pvc flat roofing membrane.
They provide excellent weather resistance great value and now more than ever a tremendous range of beautiful designs and color blends.
To get the minimum pitch for a metal roof the vertical rise per foot is divided by the horizontal slope.
For standing seam metal roof panel systems a 1 4 12 minimum roof slope is prescribed.
Minimum requirements other than density are calculated as.
Oregon structural specialty code the uniform building code as amended by the state.
The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles.
There are some standing seam metal roofing options available from atas and other manufacturers that can be installed on a roof with pitch of 1 12.
With regards to metal roofing the profile refers to the shape adopted by the metal sheets when they are bent to form the panels.
The minimum slope of a roof depends on the roof s profile.
See the map usage notes or snow load analysis for oregon part ii for further information.
Minimum pitch for metal roof.
The minimum roof slope for metal roofs is dependent upon the roof profile.
For metal panel roof systems with nonsoldered seams with applied lap sealant ibc 2018 prescribes a 1 2 12 minimum roof slope.
The minimum design roof snow load for all structures in oregon is 20 pounds per square foot psf.
The minimum pitch for a roof is 1 4 12 which translates to 1 4 inch rise to 12 inches of run.
Oregon requires a minimum roof snow load of 20 psf pm in asce7 for all roofs plus a 5 psf rain on snow surcharge for many roof types resulting in a 25 psf minimum roof design load for most roofs.
