Express the slope of a metal roof by a ratio which indicates the pitch of the roof.
Minimum roof pitch oregon.
They provide excellent weather resistance great value and now more than ever a tremendous range of beautiful designs and color blends.
The minimum slope of a roof depends on the roof s profile.
Metal roof shingles require a minimum roof pitch of 3 12 or greater.
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.
With regards to metal roofing the profile refers to the shape adopted by the metal sheets when they are bent to form the panels.
Gabled hipped or gambrel roof where roof pitch is 12 in 12 or less.
This 1 4 12 minimum roof slope requirement also applies to spray polyurethane foam spf roof systems in new construction.
However you can only use this pitch with built up roofing or specialized synthetic roofing.
Measure to the average height of the highest gable.
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.
See the map usage notes or snow load analysis for oregon part ii for further information.
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.
Let us recap on the minimum roof pitch required for each type of roofing material.
Minimum pitch for metal roof.
The profile is the shape taken by the sheets when you bend them to form panels.
For metal panel roof systems with nonsoldered seams with applied lap sealant ibc 2018 prescribes a 1 2 12 minimum roof slope.
Minimum roof snow load.
Minimum requirements other than density are calculated as.
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.
Clay and concrete tile requires a minimum roof pitch of 2 1 2 12 or greater.
For standing seam metal roof panel systems a 1 4 12 minimum roof slope is prescribed.
The minimum pitch for a roof is 1 4 12 which translates to 1 4 inch rise to 12 inches of run.
You need to consider the slope requirements of each panel to determine this minimum slope.
Asphalt shingles continue to be the most widely installed roof covering option in north america.
To get the minimum pitch for a metal roof the vertical rise per foot is divided by the horizontal slope.
You could also opt for a pvc flat roofing membrane.
Asphalt shingles require a minimum roof pitch of 2 12 or greater.
