Minimum metal roof slope depends on the roof profile building design climate and site location.
Low pitch low slope metal roof.
Low slope metal roofs have been a preferred roof covering for commercial institutional and industrial buildings for years because of their ability to protect against the elements to allow water to drain away from the roof surface and to keep building contents and occupants dry and comfortable.
The minimum pitch is typically 3 12 meaning the roof should rise 3 inches for every 12 inches of horizontal foot.
Structural metal panel roof systems can be used for low slope roofs because of their hydrostatic or water barrier characteristics.
At sheffield metals we also recognize low slope as 3 12 and below.
Low slope metal roofs require less material which reduces the overall load on the building s structure.
Low slope roofs are not totally flat their roof slope generally ranges from 1 4 12 to 3 12.
Because of the shallow height of the undulating ridges of the 5v and corrugated profiles and the use of exposed metal fasteners to screw the metal to the roof deck they are limited to a slope that will shed rain quickly.
But the taller profiles like standing seam and pbr shown below can be installed on roofs with as low as 1 4 or 1 2 in 12 pitch.
Determining which panel is the right choice for the slope on your project will depend on the manufacturer s minimum slope factor for that specific panel profile.
The panels have been designed for application over a wide variety of substrates on roof slopes as low as 1 2 12 pitch.
Most structural metal panel roof systems are designed to resist the passage of water at laps and other joints as sealant or anti capillary designs can be used in the seams.
Low slope metal roofs have simple geometries and are easier and less expensive to install that medium to steep slope roofs.
It is important to note structural metal panel roof systems can be used for steep slope roof assemblies too.