Metal Flat Roof Minimum Slope

The minimum slope for lapped non soldered seam metal roofs with applied lap sealant shall be one half unit vertical in 12 units horizontal 4 percent slope.

Metal flat roof minimum slope.

For low slope metal roofs under 12 that are nearly flat modified bitumen roofing thermoset and thermoplastic single ply are approved and recommended. Moreover low slope metal roofs are not prone to the degradation experienced by organic materials enabling these roofs to better resist the elements. With regards to metal roofing the profile refers to the shape adopted by the metal sheets when they are bent to form the panels. After that the miimum pitch for metal panels depending on the methods used to join the panels.

The following table provides the minimum required allowable roof slope for each type of roofing material mentioned in the code. Low slope roofs are not totally flat their roof slope generally ranges from 1 4 12 to 3 12. Normally 1 80 0 72 is the recommended minimum angle for a slope and this is universal across the vast majority of flat roofing systems regardless of the materials that they incorporate. Minimum metal roof slope depends on the roof profile building design climate and site location.

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 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. This means for every 12 horizontal units the roof must rise a minimum of 3 vertical units. In retrofit projects a sub framing system is attached to the existing flat roof surface to provide a minimum 12 roof pitch.

Profile in the context of metal roofing means the shape that the sheet of metal is bent into to form the panels. Lapped nonsoldered seam metal roofs without applied lap sealant must have a minimum roof slope of 3 12 25 slope. To get the minimum pitch for a metal roof the vertical rise per foot is divided by the horizontal slope. Panels joined with an applied lap sealant can go as low as 12.

Units vertical in 12 units horizontal 25 percent. Metal roofs with applied lap sealant shall be one half. The minimum roof slope allowed by code for any type of roof is in 12 applicable only to coal tar pitch roof systems. The minimum roof slope for metal roof panels depend on 3 different scenarios.

The minimum slope for lapped nonsoldered seam. Typically large footprint single story warehouses and pre engineered metal buildings will utilize low slope metal roof systems. The minimum roof slope for metal roofs is dependent upon the roof profile.