The minimum roof slope requirement for metal panels varies depending on panel connection conditions. The required roof slope varies with application of materials and use. See the below Florida Building Code 7th Edition (2020) sections below to determine which slope is appropriate based on your specific design scenario.
Definition
METAL ROOF PANEL. An interlocking metal sheet having
a minimum installed weather exposure of 3 square feet
(0.279 m2) per sheet.
Code References
1507.4 Metal roof panels. The installation of metal roof panels
The installation of metal roof panels shall comply with the provisions of this section. Metal roofing panels shall be factory or field manufactured in accordance with the manufacturers’ product approval specifications and limitations of use. Metal roofing panels shall be factory or field manufactured under a quality assurance program that is audited by a third-party quality assurance entity approved by the Florida Building Commission for that purpose.
1507.4.1 Deck requirements. Metal roof panel roof coverings
shall be applied to a solid or closely fitted deck, except where the roof covering is specifically designed to be applied to spaced supports.
1507.4.2 Deck slope. Minimum slopes for metal roof panels
shall comply with the following:
- The minimum slope for lapped, nonsoldered seam metal roofs without applied lap sealant shall be three units vertical in 12 units horizontal (25-percent slope).
- The minimum slope for lapped, nonsoldered seam metal roofs with applied lap sealant shall be one-half unit vertical in 12 units horizontal (4-percent slope).
Lap sealants shall be applied in accordance with the approved manufacturer’s installation instructions. The minimum slope for standing seam of roof systems shall be one-quarter unit vertical in 12 units horizontal (2-percent slope).
1507.5.2 Deck slope. Metal roof shingles shall not be installed on roof slopes below three units vertical in 12 units horizontal (25-percent slope).
1507.6.2 Deck slope. Mineral-surfaced roll roofing shall not be applied on roof slopes below one unit vertical in 12 units horizontal (8-percent slope).
1507.10 Built Up Roofs Built-up roofs shall have a design slope of not less than one-fourth unit vertical in 12 units horizontal (2-percent slope) for drainage, except for coal-tar built-up roofs that shall have a design slope of not less than one-eighth unit vertical in 12 units horizontal (1-percent slope).
1523.6.5.2.4 Metal shingles/panels. All metal roofing shall be tested in compliance with TAS 100. All metal roofing shall resist a minimum wind uplift resistance as determined by Chapter 16 (High- Velocity Hurricane Zones) for a roof slope of 9.5 degrees (0.0166 rad) and a roof mean height of 15 feet (4.6 m).
1523.6.5.2.6 Fiber cement shingle or tile panels.
All fiber cement shingles or tiles shall resist a minimum wind uplift resistance as determined by Chapter 16 (High-Velocity Hurricane Zones) for a roof slope of 9.5 degrees (0.0166 rad) and a roof mean height of 15 feet (4.6 m).
In Type I and II construction, sloped glazing and skylight frames shall be constructed of noncombustible materials. In structures where acid fumes deleterious to metal are incidental to the use of the buildings, approved pressure-treated wood or other approved noncorrosive materials are permitted to be used for sash and frames. Framing supporting sloped glazing and skylights shall be designed to resist the tributary roof loads in Chapter 16. Skylights set at an angle of less than 45 degrees (0.79 rad) from the horizontal plane shall be mounted at least 4 inches (102 mm) above the plane of the roof on a curb constructed as required for the frame. Skylights shall not be installed in the plane of the roof where the roof pitch is less than 45 degrees (0.79 rad) from the horizontal.
Exception: Installation of a skylight without a curb shall be permitted on roofs with a minimum slope of 14 degrees (three units vertical in 12 units horizontal) in Group R-3 occupancies. All unit skylights installed in a roof with a pitch flatter than 14 degrees (0.25 rad) shall be mounted at least 4 inches (102 mm) above the plane of the roof on a curb constructed as required for the frame unless otherwise specified in the manufacturer’s installation instructions.
Last Update: March 30, 2021