Consider relocating mechanical equipment that might be mounted on the roof.
Consider replacing flat or low-slope roofs with pitched roofs: fewer leaks,
less frequent repair, better insulation.
Do not design low-slope roofs (less than 3 inches per foot slope) unless
absolutely necessary.
Overlapping metal roofs should not be designed for large buildings.
If metal
roofing becomes necessary, standing seam type should be used.
Corrugated metal roofing with protective coating should be guaranteed for 15
years. Ensure fasteners are not placed at low points of corrugations and
sealing washers are used.
For corrugated metal roofs, also see Building Exterior - Metal Siding.
For built-up roofing design, use master specification contained in AFM 91-36.
Design details for BUR accessories and metal roofs to avoid dissimilar metals
contact.
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