Use this 3 part SimpleSpecs™ master specification to specify natural slate shingles and underlayment.
These shingles have a long life expectancy and are available in three classes based on the required life expectancy. Slate is a fine-grained metamorphic rock with no apparent compositional layering but can easily separate into thin slabs and plates.
Shingles are extremely heavy and require significant structure to support them. Before specifying these products, consult with a professional engineer to determine framing and sheathing requirements.
Underlayment requirements vary depending on the roof slope, from a single layer of roofing felt to rubberized asphalt and synthetic. Similarly, valley construction varies depending on the slope of the roof.
For selection and detailing of slate shingles, refer to the National Roofing Contractors Association (NRCA) Roofing Manual: Steep-Slope Roof Systems, available from NRCA at www.nrca.net.
To learn more about slate, visit Wikipedia.
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