NRCA and the National Slate
Association (NSA) recently conducted limited fire testing of slate
roof systems. If you supply, design or install slate roof systems,
I encourage you to be aware of the building code-related
circumstances that necessitate this work and the test results.
In the International Building Code, 2009 Edition (IBC
2009), an exception from fire testing in the code's previous
editions was removed. The exception waived slate roofs from fire
testing to determine their fire classifications. With IBC 2009,
newly installed slate roof systems installed on combustible roof
decks need to be tested and have a listing of their fire
classifications. For additional information, see "New fire
classifications," April issue, page 24.