Slate on Fire: Can it be Reused?

By Evelyn Witterholt. 

Learn all about how slate interacts with fire and if it can be salvaged afterwards. 

It’s common knowledge that slate is fire-resistant, but can it be reused after it interacts with fire? The answer is a bit complicated as there are many factors to consider, such as the condition of the slate or its proximity to fire. The National Slate Association (NSA) outlines all the considerations to make when it comes to reusing slate after a fire in their technical bulletin, “Reuse of Slate Shingles Exposed to Fire”. 

In the bulletin, the NSA outlines the impressive fire-resistant properties of slate roof tiles. For decades, slate roof shingles were considered effective against fire exposure. But in 2009, when it was called into question over whether or not slate was effective against fire when installed over combustible roof decks, the NSA performed further testing. 

The bulletin states that once fire tests were performed again, “Slate shingles installed over a combustible roof deck were once again recognized as having a Class A rating over combustible decks in the 2015 edition of the International Building Code.” 

Although slate tiles themselves will not combust, the question of whether slate exposed to fire can be reused still remains. According to the bulletin, there is no universally accepted answer. A lot of factors must be taken into consideration, including the type of slate used, its age or its condition. 

One consideration the NSA encourages you to take into account is the previous condition of the slate. They state that “a slate nearing the end of its service life, based on age or as evidenced by significant surface delamination, cracking, and broken corners on the exposed faces, is probably not a good candidate for salvage and reuse, regardless of whether it has been exposed to fire, or not.” 

Check out the entire technical bulletin from NSA to learn more about if slate can be reused after being exposed to fire.