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Here's an area you might not normally think about when thinking about fire safety: the roof. I know this might be controversial when it comes to fire safety, but as with anything there might be a point where more isn't better but is just more.
According to your local fire code, the location of the building within a fire district may dictate what class of fire rating is required. To be sure, the fire rating needs to be checked carefully to be sure the whole assembly — deck, insulation and membrane — meets the description in the fire classification ratings.
Here's where you might be getting more roof than required by the level of fire safety needed. Often, roofers just put a Class A rated roof system on any building. This means that if you don't need a Class A rated roof, you will spend extra money that you don't need to spend.