OP, are you with Intact or someone else?
Intact was (to my knowledge) the first company to implement the roof depreciation. I can't speak for all insurance companies but I know Intact has the endorsement listed right on the coverage page. I think the phrase is "roof limitation endorsement" or something like that. They've been using this for two or three years now. At the moment they are the only company we deal with that has it but I know there are a handful of others in the industry who have adopted the same approach (Wawanesa maybe???).
TBH I'm surprised more companies haven't got on board yet because an asphalt shingle roof will definitely NOT last the lifetime of the house, it is a wearable item just like tires or brakes on your car. I suspect within a few years the depreciation clause will be industry standard.
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