I have no experience with how this relates to P&C insurance, but in my experience “shake” roofs are made with wood shingles and would have considerably higher risk of fire than a metal or tile or slate roof or one made with composite shingles.
Parts of California (maybe the whole state?) have outlawed shake roofs due to the risk of fire. They were popular in the late 1980s to mid 1990s as they were perceived as being more attractive than composite roofs. They fell out of favor when the higher risk of fire became apparent. I think some HOAs still require shake roofs though.
That said, I’m sure some are safer than others. I think cedar is less likely to ignite than other types of wood, for example. So that might be where your “Class A” comes in. It seems very unlikely to me that there exists a shake roof with the same fire risk as composite or other materials … unless it’s somehow a fake wood.
Ceder is actually really easy to ignite, as wood goes, but otherwise i agree with everything twig says. (Ceder is a good wood for construction because it is inherently resistant to rotting, but it’s anything but fire retardant.)
When i was house hunting, i looked at a house with a wood shake roof, and ended up buying one with asphalt shingles. I’ve since replaced it with aluminum shingles. The realtor told me that wood shake was “higher quality” than asphalt shingles, but as best as i could tell they didn’t last as long, and were more expensive to replace, so it seemed like a negative to me, even living in a place where wild fires aren’t a thing.
Huh, I must be thinking of a different kind of wood then.
My former in-laws had a shake roof and basically every summer my FIL & then-husband were up on the roof replacing a portion of shingles. I think they basically replaced 1/x of the shingles every year where x is the life of the shingle. And while I can’t recall for certain what x was, I recall being shocked at how low it was. I want to say 5 or 6. This was in an especially rainy part of the country. I think they last longer in other climates, but they still have a short life.
They burned the old shakes in a wood stove which was a material portion of their total heat for the house, but still… the whole thing made me want to never ever own a house with a shake roof.