I just did a home inspection on a home 80+ years old. The roof looked great. I had Slate roof tiles of different ages, meaning it has had the opportunity of maintenance in the past. Unlike asphalt, or composite, roof shingles, slate tile roofs are something you have to check yearly. You might loose a tile, or two, so keep an eye out for need to call your local qualified roofer.
I tell my clients, as they drive up, or mow their lawn, just take a quick look at the slate roof tiles. A missing tile will sometimes stand out like a smile from a child missing a baby tooth or two.
So good luck with those great slate roofs, and remember your slate roof tiles do need to be maintained over life. Unlike asphalt shingles, which usually need complete replacement every decade or two, or three if you have some good shingles and mild weather.
later,
Pa Home Inspector
