In inspecting my roof tiles (installed several years ago), I noticed that at the top of my rear roof where it meets the peak with the front of the house, there is a V shaped area where the top of the peak is missing a small flat tile. It looks like they should have cut an existing flat tile to fit the odd shape (probably about 8" across), but instead they just left it bare and instead rigged a peak tile to extent a bit over the area.
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