My roof has concrete interlocking tiles. Recently I found on the roof on top of the partly protruded ground floor, the right corner of one of the tiles is broken off, leaving a small gap at the interlock between two adjacent tiles. The tile may be broken for a long time as I cannot see any missing pieces around. The breakage looks quite long and I don't know if it is more than the headlap distance of the tile beneath it. From inside the house there is no sign of leaking. To determine if it is worthwhile to call in a roofer and just have this single tile replaced, I wonder how I can tell if water has get into the gap and onto the underlay (felt)? If it does, would rain just run down the felt and drip into the gutter or somewhere between the gutter and fascia board?
Many thanks.
Many thanks.