One of the main problems affecting these Croydon roofs is (spalling tiles) basically flaking tiles caused by the freezing of rain water or snow that has found its way between the gaps on the plain tile courses and settling behind the tile and with the constant freezing and expansion over the winter period this can cause serious roof damage over the years.
Certain roof tile manufacturers tiles from back then suffer more then others and in some cases quite extensive Damage to 100% of the tiles on the roof may take place. It is very hard to tell how extensive this may be as the spalling of the tile generally occurs to the back of the tile where it laps the tile on the lower course making it difficult to spot by roof inspection or from within the roof void. Our usual procedure when advising on when to go for roof repairs or a new roof is to inspect the roof with a pair of binoculars looking at the bottom edge of the tiles if there appears to be hairline cracks there it’s more then likely there is spalling to the back of the tile.
Any spalling roof will only get worse with every harsh winter and in the long term re-roofing would be the best option as replacing the roof tiles here and there where required will only be a stop-gap measure.
I will cover problems affecting roof tile ridges, lead flashings and guttering on Croydon’s roofs in a later article.