Telegraph: Thatchers say milder, moist winters with less sunshine are leading to the colonisation of roofs by algae and mosses which may, in some conditions, reduce the life expectancy of the thatch. At the same time the wet summers mean the straw used to make the roofing is in increasingly short supply and could be prohibitively expensive. Marjorie Sanders, head of the National Society of Master Thatchers said existing thatched roofs would suffer badly in the expected warm, mild climate …