The book starts by setting out the duties of a building pathologist in the context of the modern roofing industry, defining failure and explaining its underlying causes. The main chapters then deal with the main specific types of failure: fire, shrinkage and roofing systems displacement, calendar shrinkage, foam insulation shrinkage and 'stretched' membranes, plasticizer migration, bitumen incompatibility, built-up roofing felt porosity, blistering, thermal insulation instability, foam insulation problems, torch applications, polymer dispersion, asphalt-glass fibre shingle splitting, lack of appropriate venting, problems with cool roofing and problems with organic fibre-portland cement shingles. The book concludes with an outline of the principal rules for long service life roofing.