Nowadays, people regard sloping roof space as living space, and the insulation of sloping roof becomes more and more important. Sloping roof insulation technology usually lay rigid polyurethane foam board above the rafter to block the thermal bridge, and improve the air permeability and sound insulation effect of the roof structure at the same time. At present, the insulation measures of sloping roof have not been carried out in China. The main purpose of changing flat roof to sloping roof in most cities is to solve the problem of beauty, and then it has a certain heat insulation effect.