roof rainwater catchment systems
Roof Rainwater Drainage System
Roof Rainwater Utilization
rainwater fallen on the roof
Changing flat roof to slope roof
diagonal ridge for hip roof，vertical ridge for gable roof
flat- roof-to- slope-roof
flat-roof-to-slope-roof
flat-roof-to-sloping roof
roof pressure roof weight
roof prism (=roof-angle prism)
10104 m3 floating roof tank