| 摘要 |
A bi-functional roof drain includes a housing forming a drain manifold and a primary drain outlet to connect to a primary drainage system. A backup drain pipe penetrates the housing and extends through the manifold. The top of the backup drain pipe is positioned a distance above the housing, which may be variable. With this drain a method of retrofitting a roof drainage system to provide primary and backup water drainage is also presented. This method includes removing an existing uni-functional roof drain from a deck penetration through the roof, and installing a bi-functional roof drain in the same deck penetration. The two drain outlets are connected to the primary and backup drainage system. The height of a top opening of a backup drain pipe of the bi-functional roof drain may be adjustable in relation to a surface of the roof. |
