Primary Roof Drains And Roof Area Drains

Pitched roofs not surrounded by parapet walls are generally drained by gutters.

Primary roof drains and roof area drains.

An additional roof drain should be added for each 10 000 square foot area. As we will see in steps 3 4 the size of the roof drain lines is dependent on the square feet of the roof area being served by each roof drain. These will drain to somewhere near the center of the roof and down through the building to underground storm mains or a detention pond. A secondary roof drain achieves its function by controlling the water build up.

Therefore the bottom most recessed roof received the drainage from all upper roof areas. A good rule to follow is to provide two roof drains for a total roof area less than 10 000 square feet. Zurn offers a full line of combination primary overflow roof drains. Roof drains are generally installed on flat roofs or roofs surrounded by parapet walls.

The drains should be placed at a maximum of 75 feet in each direction away from each other. Drainage for each roof consisted of two pairs of primary and secondary drains. Siphonic primary roof drains. Siphonic combo primary overflow drain.

How far should a primary roof drain be located from the secondary drain. Siphonic roofdrain with debris guard. A typical commercial or multifamily residential building will utilize one of the following types of primary roof drainage. This form of roof drainage is preferred if a clean exterior appearance is desired.

Drainage for roofs cascaded down from upper to immediately lower roofs. Discover where to buy. Paramount to eliminating the threat of roof collapse due to water accumulation is the installation of roof drains or gutters. Because of that no certain distance exists.

A standpipe or dam built within the secondary drain dictates the anticipated water depth. Roof drains from zurn include combination primary overflow control flow dual outlet siphonic retrofit and more which cater from educational to commercial needs. These drains are distinguished by having higher rims. In addition to the primary roof drains there will also be overflow drains which are used for redundancy and sized in the same manner.

All roofs shall discharge to a storm sewer or drain to daylight at grade at a safe location approved by the building official.