Roof Drains Design

The average flat roof does not have an optimized draining system.

Roof drains design.

The roof is sloped towards the drain through either tapered insulation or through joist modifications below the roofline. Roof drains from zurn include combination primary overflow control flow dual outlet siphonic retrofit and more which cater from educational to commercial needs. We also stock many of the top selling drains and parts onsite so most orders ship same day. Inner roof drains are used on flat roofs and include a low section or channel that collects water and feeds it into a concealed drain that leads to an underground drainage system.

If you need help finding a drain ask our drain wizard or call to speak with our roof drain expert. 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. Take the roof s total square footage and divide by the total square footage handled by one 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.

Determining the exact roof area and the number of drains is precise work so it requires coordination with the building s architect. You also must include half of the area of any vertical walls that may divert rain to the roof. This form of roof drainage is preferred if a clean exterior appearance is desired. Inner drains are resistant to freezing but can require careful maintenance to prevent problems.

So often we find that inner drains are high on the roof causing water to pool around them. 50 000 4 400 11 36. In many instances though not necessarily always you will want the gutter and downpipe sizes to be the same for all gutters and downpipes on the project. These drains are distinguished by having higher rims.

The main benefit of inner drains is that the system is hidden from view. Most of the time there is not a positive pitch to let water drain and that causes ponding. The positioning design and installation of a drainage system are one of the most important factors to have a relatively low maintenance roof. The result is the number of drains needed.

There are three types of drain systems on a flat roof. Design approach for a given roof configuration the first task is to decide on the number and location of downpipes as this will determine the size of the effective roof areas. Smith carefully designs and manufactures a full line of roof drains deck drains scupper drains promenade and parking area drains and more to satisfy both the artistic eye of the architect and the calculating mind of the engineer. Most draining systems on flat roofs have a poor design or are not correctly installed.