
In reality, flat roofing is not entirely flat. There is always a slight slope towards the drain. Gravity allows the drainage system to work, so the water needs to have a natural flow away from the roof. Despite this, common drainage problems can occur associated with flat roofing.
Types of Drains for Flat Roofing
- Foundation problems
- Infiltration of water into living spaces
- Water damage to walls and casings
These problems may be common, but there are still numerous advantages to having flat roofing and each type of drain system has its own pros and cons.
Inner drains
These sit away from the edge towards the center of the roof. A pipe system below the drain that shuttles the water away. Often these can form pools of water on the surface if there are any clogs to the system and the heavy water can eventually find a way into the building. These are also more expensive and repairs can be costly but they are great for colder climates as the pipes do not freeze.
Scuppers
These are small boxed drains that exit through the parapet wall. The slight slope of the roof allows water and debris to move along the roof and out the scupper. These too can become clogged and if water pools near the roof edge and if they are not connected to a downspout, then water can damage your foundation as it falls. These drains are not very expensive and are easier to maintain and prevent clogging.
Gutters
These metal structures sit along the edge of the roof, collecting water as it flows down the slope. This help protects your foundation and helps to control the flow of water away from the roof. They are inexpensive and are the best way to protect your foundation, basement, and soils from erosion.
Final Thoughts
Flat roofing is a great choice for any building, just be sure you have the appropriate drainage system in place too. There are pros and cons for each choice so be sure to discuss all options with an experienced roofer. Call us today and we will help you decide which drainage system is best for your needs and your commercial flat roof.