Flat roofs are a fairly common roofing choice for commercial constructions. Flat roofs are relatively inexpensive making them an ideal choice for building owners. On top of improving the aesthetic appeal of many building designs, flat roofs are actually quite durable and resistant to environmental factors that lead to roof damage such as hail and wind. Flat roofs also give ample space for solar panels, air conditioning units, and even rooftop gardens.
The one challenge of having a flat roof is drainage. Slanted roofs allow water to drain automatically but in the case of a flat roof, a built-in drainage system must be put in place to help with moisture and debris removal. Failure to ensure proper drainage in flat roofs may lead to leaks and even structural damage to the building.
Why Proper Drainage for Flat Roofs is Important
Poor drainage on flat roofs leads to the following problems:
- When water pools on the roof, it causes leaks that can lead to structural damage
- Extra stress on the building from ice during winter.
- Debris such as twigs and leaves may accumulate
- Damage to the caulking and tar due to the water pooling and debris build-up
- Leaks may even occur near roof features such as chimneys and vent pipes.
Below are drainage alternatives for flat roofs:
This type of drainage works in a similar manner as the drain in your shower or sink. The drains are installed on the roof where most water is collected. The water is led into a system of pipes installed below the roof. The liquid then travels through these pipes and is dispensed into a gutter or downspouts away from the side of the building.
Interior drains have the following advantages:
- This drainage option includes a strainer that keeps debris from clogging the pipes.
- This drainage structure cannot be seen from the street making the building aesthetically pleasing
- Inner drains are protected by the buildings and walls and so won’t freeze or crack during winter.
Interior drains have their disadvantages. They are a very expensive system to install and while they are not easily susceptible to damage, any damage that occurs will require you to call an expert.
This is a choice for many houses and commercial buildings. Gutters catch water as it rolls off the edge of the roof and diverts it into a downspout which in turn safely dispenses it away from the building’s foundation.
Gutters are the most affordable drainage solution for flat roofs. Gutters direct runoff away from windows and doors. People approaching your building in bad weather will not be inundated by water coming from your roof.
Many builders will, however, avoid installing gutters due to several potential problems:
- They are continually exposed to the elements and they may become clogged with debris such as leaves and twigs. Clogged gutters hold water that freezes and causes cracking.
- Water and debris may be so heavy that it causes the gutters to tear away from the building. This may result in damage to your roof.
These are perhaps the most effective solution for flat roofs. This is a drainage system that involves large square openings along the edge of the roof. These shoot water away from the side of the building. It is common to install downspouts directly below these openings to collect the water and drain it away from the building.
Scuppers offer a budget-friendly option for roof drainage. Scuppers are also easy to maintain and rarely get clogged with debris. They may even enhance the aesthetic appeal of your home or building.
Scuppers have several disadvantages:
- They are not an ideal choice for dealing with water from melting ice or snow.
- They are less effective on a flat roof with little to no pitch to enable water to flow to the edges.[contact-form][contact-field label=”Name” type=”name” required=”true” /][contact-field label=”Email” type=”email” required=”true” /][contact-field label=”Website” type=”url” /][contact-field label=”Message” type=”textarea” /][/contact-form]
High Performance Restoration LLC
6500 Preston Rd #201
Frisco, TX 75034