When you’re managing a commercial building, you’ve got enough on your plate already—operations, tenants, maintenance schedules. The last thing you need? Water pooling on your flat roofing, slowly turning into a budget-breaking problem.
Unlike traditional pitched roofs, like shingle and metal roofs, flat roofs do not have much slope, which causes water to pool on the roof surface during the rainy season. Water pooling on the roof structure for long periods leads to various problems, such as roof leaks, plant growth, and further damage to the building’s structure.
A solid commercial roof is about more than just multiple layers of roofing membrane and insulation—it’s about protecting your people, your property, and your bottom line. And smart drainage is key to keeping that roof doing its job. There are three types of flat roof drainage systems available for your commercial flat roof in Plano, TX. Below, Triumph Roofing looks closely at all three to help you discover the best drainage system for your property.
Drainage Options for Your Flat Roof System
Here are the three most common types of drainage for commercial flat roofing systems:
1. Internal Drains
Internal drains are a common drainage system in most commercial buildings. The drainage pipes are placed under the roof and in the walls of the building. They are often positioned towards the center of the roof or the place where the slope of the roof allows water to collect.
Appropriate for large low slope roofs and flat roofing, internal drains help in draining the water away from the building. The internal drain system usually features a strainer to catch debris and avoid pipe blockages.
Why Internal Drains Are a Great Option for Your Building:
- Protected From the Elements: Since the drain pipes are internal, they’re less likely to freeze or clog due to outside debris.
- Engineered Drainage: Multiple drains can be placed to handle large volumes of water and reduce stress on the membrane or flat roofing materials.
- No Interference With Aesthetics or Traffic: They’re great for buildings where exterior visuals or rooftop equipment placement matters due to foot traffic or solar panels.
Interior drains are super effective as long as they stay clear. Regular inspections and debris screens are essential—clogged interior drains can lead to standing water or hidden leaks inside your building.
2. Scuppers
If your building has parapet walls (those raised edges around the roofline), you’ve got a perfect setup for scuppers. A scupper is an opening in the sides of the walls that allows excess water to drain from the flat roofing material on commercial buildings. It carries excess water from the roof into the gutters or downspouts through conductor heads.
Scuppers can be combined with gutters and downspouts to direct the water flow in the desired direction. If you’re not using gutters or conductor heads to collect water, make sure that the scupper spouts extend past the exterior walls of the building so that the water does not drip along the building.
Why Scuppers Are a Smart Choice:
- Budget-Friendly: Fewer moving parts make for a more affordable install and easier long-term upkeep.
- Great for Mid-Sized Commercial Roofs: Scuppers are often ideal for flat or built-up roof systems in moderate climates with good natural drainage on the property.
- Visible Performance: If there’s a blockage, you’ll see water backing up on the flat roof surface—no hidden surprises.
When it’s cold outside, scuppers and downspouts can freeze up, causing overflow or backup. That’s why it’s important to inspect them seasonally and install heat tracing if needed.
3. Gutters
A gutter, also known as a conductor pipe, is a shallow trough that is placed beneath the edge of the roof to carry excess water away from the building. Water runs toward the edges of the roof (yep, even flat roofs are slightly sloped) and enters a gutter system mounted along the perimeter. Downspouts carry water safely away from the foundation.
Why Gutters Are an Ideal Drainage Solution:
- Simple to Install and Maintain: If your roof design allows it, gutters are a straightforward, tried-and-true option.
- Easy to Access: Cleaning and inspection are a breeze—especially helpful for facility teams managing multiple properties.
- Customizable Layout: Gutters can be tailored to unique building shapes or roofing obstacles.
The maintenance and durability of gutters depend on the materials used. The most common materials used to make gutters are aluminum, vinyl, and galvanized steel. To ensure gutters work properly, they must be regularly cleared of debris.
Choosing the Right Solution for Your Flat Roofing System
There’s no cookie-cutter solution when it comes to commercial flat roofing drainage. The best system depends on:
- Roof Size & Design: More square footage = more water to move. Large buildings often need interior drains or hybrid systems.
- Climate: Frequent freeze-thaw cycles? Your drainage solution will also need insulation and pipe protection.
- Building Use: Are there sensitive operations below? Extra protection might be worth the investment.
- Maintenance Resources: Got an in-house crew? We can set you up for easy upkeep. Outsourcing it? We can help with flat roof maintenance services.
At Triumph Roofing, we take the time to walk your roof, assess your unique setup, and recommend a drainage plan that makes sense—not just for today but for the long haul.
Why Drainage Isn’t Just a “Set It and Forget It” Situation
Here’s the deal—poor drainage leads to ponding water. Ponding water leads to accelerated wear on your roofing material, leaks, and even structural issues. Suddenly, that “out of sight, out of mind” flat roof is costing you thousands in unexpected repairs.
That’s why we treat drainage as a core part of any flat roofing project, whether it’s a new install, a retrofit, or a repair. With the right system in place (and a solid maintenance plan to back it up), you can expect:
- Extended roof lifespan
- Fewer emergency repairs
- Improved energy efficiency
- Peace of mind during every storm
Let’s Design a Roof That Works as Hard as You Do
These are the three different drain systems you can use in Plano, TX, flat roofing systems to avoid water pooling and its repercussions. Each draining system has its own pros and cons that you ought to discuss with your commercial roofing company. The suitability of any type for your building depends on your roofing system, surroundings, and various other factors.
Find the best drainage solution to protect your flat roofing with the commercial roofing contractors at Triumph Roofing. We are a leading commercial roofer in Plano with extensive experience in new flat roof installation, maintenance, and repairs. To discuss your requirements, give us a call or fill out our contact form and our team will get back to you as soon as possible.
