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4 Drainage Systems to Install Artificial Grass on Commercial Rooftops

This article is helpful for condominium builders, designers, or those who are looking to create highly-trafficked recreational turf on a rooftop, deck, or balcony. Review 4 types of turf installation methods for commercial settings that provide superior drainage, and hear our professional opinion on the maintenance needs of each type of commercial rooftop turf system.

4 drainage systems used to install artificial grass on commercial rooftops

To hear how these systems hold up in pet-friendly areas, check out our article about installing pet turf over hard surfaces in commercial spaces

Drainage Needs for Fake Grass on Commercial Rooftops

Without superior drainage and ventilation, rainwater and other liquids have a higher probability of getting stuck under the surface of artificial grass. When liquids are trapped on hard surfaces mold and mildew may occur. For this reason, suppliers always recommend ensuring there is some sort of drainage grid for ventilation when fake grass is installed on rooftop decks.

This is especially important in commercial rooftop settings, where the surface is often much larger and collects higher volumes of liquids during rainfall and routine cleaning. Opting out of a drainage layer when installing artificial grass on a rooftop may cause a costly fix for your business in the near future. 

Air Drain System 

Air Drain's patented air void system is a time-tested way to help your synthetic grass drain water away from the rooftop quicker. Air Drain is a 1-inch-tall rigid material made from 100% post-industrial recycled content. It is designed to lift artificial grass to create an air void between the grass and the surface. This air void, in turn, allows rainwater and other liquids to flow through your artificial grass and off of the roof or balcony. 

Benefits of Air Drain:

  • Offers the Ability to Flush the Space of a Rooftop Turf Deck
  • 92% Air Void Space Allowing Waste Removal 
  • Replaces Other More Costly Methods (Trench Pipe and Gravel Drainage)
  • Provides Minimal Disturbance of the Existing Site
  • Quick & Easy Installation Process

air drain for drainage on commercial rooftop turf installation

Our Thoughts: 

This drainage system is what we see most often when turf is used on rooftops for both residential and commercial settings. The cost-effective and basic design has proven to be successful over time. This method works best when paired with artificial grass with permeable backing. As long as these two criteria are met, this system is often successful in accelerating drainage and providing air ventilation. Because this drainage grid is only 1 inch in height, this system works best on flat and level commercial rooftops that don't have utilities or other obstructions affecting the area where fake grass will be laid.

In comparison to other drainage options that are more expensive and require more site disturbance, Air Drain's rate of water flow is slightly slower. As you can see in the photo above, the spaces in the grid are fairly large and can sometimes be resistant to fully draining. Depending on the volume, liquids may get trapped in the gaps and drain at a slower rate.

Also, because the membrane has larger gaps there is a risk for puncturing and damaging the surface when someone wearing high heels walks on the grass. Depending on the intended use of the rooftop space, if you opt for Air Drain you may need to consider installing a hardscape for walking such as pavers or tiles in addition to fake grass. 

Artificial Grass Recycling

In conclusion, this method is excellent in residential and suitable for commercial applications. It provides an air void to allow rainwater to flow through without getting trapped on the surface for long periods of time. However, for commercial spaces, we often see more success with systems that provide quicker drainage and a more advanced design. 

Artificial Turf-Trays For Rooftops

Turf-Tray™ is an engineered tray system designed to build level and elevated decks with faux turf on pedestal systems. It's used in conjunction with adjustable pedestals and synthetic grass to provide a natural-looking lawn in unconventional areas. This allows commercial businesses to install artificial grass at an elevated height to hide any utility boxes, utility lines, and sloped surfaces. Because the pedestals build a raised surface, ventilation and accelerated drainage are more attainable than if the grass was just laying directly on the rooftop.

Tile Tech's Turf-Trays are separate grid-like pieces that join together, so this gives you tons of customization in regards to the size. They also specialize in pavers and wooden tiles, so you're able to create a multipurpose space with your own design! You can install the perfect space for your business's needs with ease.

Components Of Turf-Tray System: 

  • Artificial Turf Trays
  • Adjustable Pedestals For Leveling
  • Artificial Grass
  • Hex-Lock Disks
  • 1-1/4th Screws

Turf Trays for commercial rooftop artificial grass applications by TileTech

Turf-Trays Are Designed To Be: 

  • Lightweight: Turf Tray's materials make installation and transportation a piece of cake. This installation method is even more ideal for high rise buildings because materials can be quickly transported by elevator. 
  • Adjustable: The pedestal system provides the ability to build a level and raised surface that mimics the look and feel of a natural lawn on a commercial rooftop. 
  • Wear Resistant: Slip resistant in all finishings offered; also resistant to wear and tear.
  • Load Bearing: Very sturdy when used in conjunction with adjustable pedestals. Long-lasting with traditional fixing methods.

Our Thoughts:

One of the biggest benefits of this installation method for commercial rooftops is how easy it is to install. The process is just a few steps and does not require heavy lifting or the use of special professional tools. Because the surface is buildable, hauling the materials is simple as well. 

Because rooftops are by code designed with drainage in mind, there is usually enough of a natural slope on the surface to get rid of rainwater. Turf Trays are elevated and permeable, so they allow rainwater and other liquids to easily travel through the artificial grass and tray to the rooftop below before natural flowing off the roof. 

With the ability to elevate the surface there is added ventilation. However, the space between the trays and the roof's surface will be highly shaded. Pairing that with high temperatures and moisture creates the perfect breeding ground for bacteria. 

In conclusion, this turf installation method is quick and easy and it can be personalized to fit your business's needs. We think this is a great way to build a usable space on commercial rooftops for entertaining or casual recreation. It's also especially ideal when your space is uneven. However, this may not be the right choice for you if your rooftop and synthetic grass surface require consistent cleaning because the space between the trays and the roof will become nearly impossible to clean once the installation is complete. 



balcony turf cost calculator

Automatic Flushing System

Automatic flushing systems are most often used for pet turf, but can also be beneficial on highly trafficked commercial rooftops that are used for recreation or occasional pet use. In this scenario, there's a flushing system installed beneath the artificial grass that keeps rainwater and other liquids flowing into a drain. This system flushes the area periodically while keeping the surface of your fake grass dry. 

As an example, ForeverLawn's patented K9Grass Flushing System. This design provides a comfortable and natural-looking surface while including a hidden cleaning and drying system that makes it ideal for pet-friendly facilities, condos, and more. The flushing system provides effective drainage and adequate cleaning opportunities.

Automatic Rinsing System Components: 

  • Artificial Grass
  • Raised Air Grid
  • Naturally Sloped Impermeable Surface
  • Trench Pipe
  • Flushing System
        - Manual: Flushing port and hose connected manually and water run through each zone
        - Semi-Automated: Charged water line through pipes in each quadrant, controlled by              valve
       - Fully Automated: Charged water line connected directly to each quadrant                                powered by a sprinkler system
  • Pipes With Holes For Water Flow

K9 grass flushing system for pet turf on commercial rooftops

Our Thoughts: 

This system seems to provide the best cleansing and drainage results on a large scale. With the options for automation,  the entire space can be flushed and drained consistently ensuring that there is no bacteria build-up over time. This will also accelerate drainage even more. This method is most often used in pet-specific facilities due to its complexity but can be an excellent amenity in any commercial rooftop turf installation.

Gravel Filtration System

This drainage system is not as heavily practiced as the other drainage systems that we've reviewed. It is an alternative to the automatic flushing system, meaning its most ideal for spaces that require consistent cleaning and sanitizing such as pet turf or sports turf. This method will still require some type of drainage layer such as drain core, but may offer a solution for commercial businesses that are looking to install pet turf or turf for recreation on a rooftop. Since you can't simply flush urine and other waste from the rooftop, this natural filtration system will remove bacteria and purify the liquids before flushing down the drain. 

How It Works:  

Underneath the artificial turf will be a layer of drain core to help with ventilation and accelerate drainage. This drainage layer is very important when installing artificial grass on commercial rooftops. Then there will be two layers of gravel. Larger pieces of rock at the very bottom and smaller more compact pieces of gravel on the top layer. These two layers of gravel are separated by a layer of cloth. The top layer is typically mixed with some type of chlorine-infilled turf deodorizer for the best results. The top layer of loose gravel will act as a filter only allowing clean liquids to filter through and drain into the bottom layer. 

Gravel filter K9 Pet turf system

Our Thoughts: 

If you want to install pet or sports turf on your rooftop or deck, we think this as a viable option. Gravel filtration can filter out waste and bacteria from urine and sweat, ensuring that there's none flushing down below. However, it is difficult to know what this system entails because not enough research has been done on its long-term effects and maintenance needs.

Thank you for reading this article on how to build a commercial rooftop space with artificial grass. We hope it was helpful in your designing process, while we work with some of these systems daily our findings our from our experience only. If you're interested in partnering with InstallArtificial, let's talk! Request a custom estimate below. We'll be waiting to discuss your project in more detail.


* Commercial facilities are all unique. Factors such as size, ceiling height, HVAC components, airflow patterns, windows, and use can be different. Always consult with a professional that is specifically familiar with these requirements before making any changes. We cannot guarantee the safety of your drainage system; always consult a professional before making any changes of your own. *