GREEN ROOF TYPES
ALL UNDER ONE TENT
First and only Green Roof tent in the world! Created 2003 international garden show, Rostock, Germany. Picture: Stephan Arnold, Green Roof Technology
Green Roof Types
Types of Green Roofs explained:
It's common knowledge that, unlike trees which need ample space for their roots, mosses require very little. In addition to mosses and trees, there are countless other plants, each with varying root space needs to thrive. While a tall shrub may start to grow in a shallow layered cultivation medium, it probably won’t last more than a few years and never as long as the building structure underneath.
The true Green Roof professional classifies green roof types not just by their overall thickness, but also considers more complex factors such as material and aggregate porosity, distribution of granular size, potential total weight per area, organic content, technical life-supporting systems, and expected maintenance of the vegetation.
Meanwhile, Green Roofs are categorized into three (3) distinct types and the transitions between these types can be seamless within one area.
Ultimately, the specific plant community intended for a Green Roof will dictate the type of Green Roof:
| Extensive Green Roof | Semi-Intensive Green Roof | Intensive Green Roof |
| • Less rooting space
• Mosses to Perennial low growing • Low organic content • no irrigation system • Low maintenance expectations • 3”-6” (7cm- 15cm) deep |
• Increased rooting space
• Perennials and small shrubs • Increase organic content • seasonal irrigation optional • Some maintenance • 5”-8” (12cm- 20cm) deep |
• Maximum rooting space
• All plants and trees possible • Sufficient organic content • Smart irrigation systems • Regular maintenance often weekly • 8”-36+” (20cm- 100+cm)
|
Seamless Transition Among Green Roofs Types
Picture from Green Roof Brochure in 1982
Only 4" (10 cm) overall depth but still an Intensive Green Roof because the Putting Green requires daily maintenance and is connected to a life-supporting system (automatic Spoon-Feeding).
Three Green Roof Types - History
The three (3) main types of Green Roofs can be traced back to the German FLL-Guideline in the early 1980's for Green Roofs.
In the late 1990s, Jörg Breuning introduced these categories to the Anglo-American professional community, like Green Roof for Healthy Cities and ASTM as a support to get them started in the Green Roof industry. Additionally, Jörg was responsible for the initial translations into English, which had been the trigger that these categories are now recognized globally.
Of course, the FLL-Guideline serves as the foundational document and model for all Green Roof guidelines and standards worldwide, being the most comprehensive resource available until today.
Fun fact: Rather than utilizing this invaluable document, some organizations in the USA chose to reinvent the wheel, leading to approximately five different versions from various associations in the Green Roof field as of 2024. This approach didn't benefit the industry as a whole and seems to cater more to certain individuals' egos or corporations. 😉
The power of Leak Detection Systems is still underestimated in North America and could save the clients thousands.
Line between Green Roofs
The three Types of Green Roofs (Extensive, Semi-Intensive, Intensive) can have many subcategories and it is called Green Roof Taxonomy or Taxonomic Classification. The most common subcategories are:
Green Roof Taxonomy
Military facilities Green Roofs for over 200 years because of many strategic benefits and to extend the lifespan of the roof. Living camouflage is the best protection for military assests inside the structure.
Line between Green Roofs
All Green Roof Types On One Roof With Monolithic Platform System
Seamless transition without roof penetration and maximum use of roof. This is a payback on the first day for the building owner and the environment.
©️ System solution and picture by Green Roof Technology and Klima Roof
Green Roof Technology crafts lit·er·al·ly endless varieties and combinations of vegetated covers from 0° - 90° slope.
Any seamless combination of different Green Roof types is possible. The limit is the sky.
We're here to assist!
Seamless types of Green Roofs encompass everything a roof structure can support. This can includes amenity decks or areas with planters and landscaped gardens. Additionally, it can involve the integration of technical roof equipment, railings, and safety features. Furthermore, there are smart roof drains, Blue Green Roof technology, and renewable energy options, like solar panels or micro wind turbines. Ultimately, we combine all these elements together - seamless.
Line between Green Roofs
Intended Plant Community
For instance, if a professional chooses a specific plant selection for a Green Roof, it is called an intended or desired plant community. However, such a plant community is only a snap shot of this moment.
Because we all know that plants grow, that other plants come in (e.g. airborne seeds), and that some plants get replaced, the Green Roof undergoes changes. As horticulturalists, we know that nature or any plant community lives through natural succession.
Green Roof maintenance can manage the general timeline for natural succession, but it cannot stop nature by doing her thing. In other words, there is a chance that the type of Green Roof will alter. Especially, the increase of extreme weather patterns requires new the means and measures for managing natural succession continuously. For that reason, crafting Green Roofs for over 40 years is an advantage.
With respect of Climate Change; data from existing Green Roofs research will get obsolete soon. Our tailored Green Roof solutions are prepared for the uncertain future and for existing Green Roofs we have smart solutions to adjust without replacement. In other words: We have common (horticultural) sense.
Green Roof Research
Moreover, Green Roof Technology massively supported Green Roof research in different countries over the last three 3 decades. Therefore, in most research we criticized the lack of common sense, considerations for Climate Change, and not using standardized materials or methods. However, all research came to almost the same results in their snapshots. Basically, all Green Roof benefits are confirmed endlessly.
Based on the environmental challanges the next generations will face, it is now time investing research funds into massive Green Roof installations of all types. The time of sitting in a climate controlled laboratory is over! The industry needs hands-on people who do the hard work at any weather for the installation of Green Roofs. Especially in North America, means and methods of Green Roof installation techniques lack far behind most European countries. In short, combat Climate Change by doing and not by researching. We do have all the data we need.
For example Solar Garden Roofs and Blue Green Roofs are Green Roof types that are future oriented. They increase sustainability, resilience and Return of Investment when fully integrated with one or more Green Roof types.
