SpecTips: Achieving Sustainability Credits with Roof Garden Systems
Over the last several years, the architectural community has ramped up its focus on sustainable products and systems to help reduce the environmental impact of new building designs. And although there are many products and systems that can help you meet green building standards, some products come with tradeoffs – including sacrificing the system's long-term performance for a product that is more eco-friendly to produce. When choosing building products and systems, it is important to take a holistic approach and consider all aspects of sustainability, including the manufacturing process, long-term performance, environmental benefits, energy savings, and resiliency. In the roofing industry, there is no system that checks all the sustainability boxes better than a Roof Garden.
Roof Gardens, or vegetated roof systems, are recognized by green building standards such as LEED®, Living Building Challenge™ (LBC), and Green Globes® (GG) as multi-attribute building product systems. This means the system can serve multiple sustainable purposes through its use, such as stormwater management, reducing the Heat Island Effect, and providing access to nature within the building's footprint. This diverse set of attributes also means Roof Gardens can achieve multiple credits, in multiple credit categories, in programs such as LEED, LBC, and GG.
Rainwater Management (Stormwater Management) – Roof Gardens retain and detain stormwater through moisture retention fabrics, water holding reservoirs, growth media, and vegetation. Meeting or exceeding the required levels of stormwater/rainwater retention is accomplished though calculations for your specific building project. Verifying the roof assembly design meets these water holding capacities before specifying the assembly is important. You may need to increase water holding capacity by adding layers of retention fabric or adjusting media depth based on your specific project's needs.
Heat Island Reduction – Roof Gardens help to reduce the urban heat island effect through the vegetation's natural evapotransporative cooling. Achieving the Heat Island Reduction credit is based on covering a certain percentage of the roof with vegetative or reflective roofing material. Verify your project design is meeting these requirements.
Direct Exterior Access – Roof Gardens and paver systems add valuable, useable space to an otherwise forgotten area of a building. Providing building occupants with access to this space allows them to interact with nature, which is especially important in urban environments. Verify your square footage meets the minimum required for the credit.
These are only a few of the credits that Roof Gardens can help your project to achieve. By specifying a Roof Garden for your next project, you can meet or add more credits to your sustainable building design. Adding a multi-attribute product to your building design can improve your bottom line while also helping you meet the sustainability goals for your project.
TIPS
Note: It is always a good idea to review the Division 1 sections pertaining to the requirements of the green building standard you are specifying for your project before adding any information or requirements in individual specification sections.
- Modify the Division 1 section for Sustainable Design Requirements per your building project. This narrows down and clarifies which green building certification standard you are using, what informational submittals are required, and general expectations for the project.
- Specification Section 077273 “Vegetated Roof System” – Part 2 – Products – Add any water holding capacity requirements that were determined in the stormwater calculation for the design of the project.
- Specification Division 7 Roof Assembly – Part 2 – Products – Add any Solar Reflectance Index (SRI) numbers necessary for the exposed portions (those portions of the roof which are not covered by vegetated roofs) to meet the project requirements for reflective roofs.
- Specification Section 077273 “Vegetated Roof System” – Part 2 – Products – Add any walkways or planters required for your building design and specify these in the product section.
For information on how Carlisle Roof Garden products contribute to meeting green building standards, check out Carlisle's Sustainability Brochure.
For more information on Carlisle's Roof Garden products, visit the Roof Garden page on Carlisle's website.
Roof Gardens, or vegetated roof systems, are recognized by green building standards such as LEED®, Living Building Challenge™ (LBC), and Green Globes® (GG) as multi-attribute building product systems. This means the system can serve multiple sustainable purposes through its use, such as stormwater management, reducing the Heat Island Effect, and providing access to nature within the building's footprint. This diverse set of attributes also means Roof Gardens can achieve multiple credits, in multiple credit categories, in programs such as LEED, LBC, and GG.
Rainwater Management (Stormwater Management) – Roof Gardens retain and detain stormwater through moisture retention fabrics, water holding reservoirs, growth media, and vegetation. Meeting or exceeding the required levels of stormwater/rainwater retention is accomplished though calculations for your specific building project. Verifying the roof assembly design meets these water holding capacities before specifying the assembly is important. You may need to increase water holding capacity by adding layers of retention fabric or adjusting media depth based on your specific project's needs.
Heat Island Reduction – Roof Gardens help to reduce the urban heat island effect through the vegetation's natural evapotransporative cooling. Achieving the Heat Island Reduction credit is based on covering a certain percentage of the roof with vegetative or reflective roofing material. Verify your project design is meeting these requirements.
Direct Exterior Access – Roof Gardens and paver systems add valuable, useable space to an otherwise forgotten area of a building. Providing building occupants with access to this space allows them to interact with nature, which is especially important in urban environments. Verify your square footage meets the minimum required for the credit.
These are only a few of the credits that Roof Gardens can help your project to achieve. By specifying a Roof Garden for your next project, you can meet or add more credits to your sustainable building design. Adding a multi-attribute product to your building design can improve your bottom line while also helping you meet the sustainability goals for your project.
TIPS
Note: It is always a good idea to review the Division 1 sections pertaining to the requirements of the green building standard you are specifying for your project before adding any information or requirements in individual specification sections.
- Modify the Division 1 section for Sustainable Design Requirements per your building project. This narrows down and clarifies which green building certification standard you are using, what informational submittals are required, and general expectations for the project.
- Specification Section 077273 “Vegetated Roof System” – Part 2 – Products – Add any water holding capacity requirements that were determined in the stormwater calculation for the design of the project.
- Specification Division 7 Roof Assembly – Part 2 – Products – Add any Solar Reflectance Index (SRI) numbers necessary for the exposed portions (those portions of the roof which are not covered by vegetated roofs) to meet the project requirements for reflective roofs.
- Specification Section 077273 “Vegetated Roof System” – Part 2 – Products – Add any walkways or planters required for your building design and specify these in the product section.
For information on how Carlisle Roof Garden products contribute to meeting green building standards, check out Carlisle's Sustainability Brochure.
For more information on Carlisle's Roof Garden products, visit the Roof Garden page on Carlisle's website.
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