Brown Roof System

Brown or biodiverse roof systems tend to be lighter and require less maintenance, care, and irrigation than other green roof systems. The system is usually specified on roof slopes of up to 35°, however, with careful design consideration, pitches above 35° can be achieved. This allows for greater freedom of design and can help support plans for urban greening in towns.

Brown or biodiverse roof systems offer a wonderful opportunity to recycle the excavated material from the construction site, and one that is often a criterion of the build. Care should be taken that this material is of appropriate quality to ensure water retention and suitability of medium growth to attract and support the local fauna and flora naturally. Brown or biodiverse roof systems make use of green roof substrates with higher organic content (minimum of 20%) to ensure that the specified wildflower plugs, or seeds, can flourish.

What are the benefits of brown/biodiverse roofs?

• Aiding biodiversity by creating additional habitat for flora and fauna that is specific to the area and attracts wildlife and pollinators
• Relatively lightweight due to application of a shallow substrate at varied depth (up to 150mm)
• Improving the sustainable drainage capacity of the roof
• The acoustic performance can be enhanced through the noise reduction the system can achieve
• Reduction of heat island effect and improvement to air quality, especially in urban areas with a higher concentration of dust particles and gas pollutants
• Heat insulation and protection for solar gain presents a potential for energy savings
• The lifespan of the roof membrane is extended through protection from climatic changes and UV irradiation
• Aesthetics of the building can be improved, and brown/biodiverse roof systems can serve as a positive selling point

Considerations for installation of brown/biodiverse roofs?

• Maintenance requirements should be considered as brown/biodiverse roof systems do not allow for roof access
• Any elements that may have sharp edges or points could damage the waterproofing membrane and must be avoided
• Regulatory requirements
• Wind uplift and weight loading
• Irrigation requirements must be considered

IKO products are manufactured in the UK from responsibly, and where possible, locally sourced materials in order to reduce our carbon footprint and help with the sustainability of your project. The majority of our roofing systems are also BBA certified.