Green Roof Insulation

Used over a whole roof a green roof will be the single overriding design influence on the house as well as impacting on the construction right down to the foundations.

Green roof insulation. The degree of sound insulation will depend on the thickness of the green roof structure. For some people it s green when it contains a high percentage of recycled materials. Green roofs reduce sound resonance by 3 db and provide sound insulation of up to 8 db. With a high capacity for water retention the green roof reduces the volume and runoff flow into stormwater sewer systems.

Thermal insulation in some cases a green roof may include thermal insulation typically a layer of extruded polystyrene. It is available in 40 psi 60 psi and 100 psi compressive strengths so it will not crush during construction or under load after placement of the vegetated cover. The rigid insulation material is typically extruded polystyrene xps which is resistant to moisture absorption and has been used in green roof applications for decades. For others it s when it doesn t contain harmful substances that can cause health problems.

What is the r value of a green roof the most common request i get from architects and engineers is for the r value of a green roof system. In addition to transforming co2 into oxygen the plant cover filters atmospheric pollutants in the form of particles deposited on foliage and growing medium. Green roofs provide water retention green space and improved water and air quality while reducing energy consumption. Green roofs not only help reduce the urban heat island effect by covering conventional dark roofing surfaces with vegetation which absorbs less heat but they also use solar radiation to evaporate water from the growing media and transpire the absorption of water through a plants roots and release of it through its leaves as a vapor moisture from the plants.

In order to make sure we are all clear on how insulation works particularly in a green roof system we need to take a little journey through the lexicon of insulation terminology starting with. Both roof vegetation and soil increase roof insulation reducing ambient air temperatures and building energy consumption. 10m surface covered with grasses can eliminate 2kg of suspended particles from the air each year. Technically speaking home insulation is green by its very nature because it saves energy.

This may not seem much but for the human ear an 10 db reduction in noise levels is 50 quieter. While this can be positioned below the roof deck installation above the waterproofing known as an inverted green roof is preferred as it further protects the membrane from condensation and physical damage. A green roof is in ecological terms a great and simple thing to do. A 15 000 square foot liveroof green roof on the newly opened korematsu middle school is reducing the school s environmental footprint providing a living model of sustainability best practices reducing energy costs and improving air quality.