On first thoughts a living roof be it turf or sedum might seem to have less embodied energy than say a clay tile.
Green roof embodied energy.
There can be occasional surprises.
Concrete has a lower embodied energy but greater toxicity in its emissions.
Green roofs provide significant thermal insulation and shading for a building.
In australia the energy benefits of green roofs are most pronounced in their ability to reduce summer cooling demands.
By comparison a cool roof on this building will save about 700 btus per square foot per year.
Our one square foot patch of green roof will save about 1 000 btus per year in cooling energy which means that it will take about 40 years to recover the process embodied energy of the green roof.
The impact of a green roof on the roof temperature and heat flux is studied.
While this is lower than steel sheet products like concrete tiles clay tiles high mass per unit area comes into play so clay tiles will have a higher embodied energy per total roof area than sheet products.
Highlights a green roof thermal model was coupled to a building simulation code.
This value is equivalent to 6448 g c m 2 which is significantly greater than 378 g c m 2.
In addition additional maintenance and irrigation requirements should be considered especially with regard to green walls.
Their contribution to insulating and shading buildings can help significantly in reducing energy consumption and carbon pollution.
The effects of the leaf area index the roof insulation and the climate are discussed.
2009b study total embodied energy for the green roof components are 23 6 kg co 2 per square meter of green roof.
The main pollution issues with steel roofing are the dioxins produced during smelting and the pollutants produced in the manufacture of the usual pvc.
The next largest category of research is materials and resources.
Both sod roofs and lwa based lightweight aggregates roofs have been found to have a negative impact on the quality of their resulting runoff.
According to a usgbc report published in 2006 over 70 percent of the green building research is focused on energy and atmosphere research.
The potential energy savings of green roofs should be balanced against the added embodied energy required for their construction.
Some of the traditional ways of house building are extremely low in embodied energy.
Green roofs reduce building energy demand and improve thermal comfort.
Because they are fired they can have an embodied energy of around 6 5 mj kg university of bath uk see wikipedia on embodied energy.
Green building research is being done by national laboratories private companies universities and industry.
The embodied energy for green roof components are 23 6 kg m 2 5 pounds per square foot co 2 of green roof.
