First gallon cost is the capital cost to install enough of a stormwater bmp to treat 1 gallon of runoff and it s how we often discuss the cost of stormwater management tools.
Green roof costs and benefits.
Increased r value a measure of the resistance of a material to heat flow of the roofing system along with reduced temperatures on the roof lessen hvac loads resulting in energy cost savings.
This paper evaluates the environmental benefits of green roofs by comparing emissions of no2 so2 o3 and pm10 in green roof material manufacturing process such as polymers with the green roof.
They are fairly lightweight and can be installed on roofs with a pitch from 0º to 30º.
Although installation of a green roof usually involves higher upfront costs than a traditional roof there are many economic benefits that can make up for this.
The epa estimates that the cost of installing a green roof starts at around 10 per square foot for simpler extensive roofing and 25 per square foot for intensive roofs.
An extensive green roof is the most common and least expensive type of green roof with costs ranging from 10 20 a square foot 2.