Green roof components in italy green roofs are not very common yet even if they are starting to spread.
													
																	Green roof vs traditional roof. 
								
	
		
	
																	1 2 in addition green roofs can reduce building energy use by 0 7 compared to conventional roofs reducing peak electricity demand and leading to an annual savings of 0 23 per square foot of the roof. 
																	Green roofs are covered with plants and vegetation bringing a number of excellent benefits to every building. 
																	Cool roofs are even cheaper than green roofs only costing 0 75 to 1 50 per square foot and a single ply cool roof membrane usually ranges from 1 50 to 3 per square foot according to. 
																	As with anything though there are a few negatives and this post will aim to highlight both the advantages and drawbacks of implementing a green roof the benefits of. 
															
													
								
	
		
	
																	The issue of the italian standard uni 11235 2007 â œinstructions for the design execution control and maintenance of green roofsâ istruzioni per la progettazione lâ esecuzione il controllo e la manutenzione di coperture. 
																	We chose a value of 05 for existing dark roof solar reflectance because a typical roof is covered in black tar which has a solar reflectance value less. 
																	Because the calculator we used compares green roofs to traditional roofs the calculator has the r value of traditional roofs built in. 
																	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.