This video has some very informative information about the value of Spray foam insulation when compared to conventional insulation.
“A materials R-value is its resistance to heat flow. Spray foam creates double the value of conventional insulation … and helps keep conditioned air inside and unconditioned air outside. Convection gets started when hot and cold clash inside a wall cavity, which leads to moisture. Moisture acculumulation can lead to mold growth and other allergies and premature deteriation of building material.”
“According to the US department for energy heating and cooling accounts for 50-70% of the energy that is used by the average American home.”