Spray foam verses fiberglass?
Fiberglass allows air to flow through it, spray foam does not. This is the one aspect which sets spray foam apart from fiberglass. Studies from the Energy Department have shown that air infiltration plays a big a part in energy loss. Air infiltration is amplified by pressure differences from the inside to the outside a home driving air leakage through the tiniest cracks causing significant heat loss. Fiberglass also allows air to move within the stud cavity, when the temperature is warm on one side than the other a convection loop starts to occur allowing air to move in a circular flow allowing more energy loss to occur. This is why many people feel drafts in there home or they can feel air flow at electrical outlets. With spray foam it stops any air infiltration and air movement. This is the main reason you can save up to 40% in energy costs.
