Most of the definitions and programs of green building identify energy savings as a key critera. Operating energy has the greatest environmental impact in any life cycle analysis, so any product which can reduce energy used in heating and cooling a building is very green. Additionally, the EPS foam used in ICFs does not produce any CFC’s or HCFCs, and does not contain formaldehyde nor any other gasses which might affect indoor air quality. Both the EPS foam and the concrete are highly durable and have a long service life with no repair or replacement costs. ICF material is very resource efficient and multiple manufacturing facilities bring the product close to the job site. ICF construction generates very little waste, much of which can be recycled on the jobsite.