Has the DOE evaluated ventilation of attics on cooling loads? What is the impact of ventilation?
See answer above. Back to Top The impact of insulation minimizes the effect of emissivity. All jurisdictions require insulation, therefore, emissivity should be disregarded because the heat load does not enter the building. As with all other energy efficiency issues, the greatest energy savings benefit is generated by implementing the first energy efficiency measure. Therefore, adding a roofing surface with a high solar reflectivity or a high emissivity has less benefit on a roofing system that is highly insulative. Emissivity should not be completely ignored for highly insulated roofing systems as it still impacts the surface temperature and, therefore, the roof’s contribution to the urban heat island phenomena.
