With an R-value of 17.5 (3.09 W/Msq) a U-value of .057 (.324 Msq/W), and one of the best overall air infiltration ratings in the industry, the Thermacore® 599 Series is one of the most thermally efficient door systems in its class.
The Thermacore® line features steel-polyurethane-steel panel construction which provides a thermal barrier that withstands extremely hot or cold climates and the most demanding environmental requirements.