DOOR INSULATION
Each model utilizes a 25 gauge exterior steel skin. Chosen for their
weather resistant features, models 2251/4251 utilize a 1-3/8" thick
CFC free polystyrene insulation, while models 2255/4255 employs a 9/16" thick
CFC free polystyrene insulation with vinyl back covers. Steel end and intermediate stiles are held firmly in place by a tab-loc system, creating increased strength and rigidity.
2251/4251 R-value - 7.94
2255/4255 R-value - 3.56