What is the 'R' value of garage door insulation?

The R-value of garage door is its resistance to heat flow. This value is used to denote the thermal efficiency of the door's insulation. Garage doors that possess higher R-values have superior insulation capabilities, as opposed to doors with lower R-values that provide poorer insulation.

Insulated garage doors work to maintain a constant temperature within the garage. Climate plays a major factor in choosing the appropriate garage door. Those who live in moderate climates can buy garage doors with lower R-values, while those who live in harsh climates should purchase doors with higher R-values. Polyurethane and polystyrene are widely used as insulation for garage doors. Polyurethane provides a much better level of insulation than polystyrene.