Title 24, part 6, of the California Code of Regulations, sets energy efficiency standards for residential and non-residential buildings. If you’re building a new home, you should consider buying the most energy-efficient doors possible.When selecting doors for energy efficiency, it’s important to first consider their energy performance rating in relation to the local climate.
Look for a low SHGC in a climate that mainly requires cooling and a high SHGC in a climate that requires heating. The range is from 0 to 1. SHGC measures how well a product keeps out solar heat.Look for a low U-factor; the range is from 0.00-2.00. The lower the U-factor, the better the door keeps in heat.
The newly updated California code for residential fenestration requires U-factor ratings of 0.30 or better and Solar Heat Gain Coefficient (SHGC) ratings of 0.23 or better.