Proven to Be Energy Efficient
Citadel’s thermally broken lines of steel and aluminum windows and doors have surpassed the most stringent energy performance requirements in the fenestration industry.
With U-values (U-factors) as low as 0.13, CWD thermal windows and doors are both certified by the National Fenestration Rating Council (NFRC) and compliant with California Title 24 Building Energy Efficiency Standards. This excellent energy efficiency also comes with narrower sightlines and greater strength.
NFRC-certified windows and doors must receive strong energy performance ratings for their U-Factor, Solar Heat Gain Coefficient (SHGC), Visible Transmittance (VT) and Air Leakage. The California Title 24 Building Energy Efficiency Standards largely follow these energy efficiency requirements for fenestration products and exterior doors.