The Lindal windows are energy efficient with the highest industry rating for their ability to prevent air and water infiltration under the toughest test conditions. State-of-the-art, low-E argon glass is our standard for comfort, energy efficiency, and reducing fading of draperies and furniture fabrics. Relative to heating prices in your area, the cost to heat a Lindal home is usually lower than comparable homes. Due to the quality of materials and construction methods, a Lindal home is an energy-efficient home.