Window U-Value Calculator
Estimate the U-value and energy rating of a window based on glazing layers, gas fill, and frame type.
How to Use the Window U-Value Calculator
- Select the number of glass layers.
- Select the gas fill type.
- Select the frame material.
- Click Calculate to get U-value and energy rating.
使用场景
- •Comparing window specifications.
- •Building energy compliance checks.
- •Renovation upgrade planning.
- •Passive house design.
公式
U = 1 / R_total. R_total = R_glass + R_gas + R_frame + R_air_films.
常见问题
What is U-value?
U-value (thermal transmittance) measures heat loss through a window. Lower is better.
What is a good U-value for windows?
Triple glazing with argon: ~0.8 W/(m²·K). Double glazing: ~1.2–1.8. Single: ~5.0.
What gas fill is best?
Argon improves insulation over air by about 10–15% due to lower thermal conductivity.