How To Calculate Heat Gain

Heat gain calculation is crucial for energy efficiency and comfort in buildings. Understanding and managing heat gain helps reduce energy consumption and carbon footprint.

1. Enter the area, temperature difference, and U-value in the respective fields.
2. Click ‘Calculate’.
3. View the results below the calculator.
4. Interpret the chart for visual representation of heat gain.

The heat gain (Q) is calculated using the formula:

Q = U * A * ΔT

where:

• U is the U-value (W/m²K),
• A is the area (m²), and
• ΔT is the temperature difference (°C).

Comparison of U-Values for Different Materials

Material	U-Value (W/m²K)
Brick	0.8 – 1.2

• Improve insulation to reduce U-value and heat gain.
• Use reflective materials to reduce solar heat gain.
• Consider natural ventilation and shading.

What is U-value?

The U-value is a measure of heat transfer through a building element, such as a wall or roof. It’s the rate of heat loss in watts per square meter per degree of temperature difference (W/m²K).

Energy Efficiency & Renewable Energy Glossary – U.S. Department of Energy

Heat Transfer and Thermal Mass – Building Science Corporation