1. What is a Heat Loss Calculator?

Definition: This calculator estimates the heat loss from a building or room based on U-values, surface areas, temperature differences, and ventilation losses.

Purpose: It helps heating engineers and homeowners determine the heating requirements for a space.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Total heat loss (Watts)
• \( U \) — U-value of the surface (W/m²K)
• \( A \) — Area of the surface (m²)
• \( \Delta T \) — Temperature difference (Kelvin)
• ventilation — Additional ventilation heat loss (Watts)

Explanation: The formula calculates conductive heat loss through surfaces plus any additional ventilation losses.

3. Importance of Heat Loss Calculation

Details: Accurate heat loss calculations ensure proper sizing of heating systems, energy efficiency, and comfortable indoor temperatures.

4. Using the Calculator

Tips: Enter the U-value, surface area, temperature difference, and any ventilation losses. All values must be ≥ 0.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical U-value for walls?
A: Modern insulated walls typically have U-values between 0.18-0.30 W/m²K, while older walls may be 1.0-1.5 W/m²K.

Q2: How do I calculate ΔT?
A: Subtract the outside temperature from the desired inside temperature (both in °C or K).

Q3: What's included in ventilation losses?
A: This accounts for heat lost through air changes. It's often calculated separately based on air change rates.

Q4: Should I calculate for each surface separately?
A: Yes, for accurate results calculate walls, windows, roof, and floor separately then sum the results.

Q5: How does this relate to boiler sizing?
A: The total heat loss Q indicates the minimum heating capacity needed for the space.