1. What is Room Heat Loss Calculation?

Definition: This calculator estimates the heat loss from a room based on the U-value of surfaces, area, temperature difference, and ventilation losses.

Purpose: It helps HVAC professionals, architects, and homeowners determine heating requirements for spaces.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Total heat loss (Watts)
• \( U \) — U-value of the surface (W/m² K)
• \( A \) — Surface area (m²)
• \( \Delta T \) — Temperature difference between inside and outside (Kelvin)
• ventilation — Additional heat loss from air changes (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 occupant comfort.

4. Using the Calculator

Tips: Enter the U-value (thermal transmittance), 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 might be 0.3 W/m²K, while older uninsulated walls could be 1.5 W/m²K or higher.

Q2: How do I determine ΔT?
A: Subtract the outside design temperature from your desired indoor temperature (both in °C or K).

Q3: What's included in ventilation losses?
A: Heat lost through air changes, which can be calculated separately based on air changes per hour and volume.

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

Q5: Does this account for thermal bridging?
A: No, for precise calculations you should account for thermal bridges separately or use a lower effective U-value.