House Heat Loss Calculator

Heat Loss Formula:

\[ \text{Total HL} = \sum (U \times A \times \Delta T) + \text{Ventilation} \]

U Value (W/m²K):

W/m²K

Area (A):

m²

Temperature Difference (ΔT):

Ventilation Loss:

Total Heat Loss (HL):

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1. What is House Heat Loss?

House heat loss refers to the amount of thermal energy that escapes from a building through various pathways including walls, windows, roofs, floors, and ventilation systems. Understanding heat loss is crucial for designing energy-efficient buildings and proper heating system sizing.

2. How Does the Calculator Work?

The calculator uses the heat loss formula:

\[ \text{Total HL} = \sum (U \times A \times \Delta T) + \text{Ventilation} \]

Where:

\( U \) — Thermal transmittance coefficient (W/m²K)
\( A \) — Surface area (m²)
\( \Delta T \) — Temperature difference between inside and outside (K)
\( \text{Ventilation} \) — Heat loss through air exchange (W)

Explanation: The formula calculates conductive heat loss through building elements and adds ventilation losses to determine total building heat loss.

3. Importance of Heat Loss Calculation

Details: Accurate heat loss calculation is essential for proper heating system design, energy efficiency assessments, building code compliance, and identifying areas for thermal improvement in buildings.

4. Using the Calculator

Tips: Enter U-value in W/m²K, area in square meters, temperature difference in Kelvin, and ventilation losses in watts. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical U-value for walls?
A: Modern building standards typically require U-values between 0.15-0.35 W/m²K for walls, depending on climate zone and building regulations.

Q2: How do I calculate temperature difference?
A: ΔT is the difference between desired indoor temperature and design outdoor temperature for your location during heating season.

Q3: What affects ventilation heat loss?
A: Air changes per hour, building volume, and temperature difference. Mechanical ventilation and infiltration through cracks contribute to this loss.

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

Q5: How can I reduce heat loss in my house?
A: Improve insulation, install double/triple glazing, reduce air infiltration, and use heat recovery ventilation systems.