1. What is a Slant Heat Loss Calculator?

Definition: This calculator estimates the heat loss through a slanted surface based on U-value, surface area, temperature difference, and angle of inclination.

Purpose: It helps engineers, architects, and energy assessors determine heat transfer through inclined surfaces like roofs or tilted walls.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Heat loss (Watts)
• \( U \) — U-value (W/m²·K)
• \( A \) — Surface area (m²)
• \( \Delta T \) — Temperature difference across surface (Kelvin)
• \( \theta \) — Angle of inclination from horizontal (degrees)

Explanation: The cosine factor accounts for the increased effective surface area when a surface is tilted.

3. Importance of Slant Heat Loss Calculation

Details: Accurate heat loss calculations for slanted surfaces are crucial for proper HVAC sizing, energy efficiency assessments, and building insulation design.

4. Using the Calculator

Tips: Enter the U-value (thermal transmittance), surface area, temperature difference, and angle of inclination (0° for horizontal, 90° for vertical). Angle must be between 0° and 90°.

5. Frequently Asked Questions (FAQ)

Q1: Why does angle affect heat loss?
A: The angle changes the effective area exposed to temperature difference and affects convection patterns.

Q2: What's a typical U-value for roofs?
A: Well-insulated roofs typically have U-values between 0.1-0.3 W/m²·K, but this varies by region and building code.

Q3: How do I find the temperature difference?
A: Subtract the outdoor temperature from indoor temperature. Use consistent units (Kelvin or Celsius).

Q4: Does this account for solar gain?
A: No, this calculates conductive heat loss only. Solar radiation would require additional calculations.

Q5: What angle should I use for vertical walls?
A: For vertical surfaces (90°), use our standard heat loss calculator as cos(90°) = 0 which would make the denominator zero.