1. What is a Heat Loss Calculator for Underfloor Heating?

Definition: This calculator estimates the heat loss through floors based on the floor's U-value, area, and temperature difference.

Purpose: It helps heating system designers and homeowners determine the heating requirements for underfloor heating systems.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Heat loss (Watts)
• \( U_{floor} \) — Floor U-value (W/m²K)
• \( A \) — Floor area (m²)
• \( \Delta T \) — Temperature difference between inside and outside (Kelvin)

Explanation: The heat loss is calculated by multiplying the floor's thermal transmittance (U-value) by its area and the temperature difference.

3. Importance of Heat Loss Calculation

Details: Accurate heat loss calculation ensures proper sizing of underfloor heating systems, energy efficiency, and thermal comfort.

4. Using the Calculator

Tips: Enter the floor U-value (typically 0.10-0.25 W/m²K for insulated floors), floor area in square meters, and temperature difference in Kelvin (1°C = 1K).

5. Frequently Asked Questions (FAQ)

Q1: What is a typical U-value for floors?
A: Well-insulated floors typically have U-values between 0.10-0.25 W/m²K, while uninsulated floors can be 1.0 W/m²K or higher.

Q2: How do I determine the temperature difference?
A: Subtract the minimum expected outdoor temperature from your desired indoor temperature (e.g., 20°C indoor - (-5°C outdoor) = 25K).

Q3: Does this include heat loss through walls and windows?
A: No, this only calculates floor heat loss. You need separate calculations for other building elements.

Q4: Should I add a safety factor?
A: Yes, it's common to add 10-20% to the calculated heat loss to account for uncertainties and system efficiency.

Q5: How does this relate to underfloor heating output?
A: Your underfloor heating system's output should at least match the calculated heat loss to maintain comfortable temperatures.