1. What is an Underfloor Heating Boiler Size Calculator?

Definition: This calculator determines the appropriate boiler size needed for an underfloor heating system based on floor area, BTU requirements, and a safety factor.

Purpose: It helps homeowners and heating professionals properly size boilers for efficient and effective underfloor heating systems.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Required boiler output (BTU/h)
• \( A \) — Floor area (square feet)
• \( \text{BTU/ft}^2 \) — Heat requirement per square foot (BTU/h·ft²)
• \( F_f \) — Safety factor (typically 1.2 for residential systems)

Explanation: The floor area is multiplied by the BTU requirement per square foot, then adjusted by a safety factor to ensure adequate capacity.

3. Importance of Proper Boiler Sizing

Details: Correct boiler sizing ensures efficient operation, prevents short cycling, and maintains comfortable temperatures while minimizing energy costs.

4. Using the Calculator

Tips: Enter the floor area in square feet, BTU requirement (default 25 BTU/h·ft²), and safety factor (default 1.2). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical BTU requirement for underfloor heating?
A: Most residential systems require 25-35 BTU/h per square foot, depending on insulation and climate.

Q2: Why include a safety factor?
A: The safety factor accounts for heat loss, system inefficiencies, and occasional extreme weather conditions.

Q3: When would I change the safety factor?
A: Use higher factors (1.3-1.5) for poorly insulated spaces or commercial applications.

Q4: How do I measure the floor area?
A: Calculate the length × width of each room, excluding permanent fixtures, then sum all areas.

Q5: Does this account for zoning?
A: No, for zoned systems, calculate each zone separately or consult a heating professional.