Heating Energy Calculator

If you’re wondering what size radiator do I need? Our Heating Energy Calculator can help you calculate your room's BTU needs. This will ensure your radiator is the right size and offers the correct heat output (watts) to heat your room efficiently without wasting energy. 

Our calculator is only designed to give you an idea of the heat output you need for each room. For a more detailed estimate, you should contact a member of our team on 01205 280354. We accept no liability for any errors resulting from the estimates given. Calculations are based on Delta-T 50°C (Δ-T50°C) in accordance with BS EN 442. 

What do you need to know to calculate the BTUs?

All we need to know is room dimensions (length, width and height) what type of room it is, what height the ceilings are, how many walls are externally facing (and what are they made of), and finally what is above and below the room. 

The calculator can then estimate the BTUs and watts your room needs to keep you warm. The figures given are based on a property with uninsulated (air gap) cavity walls, wooden floors, and a 2.4M high ceiling with a proportionate double-glazed window area.

For insulated cavity walls, deduct 20%, and for solid walls, add 10%. This basic heat loss calculator makes various assumptions based on your choices and may not take into account all factors relating to your particular requirements.

Once you know your required BTU, look at our range of ornate and traditional cast iron radiators to find one that’s perfect for your space. You may also find our informative blogs interesting, start with: 

What are the standard radiator sizes? A comprehensive guide to common dimensions

Manual or Thermostatic Valves: How to Choose

Paladin Radiator Product Guide: Top 10 Classic Cast Iron Models for Your Home