Heat Loss Calculators

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A suite of tools to help with sizing new radiators correctly. Includes basic and advanced heat loss calculators and panel output tool to compare existing radiator outputs.

Basic Calculator

Use this heat calculator for a very rough idea of how much heat you need. It uses a basic method based on the volume of…

Advanced Calculator

A more in-depth, fully customisable heat loss calculator.

Panel Radiator Outputs

Calculate the estimated heat output of your existing panel radiators.

How To Use

1. Enter the width and height of your panel radiator
2. Select the panel type from the dropdown menu (use the images at the bottom of the page for help)

Considering an upgrade?

We make custom radiators for the modern home. 
Browse our complete range here.

LengthHeight RadiatorWatts 


What type of panel radiator do I have?

Upgrade to a Castrads radiator.  
Cast Iron Radiators | Steel Column Radiators | Bathroom Radiators

Cast iron panel

Single panel cast iron.
1340 Watts / m2

cast iron panel radiator illustration



Single steel panel

One steel panel with no convector fins.
1058 Watts / m2

Single steel panel radiator illustration



Double panel

Two parallel panels with no convector fins.
2271 Watts / m2

double panel radiator illustration


Single convector

One steel panel with convector fins.
1554 Watts / m2

single convector radiator illustration



Double plus

Two parallel panels with convector fins on one panel.
2354 Watts / m2

doubke panel plus radiator illustration


Double convector

Two parallel panels with convector fins on both panels.
2983 Watts / m2

double convector radiator illustration