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Heat Loss

Heat Loss is the total amount of heat lost through the fabric of your building - such as roof, walls and windows.

IMPORTANT: You should never rely on your old fossil-fuel boiler’s output to select the size of your new electric boiler.

Always insist on a heat-loss calculation.

Googling the output of a heating system is easy. But you should always buy boilers in line with your entire property’s unique heat loss.

This can also be done room-by-room for electric panel radiators.

Insulating walls, roof spaces, and other air leakage hotspots will slash your heat loss. This means wasting less money replacing all that precious warmth.

And your investment in good-quality insultation makes a positive contribution to fighting global temperature increases.

Heat Loss in home

How is Heat Loss Calculated?

Our experienced energy sales team will visit your home and take measurements of all your rooms, window and doors. During the visit they will, where possible, also determine the construction of walls, floors and roofs, as well as the type of window glazing - single, double, etc. 

These specific measurements are then entered into our heat loss calculator, along with the type of property construction as identified above. Each type of construction will have its own heat loss value.

For example a single-block construction wall has a much higher heat-loss value than a single-block construction wall with a 50-mm thermaboard installed. 

The final calculation will give the heat-loss per room and for your whole property. These values will then be used in your bespoke quote to ensure you have the correctly sized electric boiler, or electric panel rads for individual rooms. 

Carbon Emissions

Your property's individual heat loss figure will determine how much carbon you'll save when you switch to electric heating. 

For example, a property with a 10.2 kWh heat loss that uses heating for 1,350 annually could save up to 3 tonnes of carbon each year when switching from gas - or up to 4 tonnes when switching from oil central heating. 

This also demonstrates the value of property insultation. Less heat loss means spending less money and emitting less carbon. 


If you haven't already, speak to us about a free home survey.