Heat Loss Calculator

Confidently calculate heat loss on a room-by-room basis.

EES Data Heat Loss Calculator Software

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EES Data Heat Loss Calculator Software


Our Heat Loss Calculator has been developed to provide contractors with a quick and straightforward method for working out heat loss. Our Windows-based tool makes it easy to calculate heat loss on a room-by-room basis, even for complex projects.

•⠀Latest version of the software
•⠀Access to future updates and releases
•⠀Support via phone and email
•⠀Online remote assistance

Please note: Multiple licences are required to install on multiple PCs.

Latest update

Install options



+ VAT (per licence/per year)

How to download the Heat Loss Calculator software

Please use the PayPal checkout link above to make payment for the software, or alternatively contact us to arrange payment via another method if you prefer.

On receipt of payment, we will dispatch an email containing a download file so you can install the Heat Loss Calculator software. Please contact us by email if you do not receive a confirmation within 24 hours after making a payment.

How to calculate heat loss

It is necessary to calculate heat loss when planning to install any heating system. This is so the required heating power can be calculated in such a way that compensates for heat loss. Any building will lose heat at a certain rate as long as the exterior temperature remains lower than the interior.

Factors that influence heat loss include: the materials with which the building is constructed and insulated; the surface area of exterior walls; the size and construction of the floor and ceiling; whether and the difference in temperature between inside and outside the building.

Clearly there are a number of factors involved, but it is vital to estimate this accurately. This will help ensure adequate measures are put in place to reduce the effect. In the interests of accuracy, using our Heat Loss Calculator software is a highly advisable alternative to making manual calculations.

How our heat loss calculation software works

We worked with the Heating and Hotwater Industry Council to re-develop their original heat loss calculator software, building a new version of the program that works on Windows operating systems, including Windows 10.

Our heat loss calculation software estimates room heat losses in accordance with the latest CIBSE/IDHEE domestic heating design guide. The software is also specified for use in Microgeneration Certification Scheme documentation as a means of calculating the sum of heat losses on a room-by-room basis.

The latest version of the program (Version 6.42) also includes access to all future updates, and is available for download via a secure link. User licences, updates and a technical support package are all available as part of one single subscription.