The Building Services Portal Heat Pump Assessment Calculator

The Building Services Portal heat pump assessment calculator is the simple method for homeowners and contractors to quickly estimate a suitable boiler replacement heat pump system. Answer the 12 questions in the below embedded spreadsheet (desktop and tablet only) and the calculator will generate an assessment report based on the given information. The report generated includes estimates of heat pump size, hot water cylinder size and installation costs. Download the free version to access the guidance and technical notes.

Please be patient as the below spreadsheet loads.


Select one option for each question. Click on each orange cell to reveal the options. The report generated is based on typical size and type of properties for the given answers. Further guidance and technical notes are contained within the downloadable free spreadsheet in the link below;


£ Free


  • Excel format
  • Download now or try using the embedded spreadsheet above
  • 12 simple questions
  • Easy to understand assessment report automatically generated
  • For home-owner use
  • Clear easy to follow instructions included
  • Building Services Portal guidance and technical notes included


£ 99 (incl. VAT)

All features of the basic version plus…

  • For contractors/ heat pump installers to give potential clients estimates prior to detailed design
  • Add the property and customer details to the form
  • Add your cost estimates to the report
  • Features your company logo or business details and the watermark removed for professional presentation 
  • Customer support- Our team of Chartered Engineers respond to all product related questions within 1 working day

Further Heat Pump Assessment Calculator details...

Free Version

Easy to Use

The Building Services Portal Heat Pump Assessment Calculator is the fast effective method for estimating the size and scope required to convert residential properties from gas fired boiler systems (or electric heating systems) to high-efficiency heat pump systems. It is aimed at homeowners to give them an understanding of installation scope and the high-level costs associated with installing a heat pump system.

There are many different types of heat pump systems available. This assessment tool is for high-efficiency, air-to-water type heat pump systems. These are typically installed in residential properties and qualify for the Government ‘Boiler Upgrade Scheme’ (£5,000 contribution). There is more information on the ‘boiler upgrade scheme’ on the government website, and this needs to be applied for by your selected installer.

Simply answer the 12 questions and the heat pump assessment report is automatically generated.

The heat pump assessment calculator spreadsheet includes detailed instructions for use and technical notes. Simply click on the relevant tab at the bottom of the page to display the different sheets containing the guidance.

Download the free version now.

Premium version

Present estimations professionally

The Premium version is ideal for contractors to professionally present initial heat pump system estimates. The Premium version includes your company logo which makes it ideal for presenting calculations to clients. Your logo will be in place of the Building Services Portal logo.

Premium features

There is additional space to enter the client’s details and date.

The cost estimates that are in the free version are removed so that you can insert your own estimations here. Also, there is a section at the end to insert your own terms and conditions.

The trial version watermark is removed.

The Premium version comes with the added benefit of customer support. Our team of Chartered Engineers will respond to any questions related to the Heat Pump Assessment Calculator within 1 working day.

We are confident you will be happy with your purchase but offer a no quibble 90-day money back guarantee.

Premium Heat Pump Assessment Calculator- £99 (incl. VAT)