A Year Ahead in Measurement

As we reach the middle of 2024, this summer is set to be busy for the UK. As well as a July general election, the UEFA European Football Championship and hopefully some more sun, there are some exciting developments ahead in the world of building performance measurement. Here is a quick summary of what regulations, guidance and consultations you should be keeping an eye on during the second half of this year.

New RdSAP 10 methodology

This new methodology will permit the use of measured airtightness data for the first time in the delivery of energy performance certificates (EPCs) for existing dwellings. By using measured data rather than assumed values, homes could see EPC ratings improve by two or three points. This is expected to go live in August, despite some delays, but it should help drive considerable interest around airtightness testing in existing properties.

MCS heat load calculator

In the coming months we will see the launch of a new MCS BS EN 12831 compliant heat load calculator, that will support room-specific heat loss calculations and calculation of peak heat demand. Most exciting of all is that measured heat transfer coefficients (HTC), airtightness and U-value measurements will all be able to be inputted into the calculator for more accurate assessments.

ECO4 Pay for Performance

Despite some delays, the Department for Energy Security and Net Zero (DESNZ) is committed to making this a reality this year. Energy companies will be able to measure whole building heat loss pre- and post-retrofit in support of their ECO submissions (up to 10% of their total obligation). This all in place of deemed scores, thus providing an incentive to not only deliver fabric improvements of the highest quality and performance but to also encourage the use of additional measures not traditionally funded by ECO such as draught stripping, airtightness and party wall insulation.


Publicly funded retrofit projects are slowly swapping from the 2019 to the 2023 version of PAS2035.

The new British Standard:

  • Requires all projects to adopt airtightness testing and compliance with Annex C around ventilation
  • Places greater emphasis on post-retrofit evaluation, testing and monitoring
  • References BS40101:2022, which provides a clear framework for conducting building performance evaluations.

BS 40104 Retrofit Assessment Standard Consultation

This is expected any day now and sets out what a high-quality retrofit assessment should look like.

This standard is set to make a strong link between energy assessment and building surveying practices. It encourages deeper investigations that help inform retrofit designers, such as using data from airtightness tests, moisture and humidity logging and HTC and U-value measurements.

Social Housing Decarbonisation Fund Wave 3

Guidance was published in May that confirms that funding will continue to be focused on performance outcomes (albeit EPC ratings!). There also remains a strong focus on innovation, especially around digital solutions, like monitoring devices and finance models, such as measurement/outcomes-based finance.

Future Homes Standard Consultation response

Earlier this year, the new-build FHS consultation proposed strengthening the requirement for ventilation system testing and commissioning as well as mandating airtightness testing on material change of use (MCH) projects for the first time. It also proposed that incentives be given to developers who carry out whole-building heat loss measurements on a sample of properties. We might not see this regulation in action until 2025/26, but it is sparking an interest in developers and changes in local planning policies who want to get ahead of the curve.

There is a lot of change happening in the measurement industry and these are only the changes that we currently know about. With the possibility of a new government or the growing market-driven role for measurement in the finance, insurance and dispute resolution sectors, the call for building performance measurement related services is only going to become more commonplace.


Luke Smith

Luke Smith

Managing Director