A turning tide for the measurement of buildings?

The recent Building Performance Network report, ‘State of the Nation Review: Performance Evaluation of New Housing’ was published this week. It certainly makes for an interesting read, showing consistent and sometimes large differences between as-designed and as-built performance.

State of the Nation Review

Across airtightness, elemental and whole dwelling thermal performance there are cases where performance is worse than predicted, but also cases where it is better. The report provides more evidence that we simply don’t know the real performance of our buildings, this alongside underwhelming policies based on predicted performance leaves buildings at risk of unintended consequences.

Given our knowledge of the importance and ubiquity of the performance gap, it’s both surprising and underwhelming that from this thorough review of academic papers, and other reports (which includes industry workshops and surveys) there are only 91 Building Performance Evaluation projects comprising 826 dwellings. For those interested, these projects are all mapped online by the BPN. Moreover, the report references a total of just 29 dwellings that have been subject to a whole house heat loss test (co-heating) and just 62 homes which have been subjected to wall U-value measurements.

In the UK we build anywhere between 100,000 and 250,000 homes per annum and yet we only measure the true performance of a small fraction. How can this be? We care so much about the fuel efficiency of our cars, efficacy of investments and the general carbon footprint of our actions yet we just accept our buildings for what they are, despite being the largest capital outlay many of us ever make and the place we spend most of our time.

It is this bizarre situation that drives us here at Build Test Solutions, and our mission to make building performance measurement more accessible and main stream is clearer than ever.

Thankfully in just the few years we’ve been in business, we’re already seeing some positive progress. Thanks largely to schemes such as ECO3 Innovation with its Demonstration Action and Monitored Measures strands, product suppliers and manufacturers have sought performance measurement on a scale unlike anything ever previously delivered.

With what’s in the pipeline, BTS alone will have measured the whole fabric heat loss in over 400 homes come the end of the 2020/21 heating season. Other initiatives such as Energiesprong have also been driving the business case for pre and post refurbishment performance monitoring with BTS again having also measured some 50x properties for Nottingham City Homes and Sutton Housing over recent months. A number of major house builders are also using our techniques to much more cost effectively evaluate their various house types; driven by their own recognition of the value offered by performance measurement as well as in some cases by requirements set out by Local Authority led planning conditions or Homes England funding terms.

As we make more practical and cost effective measurement solutions available, we are beginning to sense an impending turn in the tide where building performance evaluation can and should shift from a highly niche cottage industry to one where measurements of the true performance of buildings are able to become commonplace as EPCs.

Download the State of the Nation Review: Performance Evaluation of New Housing.


Luke Smith

Luke Smith

Managing Director

Building performance measurement made simple.

Unique products and smart technologies designed for energy assessors, building surveyors, the construction industry, utility suppliers and other built environment experts.

Temperature sensors

Measured Thermal Performance

A low-cost and non-invasive way of measuring the true thermal performance of a house. It requires temperature and meter data to calculate an accurate heat loss rating over a 3-week period.

Learn more about Measured Thermal Performance
ISO 9869 U-value measurement system

ISO 9869 U-value Measurement System

System for measuring in-situ U-values of walls, floor and ceilings according to the ISO 9869 methodology.

Learn more about ISO 9869 U-value Measurement System