BS 40101 Building Performance Evaluation Standard Public Consultation

BS 40101 aims to support the mainstreaming of Building performance evaluation (BPE) to maximise opportunities for feedback and learning and drive improved performance of new and renovated/retrofitted buildings, accelerate the trajectory to net zero carbon (in operation) buildings, support and inform the energy system transition, and reduce waste and running costs.

Consultation responses

The draft of an exciting new British Standard, BS 40101 – Building performance evaluation of occupied and operational buildings, is now available for public consultation via BSI’s standards development portal at

Whilst interest in actual (rather than theoretical) performance of buildings has grown over recent years, there is currently no basis for specifying a consistent approach to building performance evaluation (BPE). This inconsistency means that BPE findings are often incompatible, limiting the benefit of aggregation or meta-analysis and often focusing any review and challenge of BPE findings on the methods and approaches deployed, rather than the results obtained.

By providing this British Standard, the aim is to support the mainstreaming of BPE with potential for feedback and learning, as well driving improved performance of new and renovated/retrofitted buildings; accelerating the trajectory to net zero carbon (in operation) buildings, supporting and informing the energy system transition, reducing waste and running costs.

Customers of BPE clearly need to have confidence that performance has been evaluated in a consistent way, allowing for comparison (e.g. against specification or design prediction, before and after retrofit, between similar buildings, or against industry benchmarks), repeatability and robustness of results.

Providing such a standard also stands to enable performance outcomes to be linked to financial products (e.g. mortgages, “pay as you save” arrangements), regulatory and contractual compliance.

Developers and contractors seeking, or being required, to meet specific levels of operational performance may also use the standard to provide a consistent basis for planning for evaluation and verification, thus providing clients with greater confidence that this will be carried out to an acceptable standard.

A draft of the standard is currently open for public consultation, with a deadline for commenting of 28th August 2021. Note, if using the BSI website for this purpose for the first time, registration is required.


Luke Smith

Luke Smith

Managing Director

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