Crawley Library Building

Principal Investigator(s): Professor Rajat Gupta


Project start: September 2011

Project finish: September 2013

Funded by: Innovate UK

About us

Category: Non-domestic in-use building performance evaluation.

Objective: Closing the performance gap of an award winning exemplar of sustainable public building design through a TSB-funded Building Performance Evaluation (BPE) study.

The overall project aim was to optimise the energy performance of the building by reducing the gap between the designed and actual performance. The study aims were:

  • Improve building performance by providing feedback on how a multi-stakeholder public client manages the building to support each end user group's very distinct needs.
  • Provide key lessons for future public building design, specification and performance.
  • Increase understanding of the relationship between intended performance and actual performance in use.
  • Identify the role of occupants in minimising energy use, from full time staff, social services outreach workers, to members of the public using council services.

Indoor view of the library


Rajat Gupta

Professor Rajat Gupta

Professor of Sustainable Architecture and Climate Change, Director of OISD and LCB Group

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  • A detailed assessment of annual energy consumption and generation was undertaken using CIBSE TM22 procedures. Actual energy performance was compared to benchmarks and other buildings.
  • Sub-metering arrangements were be calibrated, and energy demand profiles analysed using BMS data.
  • Long-term monitoring was undertaken of temperatures, humidity and CO2 levels to investigate the effect of ‘thermal mass’ in moderating temperatures.
  • To determine technical performance, spot checks and measurements took place in different seasons, using thermography, true power meters and luminance meters. Walkthrough surveys identified any wastage of energy.
  • Feedback from staff and visitors using BUS questionnaires ascertained whether needs were met in terms of performance, usability of controls for ventilation and lighting. Structured interviews with management investigated reliability, maintenance and maintainability.

Diagram of the Crawley Library Building


The study of Crawley Library provides insights into the issues that emerge and lessons to be learned in relation to design, commissioning, handover and management of a low carbon public building.

Initial findings of the study reveal insufficient handover training and documentation, frequent change in FM staff, unintended space usage and usability issues of controls and windows. Constant monitoring and feedback is crucial for fine-tuning the building’s operation and achievement of its environmental and service delivery targets.

It is crucial that this approach is absorbed and carried over after the end of the study to ensure future fine tuning and trouble shooting.

Diagram showing the library's high energy efficiency compared to similar buildings

Project details

Funded by:

  • Innovate UK (formally known as Technology Strategy Board)

Project Partners:

  • Penoyre & Prasad LLP
  • West Sussex County Council


  • Ramboll


  • Total project value: £81,000
  • Income to OBU: £58,100


  • Gupta, R., Kapsali, M. and Gregg, M. (2017) Comparative building performance evaluation of a ‘sustainable’ community centre and a public library building, Building Services Engineering Research & Technology, 1-20

  • Gupta, R. and Kapsali, M. (2015). A tale of two civic buildings: comparative evaluation of the actual energy performance of a ‘sustainable’ community centre and a public library building, Proceedings of CIBSE Technical Symposium 2015, 16-17 April 2015, London, UK