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Centre for Digital Built Britain completed its five-year mission and closed its doors at the end of September 2022

This website remains as a legacy of the achievements of our five-year foundational journey towards a digital built Britain

Over-engineering of systems is an often-hidden source of inefficiency in systems, which can add significantly to their building and running costs, and reduce the sustainability of systems. One cause of over-engineering is a cumulative effect of different stakeholders adding margins to the requirements and the specification of the system to mitigate against their own risks. The stakeholders often know that their system is overdesigned, but not by how much, because it is not operating at maximum capacity, and they don’t know the peak load requirements. Knowing margins on existing systems is a key consideration in investment decisions for alternations to the current building. The rationale for these margins is typically not shared, so that margins accumulate and cannot be challenged.   

Building on empirical research into margins on building services in hospitals, the research aims to develop: 

  • new, more systematic processes for thinking about, managing and deciding on margins in planning and modifying hospital buildings; 
  • a prototype digital tool to make margins explicit by tracking margins in terms of capability and peak loads and capturing the rationale for margins, and displaying them clearly, to enable more rational and coherent margin planning; and 
  • design recommendations for designing flexible building services with suitable margins. 


The project analysed the causes of the overdesign relating to procurement and specification and developed insights that can inform the decision making and management of building service projects. It also developed recommendations for designing flexible building services with suitable margins. 


Case study, interview, system design

Presentation at CDBB Week 2019

Next Steps

Developing evidence-based sizing guidelines for the building services in the NHS, predicting future energy use of hospitals and developing system architectures for flexible and upgradable building service systems.  

Project Status

This project was completed in 2019