NewsOfficesBCO’s ‘Guide to Specification’ for healthier offices updated to include increased levels of outdoor air supply plus 10m2 density ratio

British Council for Offices releases new design guidance for the post-covid workplace showing how to decarbonise and promote wellbeing and flexible working.
Joanna Watchman1 year ago7 min

The British Council for Offices (BCO) has released an early update to its Guide to Specification, its most recognised publication, providing expert advice on how to specify office space. Amongst the many recommendations are various measures to support healthier working environments – including increased levels of outdoor air supply.

Announced today, the update responds to challenges emerging from the pandemic and the accelerating need for the built environment to respond to climate change. The update offers designers guidance on how to create healthier offices that support changing working patterns – while reducing carbon emissions.

The BCO’s new recommendations include:

  • Increased levels of outdoor air supply
  • Adoption of 10m2 space-per-person
  • Minimum sustainability target of BREEAM ‘Excellent’ and 5 Star NABERS UK target for new buildings
  • Aspirational targets for operational and embodied carbon use to meet NZC (Net Zero Carbon) goals
  • More efficient lighting installations
  • Reduced power and cooling loads
  • Higher performance facades
  • More flexibility in the range of structural spans for office space

Changes to recommended occupancy density 

One of the main elements of this update is the BCO’s guidance on space allowed for each employee when designing a speculative office building. 10m2 per person is recommended as the occupancy density design standard for general workspace. The former high occupancy density allowance of 8m2 per person has been redefined as a special use case for exceptional cases.

10m2 per person is recommended by the BCO as the occupancy density design standard for general workspace

Designing for the 10 m2 per person occupancy density provides greater scope for the variety of workplace settings needed to support hybrid working. It also avoids overdesign of core services, improves floorplate efficiencies, and minimises carbon emissions.

Road to net zero carbon

The BCO acknowledges that many developers already target BREEAM ‘Outstanding’ for new offices. Reflecting the rapid progress in the sector in adopting more demanding sustainability targets, the Guide is moving its minimum BREEAM target rating from ‘Very Good’ to ‘Excellent’, and introduces the latest building certification standard, NABERS UK – an energy performance rating relying on measured energy use. The update recommends targeting a 5-star NABERS UK rating for new building design.

The selection of high-performance facades, lighting and building services systems should also be made with net zero targets in mind, prioritising energy efficiency.

Richard Kauntze, Chief Executive of the BCO, said: “The BCO Guide to Specification often described as the ‘design bible’ for the office sector is an essential resource for the decision makers who invest in, develop or design millions of square feet of office space every year. The 2023 Update will drive the decarbonisation of the office sector, enacting change to help the industry deliver on the UK’s net zero by 2050 target. This new guidance for the highest-quality offices introduces more generous space standards and greater design flexibility to support wellbeing and sustainability as the office sector adapts to the world of hybrid work.”

Neil Pennell, Chair of the BCO’s Technical Affairs Committee and Head of Design Innovation and Property Solutions at Landsec, said: “The BCO’s new guidance reflects changes in design thinking since 2019 driven by Net Zero Carbon targets, increased hybrid working post COVID-19, changes in regulations and improvements in equipment performance. There is a clear imperative to adopt a whole-building approach to decarbonise the sector which needs to start with the design and specification of new and refurbished office space. Developed in collaboration with the UK’s leading experts, the BCO Guide to Specification gives clear advice on how operational and embodied carbon can be reduced without compromising the need to provide flexible office space that meets the needs of occupiers and helps them to conduct their business in safe, healthy, comfortable and productive workspaces.”

The BCO Guide to Specification update has been developed in consultation with experts from across the industry, including agents, investors, occupiers, and developers.

About the BCO

The British Council for Offices (BCO) is the UK’s leading member organisation representing the interests of all those who occupy, design, build, own or manage offices in the UK. Learn more about the BCO at


Joanna Watchman

Joanna Watchman is our founder. She is a communications consultant specialising in the built environment and technology sectors. Having spent years writing, thinking and talking about the way buildings could (and should) be more in tune with the people that use them, Joanna decided to create Work in Mind. She is on a mission to bring together all those who believe in smarter, more connected human-centric buildings.

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