Circular Economy Lab


Circular Economy Options for HVAC

This project reviewed two buildings, 22 Gordon Street (ex-Wates House), and The Circular Building, a temporary building built along circular economy principles by Arup and BAM.

Executive Summary

The circular economy concept has gained momentum over recent years, but few have analysed its application to the building services sector. This project aims to contribute to unravelling this opportunity (and its constraints) as a joint interest between UCL IEDE, UCL Estates, and Arup, to create useful guidelines for the industry.

Building services fall within the ‘sweet spot’ for applying circular economy strategies. Some of the sector’s biggest issues such as; specialty equipment with high (upfront) costs, fast obsolescence, maintenance issues and costs, and the well-known performance gap can be dealt with by applying some of the strategies discussed in this report.

Using the Ellen MacArthur Foundation’s building blocks and ReSOLVE levers framework, the CIBSE TM56 report on Resource Efficiency in Building Services, and circular case studies found in the industry, this paper sets the base to understand the application of circular economy to building services.

Two case studies are analysed: 22 Gordon Street, as a business-as-usual design and construction project with a standard RIBA stages process and The Circular Building by Arup, as a temporary test lab where circular strategies were tested and products assembled together and successfully dismantled at the end of use. Interviews were carried out with four decision-makers involved in the design of 22 Gordon Street and three in The Circular Building to understand the decisions (and reasons) that influenced the selection of certain building services and their circularity according to the previous literature guidelines reviewed. Supporting design documents were then studied to understand the ordinal relationship between decisions and the stage at which these were taken.

For 22 Gordon Street it was found that the client’s (UCL) complex mix of internal bodies had the greatest influence in driving decisions through its managerial Estates department, facilities manager, BSA representative and technical team. Some of the decisions that most influenced building services and their circularity were not directly connected: the drastic change of brief and project scope, extending the building by two storeys, the specific architecture teaching space planning requirements and variety of users, the retention of the concrete frame and the design of the open atrium stairs. These and other building performance drivers led to the selection of the following key services solutions: a complex air-conditioning user control strategy, a centralised HVAC system with local multi-purpose chilled beam units, the resolution to install a new high voltage transformer, integrating the LED luminaires into the chilled beams, high-quality ‘gender-neutral’ toilets, a centralised DHW system, the need for a fire-dedicated core and other fire-safety services (a sprinkler system was not required) and the decision to avoid installing an extra lift.

On the other hand, The Circular Building demonstrated current methods of applying circular strategies to construction and building components. The most successful building layer in terms of circular economy was found to be the Accoya timber façade, and the following findings arose from choices made for its circular building services: digital material passports and the use of BIM, a 3D printed MVHR unit, sustainable Gatorduct cardboard ducts, a DC power network provided by a saline battery, plug-and-play power connections, recyclable Xicato LED lighting modules and a virtual controls system using Wi-Fi and IoT data monitoring.

Decision-making guidelines and a new RIBA Plan of Work are proposed to aid the design and procurement of circular building services. Conclusions identify two key drivers to accelerate the transition to a circular economy: better information gathering through digital technology, and business models shifting towards service/performance-based contracts.

A pdf of the entire report is available here.