Assembly Bristol

Reception area at Assembly Bristol, UK. A large screen with BT is fixed to the wall.

Assembly Bristol

Established nearly 200 years ago, BT Group is a leading multinational telecommunications services provider, employing over 100,000 people and generating more than 20 billion pounds in revenue in 2022. In May 2018, the company announced The Better Workplace Programme, a five-year initiative aiming to deliver inspiring buildings championing social, networking and cultural benefits while prioritizing work-life balance; improving its corporate sustainability profile as part of the Drive to Net Zero effort; seeking to reduce maintenance costs; and increasing productivity. 

Due to be completed by 2024, The Better Workplace Programme, one of the biggest of its kind in the U.K., involves more than 300 BT Group offices being consolidated into around 30 hubs located across the country. HDR provided holistic building engineering services on three facilities, namely: London’s One Braham, The Better Workplace Programme’s flagship building and the organization’s new global headquarters; Riverside Tower in Belfast; and Assembly Bristol.

Having opened in autumn 2022, Assembly Bristol is now serving as a hub for up to 2,500 BT Group employees in the West of England, delivering on the company’s goal to increase its presence in the area as well as bringing a significant investment in the region. The development is located alongside a floating harbor, offering spectacular views of Bristol's regenerated waterside heritage and complementing the city’s famous Temple Quarter Enterprise Zone, a series of well-connected and thriving mixed-use communities.

Between late 2019 and autumn 2022, HDR provided a comprehensive engineering design and delivery solution for Assembly Bristol, taking the building over from the base build stage and proceeding directly to the CAT B fit-out systems installation phase, omitting the CAT A stage. This design approach allowed the architect’s vision for exposed services to be achieved. Additionally, many of the engineering aspects were designed to be built into the shell and core. Utilizing best practice from the One Braham project, we proposed a bespoke solution, helping the client to achieve efficiencies and reducing costs.

HDR designed the following services: mechanical, electrical and public health; controls; lighting; information communications technology; audio visual; sustainability; and structures, including a complete structural design for the fit-out works, with new staircases and riser openings. Additionally, we supervised a third-party contractor undertaking fire protection services.

Early Engagement

BT Group approached HDR for discussions on Assembly Bristol very early stage in the program, to assess the suitability of the shell and core for the implementation of engineering design solutions required to support The Better Workplace Programme ethos. HDR tested the base build approach against the desired outcome before the commencement of larger works, providing recommendations and undertaking early interventions; for example, there was a requirement for a unique delivery strategy as plant rooms were comparatively small for a building of this size, meaning smaller modular units had to be fitted internally.

Assembly Bristol is one of the first buildings to become part of the Bristol District Heating Network, a system of underground pipes that provides affordable, low-carbon heat and energy to both businesses and homes across the city. These types of schemes (plans) are not commonplace in the U.K., showing the innovative intent of BT Group for The Better Workplace Programme. Further emphasising the sustainability elements of the project, the scheme features photovoltaic panels and utilises electric air source heat pumps as opposed to traditional gas boilers. Assembly Bristol is projected to save 140 tons of carbon dioxide annually, raising to more than 500 tons as BT Group consolidates its estate portfolio in the area.

Following the coronavirus pandemic, one of the focal points of employee well-being efforts within Assembly Bristol was the quality of air. Already pre-COVID, HDR had proposed an engineering solution that delivered air quality at a standard far exceeding requirements for the level of occupancy, particularly in areas where larger numbers of people would congregate.

HDR utilized the significant amount of glazing in the design and avant-garde solar controlled glass, enabling sunlight to pass through windows whilst simultaneously blocking heat and thus regulating indoor temperature. This solution allowed for an abundance of natural light, as specified in the architect’s concept, highly associated with improving moods and helping staff feel calm and focused.

Agile Flexible Working Solutions

The new office features a multitude of facilities, including interconnecting event spaces and a range of flexible agile collaborative workspaces, a restaurant, secure 250-unit bike storage, showers and changing rooms. The ICT team provided first-class connectivity with a high-end, buildable and resilient networking Wi-Fi connection reaching every inch of the building, enabling staff to work from wherever they desire. Plant areas were installed on levels 6 and 11 to support the bespoke in-house catering provision.


Trust and communication between BT Group, HDR, the architects, designers and other third-party consultants, such as specialist lighting and acoustic engineers, was paramount to the successful delivery of the project. Remote bi-weekly review meetings occurred in accordance with COVID restrictions; an innovative 3D BIM model was uploaded online and utilized by all remote teams to help keep the project on schedule and to provide all stakeholders access to the all the data. 

Having previously worked on One Braham, BT Group's new headquarters in London, HDR made informed decisions in advance and streamline the project. This effort was underpinned by the trusted professional relationship we have nurtured with BT Group on a global scale over the past 15 years, having worked across a portfolio of successful developments. 

HDR provided a comprehensive engineering design and delivery solution emphasising employee well-being as well as organisational objectives at every step of the journey. We delivered a truly bespoke service, with due consideration given to all aspects of the project, from conceptual holistic overview down to each and every detail, for example our minimal approach to cabling throughout the development to match the exposed services aesthetic. 

In accordance with The Better Workplace Programme, our experts were cognizant of both the broader ethos as well as local sensibilities, such as Bristol’s heritage and the community-focused efforts by harnessing Bristol’s District Heating Network. Assembly Bristol will provide the company with sustainability credentials as well as the ability to expand its digital services and increasing its presence in the region.

Reception area at Assembly Bristol, UK. A large screen with BT is fixed to the wall.