An innovative response to an extraordinary brief – to create ‘a building to house the world’ - PEARL at UCL’s campus in Dagenham is the university’s first Net Zero carbon in-use building: a unique, purpose-built laboratory facility for the creation of full-size environments.
Designed to test how people use infrastructure and cities, the Person Environment Activity Research Laboratory (PEARL) at UCL is equipped with minutely controllable indoor environments and sound systems, to test the effects that factors such as space, colour, lighting, smell, visibility, appearance, and touch can have on behaviour. Every core aspect of the building’s design – from background sound levels and low reverberation, to the black laboratory interior – has been carefully considered, intended to desensitise people’s awareness of ‘being in a building.’
Designed by Architects Penoyre & Prasad, B&K Structures delivered a hybrid timber-steel solution for the landmark facility, utilising offsite manufacturing techniques to meet the project’s strict programme, challenging site conditions and high sustainability requirements. On behalf of VolkerFitzpatrick, BKS as the specialist timber subcontractor designed, manufactured and installed the steelwork and timber elements, working closely with timber engineers Engenuiti and CLT manufacturers Stora Enso.
BKS’ work included the design and delivery of the outer portal steel frame, which internally shelters the two storey, 62.2m x 11.8m engineered timber ‘Groove’ building. Functioning independently of the main volume of the ‘life laboratory’, this facility provides flexible workspaces, seminar rooms and workshops. The project team worked collaboratively to BIM Level 2, with all disciplines submitting detailed designs to create a ‘federated’ model that was evaluated for clashes prior to commencement of the build, meaning the manufacture and sequencing of the timber elements for the Groove achieved the highest level of accuracy.
Clive Fussell, Director at Engenuiti, commented:
“It is increasingly vital as timber designers to understand, from the earliest stages of a project, how things will go together in terms of connections, the limits on erection, and manufacture in order to minimise wastage during manufacture and logistics.
Because the CLT Groove had to be erected within the steel-framed superstructure, head height was limited and this restricted the lift for the mobile cranes, which in turn limited the length of panel that could be included in the design. This required a lot of coordination between Engenuiti, BKS and their erectors at the design stage.
Due to the span of the glulam beams and lack of CLT cross-walls, the Groove is braced against the main steel frame to offer transverse stability, and the projecting CLT windows bridge the service void between the main timber structure and the outer cladding.”
The PEARL facility consists of a timber structure being built within another steel structure; providing a two-storey space for seminars, testing and trial fabrication, while larger urban environments can be evaluated in the factory-style main space. Delivering the project to schedule while meeting the unique end goals for the interior environment also depended on optimising the combination of different systems and building technologies, in a truly hybrid solution.
Tim Cloves, Project Manager for VolkerFitzpatrick, commented:
“We were employed by UCL to provide a CLT office space within a large portal framed building. Our original intent was to construct this concurrently with the steel frame being erected around it.
However, through the early stages of design, it became apparent that the sequence in which we would have to install services in this space did not allow for the two structures to be constructed concurrently.
This caused an issue in extending the duration required before we could commence with the outer skin of the roof and walls. To avoid this, B&K Structures were employed to design and build an offsite solution that could be installed after the steel frame had been constructed. This became an excellent solution enabling us to coordinate the services install alongside our programme and allow the outer layer works to be completed at the same time.”
The 4,000m2 space is formed by a portal steel frame comprising unusually complex trusses, with the outer envelope constructed using 160mm thick CLT panels that define the Groove. Designed by timber engineer Engenuiti, these panels also incorporated the creation of 13 bay windows, which span the metre-wide external service void without the need for temporary propping during construction.
One key challenge was the quantity of exposed timber throughout the building, requiring a number of brackets and other connections to remain visual. While many plugged screws were used, precision manufacture of the CLT by Stora Enso was also beneficial – with holes for pipes and cables routed in the factory. Sequencing was crucial as it had to be coordinated with the M&E install, as many spaces would never be accessible again.
A unique aspect to the build was the exclusion of a visible concrete upstand and skirting. To achieve this, the CLT wall panels were machined to extend 20mm down the inside face of the upstand creating a shadow gap. Due to the accuracy of the floor slabs, along with the engineered timber, this produced a seamless interface between the CLT structure and the concrete floor slab.
The selection of structural timber for the Groove also provided several onsite benefits when benchmarked against a traditional approach, including reducing the working hours required, the size of the installation workforce and overall programme time, while benefitting logistics and health & safety.
Craig Robinson, BKS Operations Manager, reflected:
“The quality we have delivered on this ground-breaking project could not have been achieved without strong collaboration between project partners, particularly between BKS and our supply chain partners Engenuiti and Stora Enso.
In particular, early consideration of design and manufacture has been key to delivering this innovative system to an impeccable standard. The use of offsite construction and the expertise of all project partners has enabled the onsite works to run smoothly and to the client’s satisfaction.”
Ultimately, this solution ensured the rapid and cost-effective completion of a complex, energy efficient building, which helped secure the UK’s first ‘Outstanding’ award under 2018 BREEAM requirements.
From the outset, UCL wanted PEARL to achieve Net Zero carbon in use. However, this demanded extremely high standards of performance for both the building and its sophisticated selection of M&E services, while embodied energy and environmental impact were also given close consideration.
Engineered timber is well recognised for its sustainability benefits, making it an ideal solution to achieve the low carbon design vision at PEARL. Early on, Aecom undertook a Circular Economy review, taking into account factors including the embodied energy of materials, strategy for demountability, and the potential for recycling component parts: all key advantages of building with structural timber.
To meet the strict sustainability requirements, VolkerFitzpatrick brought on a Sustainability Manager to advise on optimising the energy performance of both the completed facility and its construction. As part of this, they modelled the carbon of the finished building using E-tool LCA software, while BKS and their supply chain partners were able to provide accurate figures for the amount of carbon sequestered by the engineered timber structure, along with its other environmental impacts.
These included fewer lorry deliveries and reduction of energy intense materials including cement, helping lower the embodied carbon of the engineered timber structure while also facilitating a build where both site storage and working space were restricted. In addition, all timber used for the PEARL project came from PEFC certified sources, ensuring all trees are replaced with new growth.
The sequestered carbon of the timber significantly contributed to the project’s environmental assessment. BKS’ package included 592m³ of engineered timber from sustainable sources, mainly sourced from Northern Europe, delivering maximum points at MAT03 under the latest 2018 version of BREEAM and sequestering 379 tonnes of CO2e.
In addition to other measures including rainwater harvesting and electric car charging points, an area of rooftop PV panels - equivalent to the 4,000m2 floor area - produces circa 693 kWp, generating 129% of predicted average consumption, and powering air source heat pumps along with LED lighting and other equipment.
Heating and hot water loads are 4.19 & 3.67 kWh/m2/yr with annual carbon emissions of 12.38 KgCO2/m2 (from as built BRUKL/EPC) with the unique facility earning an A+ for energy efficiency. The efficiency of the build process was also prioritised with renewable power being used on site, and the erection of the Groove mainly requiring the use of portable power and hand tools.
Stuart Deverill, VolkerFitzpatrick, commented:
“This project pushed the boundaries of what is expected in so many ways, and it is fantastic to see our environmental diligence recognised with an Outstanding BREEAM certification.”
The delivery of PEARL demonstrates the pivotal role B&K Structures played in transforming a visionary brief into a highly innovative and sustainable building. Through their expertise in both structural steel and engineered timber, B&K Structures were able to design, coordinate, and deliver a hybrid solution that balanced technical precision with environmental performance.
Their early involvement, collaborative working approach with Engenuiti and Stora Enso, and commitment to offsite manufacturing ensured that complex sequencing, tight site logistics, and strict sustainability goals were successfully achieved.