The construction of the new Student Centre had to balance high-quality design that was sympathetic to the sensitive Bloomsbury conservation area, whilst also pushing the boundaries of sustainable development on a constrained urban site. The goal of this new building was to help to alleviate pressures on existing study space, whilst also enhancing the student experience by being responsive to future change, with flexible spaces and integrated technology.

The project team had to demonstrate a consistent and driven commitment to UCL’s core objectives – including the pursuit of an Outstanding rating – all to ensure this scheme is seen as a true exemplar within the higher education sector.

UCL committed the resource and expertise required for such aims, with no less than three sustainability champions working seamlessly alongside the design team and the contractor. This rigour resulted in coordinated, detailed scrutiny of the requirements of individual credits, always with an eye to maintaining or increasing the score whilst providing demonstrable value benefits.

Energy strategy

The building’s energy strategy was aligned with BREEAM Ene 01, which included a ‘Passive first’ approach to design, based on highly efficient building fabric and use of thermal mass. All of which helps to regulate temperature, minimise energy use and corresponding levels of detailing.

In typical winter and summer conditions, displacement ventilation fed from a modest raised floor zone, will provide fresh air which is extracted through the atrium at high level. Supply air is tempered by either free cooling from the GSHP or by free heat recovered from the extracted air (MVHR) resulting in reducing energy bills for UCL and improving the environment for the Students.

The building is projected to achieve a 35% reduction in building carbon emissions against Building Regulations requirements (Part L 2013) and 40% improvement on Part L 2010. Design stage modelling indicates a minimum 20% reduction in building CO2 emissions, achieving all five credits for low and zero carbon technologies (Ene 04) – this is based on:

1. ’Free’ cooling will be provided, using an open loop ground source borehole system connected to cooling pipes embedded in the underside of the floor slabs and cooling coils in the AHUs. Heat pumps use the borehole for low grade heat regeneration.

2. Connection to UCL’s District Heat Network.

3. The 50KWP PV array (around 400m2) is UCL’s largest installation to date, extending to the roof of the neighbouring Bloomsbury Theatre.

Optimising the working environment

Another area of particular importance to UCL was optimising the working environment in order to improve health and productivity. This included a mixed mode strategy with automatic window actuators will naturally ventilate the building in the spring and autumn preventing overheating while eliminating the need for mechanical ventilation and reducing the requirement for active cooling (Hea 02).

A central atrium will help to draw heat up and out of the building in the summer. In the winter this waste heat will be captured and used by the AHUs to pre-heat incoming fresh air. The provision of a detailed indoor air quality plan helped to steer design decisions in an area of sensitivity given the proximity of particularly congested roads (Hea 02). This resulted in the selection of self-finished natural materials.

Visual comfort was also prioritised, using daylight modelling to optimise facades and achieve maximum penetration of natural daylight (Hea 01), whilst reducing the need for artificial light. This includes tall windows extending up to soffit-level, clerestory windows and a glazed atrium. The glazing design is responsive to orientation to minimise unwanted solar gains, creating comfortable spaces to study.

Biodiversity

The project carefully considered opportunities for improving biodiversity on this significantly constrained urban site, particularly at roof level. There areas of biodiverse roof that assist with rainwater attenuation are combined with external amenity space for users, as well as space for PVs, and rooflights. Enhancements will also have a positive influence on the microclimate and provide additional ecological value within the Bloomsbury Conservation Area.

Sustainability management

UCL’s high expectations were clearly embedded and communicated in tender documentation. They remained under constant review by the project management team, as well as the principal contractor’s Sustainability Manager (Man 02). Their responsibilities included extensive consultation with a broad range of stakeholders (Man 04) continued from the earliest design stages through construction, ensuring a shared sense of project ownership that established a firm basis for delivering the intended design objectives for the building in use. These efforts were helped by a collaborative project team approach that has served as a catalyst for delivering innovative and forward-thinking solutions. The full Soft Landings process has been adopted and followed.

The final CCS visit scored 42/50, with the site team praised by the CCS visitor, who cited “community investment is exceptional with great work already commissioned”. During the installation of the open loop ground source borehole, which uses the presence of a natural aquifer below site, the project team redesigned their processes to find a novel way to reduce water consumption. Water was drawn from the first borehole during drilling and used to break out of the second borehole in a loop that returned the water to the aquifer. This saved 203 m3 of water fit for drinking.

Life-cycle considerations

The building has been designed for a variety of current and future functions and occupiers. Flexibility and adaptability have been maximised through uninterrupted floor areas, and large floor-to-floor heights provide generous airy spaces on each floor. A regularised elevational approach allows potential internal sub-division, and the raised floor zone allows easy adjustment to services distribution. The benefits of life cycle assessments (Man 05) have proved decisive in informing decision-making during design development. The use of cross laminated timber for parts of the roof-structure is one such outcome.

Accessibility and efficiency

The Student Centre has a particularly high accessibility index, being located just off Euston Road and only a couple of minutes from Euston Station. Unsurprisingly, it therefore benefits from a wide range of local facilities. As part of the project, UCL have provided 54 new cycle parking spaces, with additional facilities due to be provided close by on the campus. The building has a number of new (water efficient) shower facilities.

Waste and water management

The contractor, Mace, reported 100% of construction waste was diverted from landfill. The team worked hard to improve material efficiency and reduce waste, especially given the challenge of a constrained site. The team excelled in this challenging situation by engaging with Social Enterprises like Community Wood Recycling. Community Wood have collected timber waste from the site and reuse it to train disadvantaged people in the local community and give them valuable skills to get into work. Using this reuse scheme has so far saved the project 14 tonnes of timber waste.

‘Design out Waste Workshops’ were regularly carried out. One of the biggest achievements to come from the workshops was the decision to change to a reusable shuttering and formwork system; this saved over 2 tonnes of timber waste being generated during the concrete pour of the basement slab and secant pile liner wall.

Efficient sanitary fittings will reduce water consumption by more than 55% based on the use of the BREEAM Wat 01 calculator, which helped to steer the team towards the most water efficient options and achieving five credits.

Resource consumption

UCL prioritised circular-economy principles in a drive to reduce resource consumption and the project has clearly addressed this area: 100% of timber was FSC certified and 100% of concrete, steel and plasterboard was certified to BES6001. Highly durable materials were selected to help minimise resource use associated with maintenance and repairs. The design team also prioritised higher Green Guide ratings to increase the score’s in relation to Mat 01 – Life Cycle Impacts.

Whilst designing the concrete mixes and investigating procurement routes, Mace realised they could exceed the initial target of secondary aggregate used in the concrete frame. The total quantity of secondary aggregate used in the frame was 1370m3 (53% the total volume of aggregate). This resulted in 2465m3 of waste products being included in the final building (Wst 02). The design also included Ground Granulated Blast-furnace Slag (GGBS) as the primary cement replacement in concrete mixes.

In the structural frame and floor slabs, 50% of the cement was replaced with GGBS, meaning the carbon footprint of the concrete in the frame and slabs was halved from 913kgCO2e/tonne to 457kgCO2e/tonne. This is a flagship project for Mace, the lessons learnt and success of using secondary aggregate in the mixes plus the tangible benefits have led to Mace incorporating the use of secondary aggregates more widely into their ‘Responsible Business 2022’ strategy.

Key achievements included:

• ‘Passive first’ approach to design based on highly efficient building fabric which helps to regulate temperature and minimise energy use. EPC A rating confirmed.

• 35% reduction in building carbon emissions compared to Building Regulations requirements (Part L 2013)

• 400m2 of solar PV panels on the roof provide clean, renewable energy

• Ground source borehole system provides both heating and cooling

• Natural ventilation strategy includes high levels of thermal mass coupled with night purge during the summer season.

• Highly efficient sanitary fittings will reduce water consumption by 55% over baseline performance

• Healthy and productive study spaces, optimising daylight, indoor air quality and providing a comfortable internal climate

• Highly durable materials will help to minimise resource use associated with maintenance and repairs

• Biodiversity enhancements include planting in the adjacent Japanese Garden and a green roof which will also have a positive influence on the microclimate

Looking to the future and reflecting on the longterm commitment to BREEAM standards, Anthony Smith, Vice-Provost of Education and Student Affairs shared, “BREEAM provides a robust and well-understood framework for the implementation of sustainability on the UCL estate in support of our 20-year development strategy, ‘UCL 2034’. It also complements the university’s Sustainability Strategy, as well as our ambitious Carbon Management Plan and Sustainable Building Standard. This is reflected in support for achieving the highest possible ratings from UCL’s senior management team.”