BREEAM rating of Outstanding for a regeneration project by Prologis

Prologis Park Dunstable, Boscombe Road involved regenerating an urban brownfield site and bringing new employment opportunities to Dunstable.  DC1, the first building on the site, is a distribution centre that was constructed speculatively by Prologis.

The success criteria for this project were quite demanding. The regeneration project needed to include:

• A warehouse unit of approximately 285,076 sqft (26,484m²) gross internal area (GIA) and minimum clear height to underside of haunch of 12.5m

• Internal three-storey offices of approximately 20,745 sqft (1,926m²) GIA

• Two storey hub office totalling approximately 4,004 sqft (372m²) GIA

• A gatehouse

• 28 dock levellers along one side of the warehouse unit, managed by a purpose-built goods in/out office

In line with the company’s global commitment to sustainability, all new Prologis buildings in the UK are designed and constructed to be environmentally sustainable.

BREEAM certification is a key metric that Prologis uses for measuring the environmental performance of its developments and was a requirement from the start of the development. Along with BREEAM certification, the other metrics that Prologis uses are:

• Reduced operational carbon emissions, which in the case of DC1 is demonstrated by an EPC rating of A (12) and a reduction in emissions of 45% compared to the 2011 Building Regulations, and

• The mitigation of embodied carbon through the ‘Planet Mark’ process.

Key green features of this project

DC1 was designed to go ‘beyond compliance’ in all areas, achieving significant improvements over building regulations in terms of energy efficiency. The building was designed to include passive measures that will reduce the demand for energy.  These included:

• High levels of air tightness (less than 1.5m³/hr/m² @ 50kPa was achieved) and insulation to improve thermal efficiency

• Rooflights to 15% of the warehouse roof area and narrow plan dual aspect offices to maximise the availability of natural light

• Brise Soleil to office elevations to reduce solar gain and improve thermal comfort

• Where energy use is essential, Prologis has specified energy-efficient systems that contribute to the project’s operational emissions reduction target

• Energy-efficient lighting throughout the development with movement controls, daylight sensing and dimming to make use of natural light wherever possible

• LED external lighting in yards and car parks

• Office heating via air source heat pumps with full heat recovery capable of seasonal efficiencies in excess of 5:1

• A 12,000 litre rainwater harvesting system providing water for non-potable use and a mains water leak detection system

• Mechanical ventilation with heat recovery via cross flow plate heat exchangers to 60% efficiencies, low specific fan power and inverter driven motor controls

The design team also looked for ways of incorporating viable low or zero carbon technologies into the building. These included:

• A 60kWP rooftop photo-voltaic array. This has been designed to offset the base energy load for the building and can be expanded to meet the occupier’s specific energy demands

• A SolarWall® ‘passive solar collector’, which not only provides pre-heated air to office areas, but also improves indoor air quality

• A rooftop solar thermal system, which has been installed to provide a renewable source of hot water for office occupants

Finally, the project team worked hard to deliver the development in a sustainable manner, achieving the following highlights:

• A score of 42 under the Considerate Constructors Scheme and full BREEAM credits in all site management sections

• 97% of demolition waste was diverted from landfill either for re-use or recycled. 100% of high grade aggregate (some 23,000m³) was sourced from the site

• The ecology of the site was assessed, monitored and enhanced under the guidance of an ecologist and exceeds the optimum BREEAM benchmarks for ecological enhancement

• The entire building envelope is constructed from Green Guide A or A+ rated materials

The project scored well across the board

• Management: 95%

• Energy: 81% (For the use of SolarWall® and a photo-voltaic array helps to reduce carbon emissions substantially.)

• Water: 100% (All practicable efforts possible were taken to reduce water waste.)

• Waste: 100% (The building was designed to generate a low amount of waste during the construction process. Also, the contractor made a commitment to ensure that waste was minimised/recycled wherever possible.)

• Pollution: 100% (All sources of pollution were designed out of the project.)

• Land use and Ecology: 70% (The development is regenerating a low value brownfield site. Construction work was carefully co-ordinated to avoid any impact on adjacent trees.)

Overall, this project shows that high-quality sustainable buildings can be delivered without significant additional cost when developers, designers, contractors and specialist suppliers work together toward clear and mutually beneficial sustainability goals, which were established at the outset.

The building, which has been constructed on a brownfield site, has been welcomed as an important part of Central Bedfordshire Council’s overall plan to regenerate Dunstable and has the potential to bring around 550 jobs to the town. From the outset of the project Prologis engaged with the Council and with local residents to ensure that the proposed buildings were delivered in an environmentally sensitive manner, which minimised construction and long term operational impacts.

This engagement influenced: the layout of Prologis Park Dunstable to minimise noise breakout; the overall building height; colour treatment of the building’s roof and cladding to minimise visual impact; and the landscape design of screening bunding on the eastern boundary to minimise visual impact whilst incorporating residents’ feedback.

Occupiers will enjoy reduced energy costs and associated emissions throughout the life of the building and as a result of the Planet Mark certification programme Prologis has helped to protect 244 acres of rainforest, mitigating the immediate environmental impacts of the development.

Reflecting on the success of the project, Martin Cooper, Director Project Management at Prologis UK, shared, “DC1 Prologis Park Dunstable is a great example of the sustainable distribution buildings that we can provide for customers in the UK. With this building we have cut carbon emissions by 45% in comparison to the 2011 Building Regulations offering the customer a similar level of energy cost savings.”

He continued, “We have achieved this by following our established sustainability strategy, which is based on three key metrics – BREEAM certification, reduction of operational CO₂ emissions and embodied carbon mitigation. BREEAM certification is a key component of this strategy, providing an externally benchmarked, understandable and transparent overview of the development process and the building’s sustainable features.”