Ruth Slavid reports on how Buckley Gray Yeoman successfully pursued the most sustainable option for a real estate client in Canary Wharf – reusing one of the site’s original offices with a BREEAM Outstanding refurb, enhanced by some striking cladding.
Forget low embodied energy materials. Forget designing to minimise energy consumption. Actually, don’t forget either of these, as they are really important. But they are outweighed by the biggest way to reduce carbon emissions when designing a new building: not demolishing the building that you already have.
This kind of preservation and reuse is a field in which architect Buckley Gray Yeoman has specialised, but when the practice first started looking – before the pandemic – at one of the earliest and most dominant buildings in Canary Wharf, this conservation approach was not common. Nevertheless, says Adam Wood, associate director, “there was nothing wrong with the original structure; we always planned to re-use it.” In the process of doing a “due diligence” for the client he says that while they “knew there was a climate emergency,” the approach of reuse seemed unorthodox, and “people were surprised.” Buckley Gray Yeoman’s determination, however, won out, and has been more than vindicated.
The building was originally called 30 South Colonnade. Designed by architect KPF and completed in 1991, it was best known for the ‘ticker-tape’ LED display of stock prices that appeared on the facade. Although structurally sound, the building was very much of its time – inward facing, with a tired stone facade and an environmental performance that was not suited to the second quarter of the 21st century. Buckley Gray Yeoman has transformed the building for clients Quadrant Estates and Oaktree, creating extra floors, and a far more open feeling. It has achieved BREEAM Outstanding, as well as meeting other important standards. The new, distinctive cladding, forming interlocking ‘Y’-shaped ogees at top and bottom, has even gifted the building its new name – the YY building.
Unlocking the fortress
Arranged around a central atrium, the original building was, says Wood, “very fortress like – it did not connect with Canary Wharf, with the wider estate, or with London as a whole.” Indeed, it was built at a time when the main public transport into the area was via the Docklands Light Railway. Getting to and from Canary Wharf Station on the Jubilee Line extension, which was built subsequently, and to the even later Elizabeth Line, was clunky and inconvenient. And it didn’t satisfy today’s workplace needs. The contemporary workplace now created is far more collaborative than what the building offered in the 1990s, with a greater emphasis on wellness – including access to daylight. If companies are to attract the best people, says Wood, “they need to offer the best in class.”
The shape of the building was unusual. Cantilevering over Middle Dock, and supported on a grillage of beams, it was designed with two equal, straight sides, facing north and west, and a single curved facade moving from east to south facing. The heavy stone cladding had fairly generous glazing to the mid floors on the curved facade, but was only minimally glazed above and below.
Because of the cantilever, it would not be possible to enhance the foundations, and therefore any additional space would have to be added within the load that the existing foundations could support. “Fortunately,” says Wood, “we had a full set of record drawings, unlike some smaller buildings of that period that we surveyed.” This allowed engineer Waterman to calculate exactly how much additional load the structure could support. Removing the heavy stone cladding and replacing it with a glazed curtain walling system saved enough weight that the team was able to add three more floors. Conserving the original steel structure has, the team calculates, saved 10,260 tonnes of CO2 equivalent.
Quantity & quality
The original building had an inset floor at level eight. By infilling this and much of the atrium, and extending upwards with a lightweight steel structure, the net internal floor area has increased by about 25%, to a total of 414,311 ft². This is a considerable achievement, but would count for little if the quality of that space had not also improved significantly.
That it has is apparent from the moment that one arrives at the building. Previously, there was only one way in, from Jubilee Plaza, on the south east corner. This is still an entrance, but whereas previously visitors passed through a narrow stone barrel that was almost cave-like, now they enter through the welcoming curves of one of the ogees to a colonnade that runs around the curve of the building, and then through a door in the set-back glass curtain walling. They then find themselves in the triple-height reception space. There is also another entrance to this space, from the lower south colonnade at the north-east corner of the building. This is at the level of the reception area and of the main lift core. Visitors who come in from Jubilee Plaza go up a curving staircase to reach reception.
The organic shape of this triple-height space, enhanced by large circular mirrored areas in the ceiling, is like a statement of intent for the entire building. It speaks of openness and modernity rather than pure functionality and a lack of generosity. A timber-clad wall shows the commitment to natural materials and a tree at the lowest level is a first indication of the commitment to plants and to nature.
Green growth
This is not just any old tree. It is an 8.5 metre high Indian fig; an evergreen with dense, shiny foliage, a grey trunk and visible roots. Buckley Gray Yeoman chose the tree in consultation with a tree specialist employed by Townshend Landscape Architects. There is a great determination for it to have a long successful life as a key part of the overall building – as Wood says: “It is not just for the photos.” He is delighted it is producing new shoots, thanks to the advice and continued involvement of Townshend. The tree is set on a rotating base, so that every three or four months it can move by a quarter turn; meaning it will not distort by growing towards the light. Daylight lamps augment the sunlight, and moisture monitors in the soil help inform the watering regime.
While the steel frame is the most significant element that has been preserved, it is not the only one. The team managed to retain four of the six original lift shafts, adding new ones at either end, and kept some of the secondary stairs as well. The cladding, however, which forms much of the public face of the building, is entirely new.
Fully glazed, it greatly increases the amount of light that comes into the building, while reducing the air permeability. High-performance solar coatings reduce the potential for solar gain. Unusually for a building of this type, the curtain walling peels back for four bays on the side facing the dock. At this point there are inset balconies, allowing access to fresh air at every level. Planting on these balconies, cascading down the facade, brings more green into the building.
The most generous planting, however, is on the top floor, at level 14. A 4,500 ft² landscaped terrace on the south and east side shares the space with the top of the three-level plant room. It has been planted with species that will offer year-round greenery and provide support for bees and other pollinators. Overall, the planting has been designed to appeal to both the visual and the olfactory senses. It includes mature trees that will provide shelter both for office workers and for wildlife. This terrace is accessible to all users of the building. In addition, there is a 1300 ft² communal rooftop pavilion which will be usable in all weathers.
Facades
Like many successful ideas, the evolution of the cladding form (the distinctive ‘YY’ ogees) was relatively simple. The architects started with vertical elements that work with the existing structural grid of 6 and 9 metres. They then interspersed a finer set of verticals on the office floors, offsetting this at the very top, and defining a clear hierarchy for the building of base, middle and top.
Finally the designers added the ‘twist’ – diagonal members joining the broader grid of the base to the finer office grid, and more diagonal members at high level joining the offset vertical elements of middle and top. In this way the architect created the distinctive ogees, which are larger at the base than at the top of the building.
At the base of the building are retail units, which will be accessible through the reception area. The rest of the space is occupied by offices, which can be let as whole or partial floors. Revolut, a digital bank founded in 2015, has taken the top four floors.
The existing floors have a 4 metre floor to ceiling height. The base fit-out includes raised access floors and suspended ceilings, with a tartan grid. Services are supplied through the ceilings. The new floors, where there is more flexibility, have exposed ceilings. The tallest floor-to-ceiling height is 5 metres.
Even with its additions, the building is by no means one of the tallest in the Canary Wharf development but its position, overlooking water, means that it can never be boxed in and therefore will remain dominant and not overlooked.
Environment
In addition to the savings in embodied carbon, and the savings that result from the improved performance of the curtain walling, there is a strong environmental strategy running throughout the building. It is all-electric, with rooftop photovoltaic panels and air-source heat pumps providing heating and cooling. Waste heat is re-used. There is no greywater recycling within the building, although it was considered; Wood explained that there was no room within the existing floor to ceiling heights for the necessary services.
Materials, wherever possible, were sourced sustainably and in a form that will allow them to be recycled. The architect looked at the possibility of re-using the old cladding in some form, especially as it was panellised and mounted on a precast concrete facade which meant that removing it was relatively easy. But Wood explains that, although the team looked at re-using some of the stone within the terazzo floor in reception, this proved to be impractical. Because the stone was bonded to the concrete panels, it would have needed to be crushed and used as the base. At the time, this process could only have been carried out in Italy, which would have meant shipping the heavy panels there and then bringing back the finished material, negating the environmental savings. Wood however remarks that now, companies in the UK are doing this work.
The brief for the building was to achieve an EPC of B and BREEAM Excellent. It surpassed both of these, with an EPC of A and BREEAM Outstanding, both the highest rankings available. It is also ‘WELL Platinum-ready’ (the WELL Standard, which measures the health of buildings by seven criteria, can only be finally confirmed when the building is occupied and in full use).
The credentials don’t stop there. The building has also been rated on the Australian NABERS rating scheme which measures both the embodied and the operational carbon of a building. The original target was to go for a five-star rating which equates to excellent (the scheme goes up to six stars, which is ‘market leading’). But the target was lifted to 5.5 stars – likely to be the maximum possible within an existing building. The final rating will not become available until the building has been in use for a full year.
The building has also achieved both a WiredScore Platinum and SmartScore Platinum. There is a relationship between the two, but they are not the same thing. Both are a way to measure the building’s resilience and its use of technology to ensure smart building outcomes, and both are administered by the same organisation, WiredScore.
The difference lies in what they measure. WiredScore looks at connectivity and the resilience of systems coming into the building. It measures connectivity to mobile and internet services, the ease of connection to the internet, the ability to accommodate new and emerging technologies and resilience against outages, accidental damage, cyber attack and the impact of climate change.
SmartScore certification is a newer measure, only launched in 2021. It focuses more on the experience that the building can offer users. Highly scoring buildings give users a great experience, with flexible and personalised services. They have a reduced whole-life carbon footprint, use technology to operate the building more efficiently and are resilient, being able to accommodate changes that are both expected and unknown.
One important way in which the building satisfies these criteria is through the use of a digital twin, which updates and models every element of the building’s operation, from lighting control to indoor air quality and occupancy analytics. There is also a special app designed for the building’s users.
Although the project spanned the Covid pandemic, with the first appointment made in April 2019, and practical completion in July 2023, the final account only exceeded the contract sum of £135m by £600,000. This was, the team believes, in large part due to directly letting several key subcontracts: the facade, structural steel, MEP, lifts and the reception desk. The client was able to do this on a design and build basis because Buckley Gray Yeoman provided early specifications and drawings in advance of RIBA design stage 4. The biggest saving in both total and percentage terms was on the facade, where a saving of between £5 and £8m represented a 30% reduction in cost.
In touch with history
Almost all the shortcomings of the original building have been eliminated, so that casual observers would see an entirely new building, and one built to the most demanding of contemporary standards. But Canary Wharf, despite its relevant youth as a development ‘cluster,’ has its own history – and the designers have paid tribute to that built legacy.
The eye-catching ticker tape screen around the outside of the original building is now referenced from within reception in the form of a high-level array of LED lights in a strip around the area. These can convey words or images, as required. Woods says this ‘digital art wall’ can show a pattern of water, of trees or of clouds. In contrast to the previous more mundane communication of stock market prices, it enhances the building’s connection with nature.
There’s another piece of development context to the project which is a fortuitous alignment with its nature focus. Canary Wharf Partnership has renamed the Middle Dock as Eden Dock, in reference to the Eden Project, transforming it to create a place for nature and biodiversity within an intensely developed business area. There is a well-established concept of ‘borrowed landscape’ – buildings which benefit from their surroundings. In the case of the YY Building this is purely serendipitous – but given all the deliberate steps that have been taken to improve the quality of the original the serendipity seems well-deserved. What could benefit more from an improved setting, than a building that has conserved its frame, extended and turned itself into a pleasant, welcoming, healthy and environmentally responsible place in which to work?