Ten Degrees

For Tide, Vision, HTA & Greystar / Henderson Park the main objective of Ten Degrees was to deliver well-designed, quality homes, faster, safer and more sustainably. One of world’s tallest modular building, the scheme has become a beacon for offsite technology and an exemplar of innovative modular housing, showcasing the best of British design, engineering and offsite technology.

Ten Degrees is the seventh project HTA has worked on with Tide and Vision and the second build to rent project it delivered with Greystar. This collaboration between the developer, manufacturer and our architects, landscape architects, planners, and interior designers benefitted from knowledge gained from prior collaboration making Ten Degrees a culmination of this process.

The layout of the typical floor has two cores each, with 7 apartments per floor. We used our experience of these building types to maximise living space and views while minimising circulation spaces. Each home enjoys a full height windows and juliette balconies with the majority of living spaces dual aspect.

The faceted geometries of the building emerged from an appreciation of the mid-century neighbours including Richard Seifert’s No 1 Croydon. The detail of each elevations varies the rotation of facade panels and depth of framing elements by orientation to control privacy and solar shading. The resulting subtle shifts in relief across the building are complimented by a glazed terracotta cladding which fold at varying scales. Their combined effect produces a jewel like skin rich in relief.

HTA has long championed the capacity of modular construction to deliver better housing in measurably more sustainable buildings. This project is a clear demonstration that building tall can be beautiful, while challenging any perception that modern methods of construction need be a limit on design quality. Ten Degrees defines a new benchmark in the potential of modular construction to deliver more, better-designed homes, in buildings of the highest architectural quality with world-leading engineering.

Realising a building of this scale and quality in 28 months from concept to delivery required innovation in every aspect of the design and construction from the extensive use of virtual reality and 3D printing for rapid prototyping, through to exploring the geometry of the angled modular facade to create the large format glazed terracotta diamond cladding.

A concern with a building of this height was that the cores would have a tendency to sway under heavy wind loads and this would pull apart the lower module levels whilst they were under construction. To counteract this, cores were tied together in three locations up the building. A technical challenge resulting from this decision was that the lifting beam for the modules was redesigned so that modules near and under the ties could be suspended from the crane off centre, enabling them to be manoeuvred into place. The construction team averaged around 50 module installations a week, completing this phase in 28 months.

Each module has a unique structural design for its location within the building, allowing for a highly efficient superstructure with the steel frame tapering in size from 300mm square sections at the base of the tower to 150mm sections at the top on a floor by floor basis. This efficiency results in a 6% gross to net gain and a floor to floor height which is around 200m less than traditional construction making the most efficient use of materials.

A key challenge on the build came from the fact that, at 44 storeys, it was not possible to use a free-standing tower crane capable of lifting the module weights the vertical distance required. In response, an elaborate sequence of crane erection was devised by the design team. Initially a self-erecting crane was installed and tied to one of the cores. This then installed cranes onto each core before it was de-mounted and removed for the duration of the job. Towards the latter part of the project, the taller core crane removed the lower core crane and the self-erecting tower crane returned to remove the taller core crane.

The design seamlessly integrates into Croydon’s skyline by drawing on inspiration from the nearby 50p building. The facade plays on folds, shades and shadows, with repeating manufactured components inspired by mid-century traditions Mosaic tiles on nearby buildings. The deep green colour of the marble cladding on Fairfield Halls provided further inspiration. However, Ten Degrees is distinct from its neighbours and their concrete legacy. Angular, glazed terracotta panels reflect light and colour, changing through each day.

The 0.25ha site is located directly opposite East Croydon station which has the highest levels of connectivity by public transport with London Bridge and Gatwick both only 15 minutes away. Leveraging this connectivity to enrich Croydon’s town centre is a pivotal factor in the decision to facilitate ‘super-density’ development, reaching approximately 2,500 homes per hectare in the area

Terracotta was selected for the facade due to its wide variety of colours, textures and glazes as well as customization possibilities result in unique façade solutions. HTA worked closely with the specialist subcontractor (Century Facades) and manufacturer of the terracotta (NBK) to develop a glaze that echoed the marble of Fairfield Hall. A particular innovation was the large format glazed terracotta tiles used on the tower that fronts George Street.

44 storey tower

The facade panels have a more angled plan form which emphasises their verticality. The juliettes at intermediate floors are glass to reinforce the rhythm of double height bays.

The double height bays feature a more vertical emphasis with folded and ridged form of the terracotta creating a series of vertical shadow lines up the facade.

The ridged form creates an interesting effect in the terracotta with pools of the glaze forming over the low points and exaggerating the variation in colour and reflectance that naturally occurs over a panel.

38 storey tower

These facade panels use a folded triangulate panel that echoes the mid-century modern examples from around Croydon and beyond.

The angled form and variation in reveal of the terracotta will catch the light differently depending on the time of day and weather.

At the crown of the building the geometry of the plan changes from angled to orthogonal to the rest of the plan and this is combined with the omission of the framing elements to create a distinctive finale to the building.

At street level, a green garden arcade is nestled beneath a glass pyramid, to embellish the entrance at the south side of George Street. This arcade serves as the gateway to the broader regeneration of the Fairfield Masterplan, giving rise to Croydon’s emerging ‘Cultural Quarter.’ The arcade forms an impressive main entrance and is supported by a colonnade of large format GRC combined with glazed pressed terracotta tiles. To create this active frontage the base design extends around the full ground floor of the building. The uses within the building support the cultural ambitions for the area by including a restaurant, cafe and flexible spaces that can support small retail and studios. Our neighbouring College Road development will further improve connectivity on the south side with a new pedestrian footbridge planned for the Fair Fields public realm.

The public and communal landscape space at Ten Degrees were carefully conceived and crafted to strike a balance between delivering public benefits, rich communal amenity and environmental gains.

The Podium Garden sits at Mezzanine on the south side of the site. The residents can access it via steps through the Lobby.

A series of spaces created by planting offer different experiences for the residents. Benches by the water feature, a sitting area around the fire pit and a long table for working, dining and socialising will create a pleasant roof garden with views to the street and the pedestrian walkway.

The lawn area is a flexible multi-use space for relaxation, sun bathing and potentially for outdoor activities like yoga or pilates classes.

Ten Degrees plays a pivotal role in marking East Croydon Station and a public realm gateway, with a landscape design to accommodate large numbers of cycle and pedestrian commuters moving north to south. The eastern public realm accommodates commuter flow whilst delivering 13 new hornbeam ‘Frans Fontaine’ trees, a popular cultivar of the native hornbeam, establishing previously absent canopy cover and an ecological stepping stone across the site.

Faunal migration is also encouraged to the building’s west where a mix of native and flowering shrubs, climbers and trees provide a linear green infrastructure link between George Street and College Road.

Tree pits within the public realm were carefully design and delivered to connect trees to one-another and maximise soil volume, allowing trees to establish and thrive.

Ten Degrees has been designed to prioritise a passive approach to heating and cooling. 50% of the homes are dual aspect and all flats have openable windows to allow for natural cooling and ventilation. The internal layout has been optimised to ensure every home enables the largest possible number of rooms to benefit from solar gain and natural light.

The composition of the facade and windows has been carefully designed to balance the proportion of solid wall to glazed area. Overall, glazing cover is set at 35%. Excessive solar gain is also controlled by careful detailing of the terracotta facade panels, the depth, angle and orientation of which has been adjusted across the towers to deflect excessive heat and light.

Ten Degrees shows the potential of modular construction to radically reduce the carbon footprint of new homes.

Embodied carbon, which is the CO2 produced during the design, construction and decommissioning phases of a development, is dramatically lower when modular systems are used because the resulting buildings require a smaller volume of carbon-intensive products such as concrete and steel.

Due to its modular construction, Ten Degrees achieves a 40% reduction in embodied carbon compared to more traditional approaches. This is because this way of building reduces material waste, as the modular units are produced in a factory where surplus material can be controlled and more easily re-appropriated than it would be on site.

The ‘factory built’ process for Ten Degrees gave us strict control of the project allowing us to monitor key metrics. We know that this approach to construction enabled the following achievements:

• 86% reduction in vehicular movement to and from and on-site, with the related benefit of reducing noise, dust and transport related carbon emissions.
• 86 % reduction in on-site construction waste, allowing us to divert 99% of construction waste from landfill.
• 97% of factory waste was recycled.
• C02 emissions were reduced by 41%

The factory-made approach also contributes to solving issues of airtightness, thermal bridging, and quality of the finishes that can be applied to the interior of the homes. Thanks to the efficiency of a production line process construction challenges can also be more effectively resolved by working with the specialist skills of the modular manufacturer to resolve technical problems during design, reducing the number of issues that arise on site, which often cause delays to the build programme and escalating costs.

It has high fabric efficiency, good air tightness levels. Rigorous detailing reduces the air permeability of the building. The air permeability is predicted to be 5 m3 / m2 at 50 PA improving upon the rate set by the Part L Building Regulations. The scheme achieves 43 kWk/m2/yr in regulated energy. Tried and tested construction details were adopted to mimimise the occurrence and impact of thermal bridging.

Onsite renewable energy generation is provided through roof mounted photovoltaic panels that contribute to the CO2 reductions per the London Plan.

To prove our commitment to quality and gain the confidence of Planning Officers, our Architecture team worked with Tide and Vision to build three one-to-one bay mock-ups demonstrating the quality of the homes that would be delivered. This active testing formed part of the condition of the discharge process.

Regular meetings with officers continued throughout the rapid construction programme ensuring that the original vision our team had shared for the building was achieved

A key aspect of the planning dialogue was balancing what was technically possible against their impact on townscape and microclimate. Particularly important was the height difference of the two towers and the consequences this had for wind loading, with differences of greater than six to eight storeys creating a structure that would have become unviable. Working through a range of views, wind tunnel testing and daylight assessments in parallel with the structural calculations allowed a structural solution to be finalised as part of the planning process and, as a result, the two intersecting towers are joined structurally.

Recent construction in Croydon means the town has regained its earlier ambition, but Ten Degrees is considerably taller than most of its neighbours. Our Planning team balanced what was technically possible against the potential impact on townscape and microclimate. Much of the dialogue with planners focused on how we could set a precedent for other tall buildings in the pipeline, and gain consent to build on other sites that had been subject to unsuccessful planning applications?

The design is largely influenced by the modernist period with key materials and furniture pieces selected for their particular style reflecting the overall brand. There are touches of brass, lots of timber and a deep teal colour used throughout to keep the base palette consistent throughout the building but giving scope and variety for each individual space to develop.

Our role, alongside our architectural team is to design all communal and amenity spaces, maximising usage for residents and staff. Our mid-century inspired interior has touches of vintage, mixed with classic comfortable pieces for residents to enjoy. There is a lightness to the spaces, maximising the double heights where possible and celebrating the views from the worlds’ tallest modular building.

Spaces are considered and set out based on resident use and requirements with a full range of leisure provided in both towers.

At the top of the towers the residents can enjoy spectacular views from a range of shared facilities including a gym, yoga room, games room, residents lounge, screening room and entertaining room with show kitchen. Other facilities within the building include full concierge services, co-working facilities including meeting spaces and even a dog wash room. The tops of both towers enjoy access to roof terraces with the taller terrace providing a panoramic walkway offering 360 degree views across London.

We completed designing the amenity space on the ground floor, first floor, 37th and 43rd floors including the provision of co-working space, resident lounges, meeting rooms, a gym with weights and yoga room, a screening room, games room, private dining and resident roof terraces.