Hartree

Hartree will be a transformative, sustainable, inclusive, and affordable community – a distinctive place where a population of over 11,000 will shop locally and put down roots and be a part of their neighbourhood. The project is the last large strategic brownfield site in the emerging district of Northeast Cambridge, which aims to create a sustainable economic and employment ecosystem, fuelling jobs, business growth and innovation. A bespoke and practical Sustainability & Quality of Life Framework guided decision-making processes to ensure aspirational targets were measurable and deliverable.

Kjellander Sjöberg was appointed to lead the masterplan process and to develop the vision to outline planning stage in a tight client collaboration with regeneration specialist LandsecU+I and profit-with-purpose developer TOWN. The project was a joint venture with landowners Cambridge City Council and Anglian Water.

Illustrated masterplan of Hartree. A new liveable, walkable and low-car urban quarter with 5600 homes, two schools, shops and community services.

A new urban quarter with three promises

Hartree’s Promises & Values embody the spirit of Hartree, guiding the project through its briefing, design, and development stages. They are central to the Sustainability & Quality of Life Framework and are reflected in our Design Principles.

Aerial image of Hartree looking north. Secchi Smith & Kjellander Sjöberg

A place that is inclusive, sustainable, and anchored to its unique heritage and the adjacent Fen landscape.

Landscape map showing the river and Fen landscape which are defining features of Cambridge. Image: LOLA Landscape Architects

In and of Cambridge – local context

Cambridge’s existing green and blue network is a character defining feature of the city, linking urban areas to its broader farming and country landscape. The North-east [AW1] Cambridge area is driven by a focus on education, innovation, and employment.

Today the site functions as the Anglian Water Waste Water Treatment Facility and is located just a 20-minute cycle or bus ride from central Cambridge. Only a 10-minute walk from Cambridge North Station, the location offers sub-hour train services to London.

Drawing showing the Post Room; an existing Victorian building which can be found on site today. These and others have been integrated into key areas of public realm within the masterplan.

Using what's already there

Hartree is currently a complex brownfield site with significant industrial constructions and in possession of several key landscape structures that enhance its ecological value, including eco-corridors along the edges of the site.

While some pose challenging contexts to increase permeability, others provide opportunities to rebuild streetscapes that integrate the new development into a broader more cohesive urban fabric.

Site photo, LOLA - showing an existing boundary condition including 'first drain' water course.
Site photo, LOLA - showing an existing water filtration tank.
Site photo LOLA - showing an existing concrete structure within the site area.

What sounds so simple will revolutionise how we build towns forever.

An early axonometric drawing exploring a possible combination of buildings, parks, schools, streets and courtyards.

More than just homes

Hartree is a low-car, low emission, residential-led mixed-use quarter of 5600 homes. Driven by the 5min neighbourhood model, Hartree will provide residents with two new primary schools, a library, community centres, a medical hub, shops, local sports facilities, recycling centres, last mile logistics and over 6000 jobs.

Hartree presents a unique opportunity to positively impact the long-term health and well-being of its residents as Cambridge’s newest and most forward-looking neighbourhood, embodying a vision of health, accessibility, sustainability, and community.

Diagram showing the three neighbourhoods, with 5-minute walking radius marked as well as the central neighbourhood squares and Playline park along the diagonal.

Three 5-minute neighbourhoods

Hartree’s three neighbourhoods each provide a unique mix of community and retail uses, employment spaces, and housing options. The distinctiveness created by selectively clustering land uses promotes a flexible, inclusive spatial economy, ready to adapt to future everyday errands and are situated close to homes and integrated into an active travel network.

Image of Cowley Square within the North-west neighbourhood with retained Victorian era buildings visible to the left. Kjellander Sjöberg collaborated closely with the client team to test deliverability for a number of scenarios regarding optimising density, methods to reduce vehicular traffic, maximising access to and the amount of public open space and carefully curating mixed-use neighbourhoods.
Diagram showing the primary pedestrian and cycle routes in relation to parks, shops and community uses.

Mixing uses

To ensure Hartree will become an interesting place to be, strategic clustering of residential and non-residential uses is celebrated at building, square and neighbourhood level across the site. The three levels of clustering shape a resilient urban environment with adaptable spaces that support both micro and larger areas of public realm.

A series of diagrams showing the approach to planning the three neighbourhood squares and the central open space of the masterplan called the Playline. Medium-rise buildings provide wind protection while allowing sunlight, and varied roof heights reduce turbulence. Streets that curve and change width offer sheltered pockets, making the entire neighbourhood feel pleasant and inviting year-round.
A detailed zoom in at the 'people' scale, focusing on potential real-life occurrences within Hartree.
An axonometric showing the Main Street, which links Hartree Square in the south, to Cowley Sqaure in the north.

The Main Street

The Main Street is the most ‘civic’ street in Hartree. The southern part is more ‘town centre’ in nature with parts of the street flanked by stand-alone commercial buildings. Further north the street has a more residential character, defined predominantly by mixed-use layered buildings with more public commercial, retail or community uses at ground floor.

Meanwhile uses play a crucial role in the evolving clusters of activity within Hartree. While the illustrative scheme presents the ‘end state’ of the masterplan, flexibility in delivering core services and amenities has been intentionally built into Hartree’s civic spaces. This allows for a variety of non-residential formats to accommodate different uses in the interim, as the community develops and prepares to welcome larger, long-term tenants.

An eye level view of the Main Street looking north showing the mix of modal uses including local busses, bikes and pedestrians. Local car use has been designed out of this space to avoid rat running better air quality for shops and cafes.
An eye level view of a courtyard space, boarded with family apartments. These communal but private spaces are vital in higher density places, ensuring safe spaces for children to play and maximising dual aspect homes.
Diagram showing the spread of block types across Hartree. Each colour represents a different block type.

A variety of shapes and sizes

A key aspect of good density is balancing open and built space. With a consistent site density, the Hartree masterplan offers diverse residential and commercial types through several urban block types that achieve this balance.

A detailed axonometric showing a Pocket Park Courtyard block type.
A detailed axonometric showing a Mews Courtyard block type which has dual semi-private mews street and private courtyards.
A detailed axonometric showing a Perimeter Block Courtyard block type.
In addition to varying types of blocks, Hartree has a number of street types defined largely by the extent of access to motorised vehicles. This illustration shows a Play Street with row-housing on either side, nearly- car free routes with the remaining space given over for greenery and door-step play.
Diagrams showing the character areas of Hartree, informed largely from the sites varying boundary conditions.

Responsive Urban Form

Hartree’s urban design starts with a tailored approach to its six unique edge conditions, integrating the development into Cambridge’s urban and natural landscape. This foundation guides the neighbourhood-scale design within the site, employing a nuanced approach that considers density, microclimate, and a distinct sense of place. It is shaped to ensure high-quality, comfortable homes with outdoor spaces that encourage year-round use, incorporating weather-appropriate designs like shade, wind protection, and greenery for comfort. Together, they create a varied and diverse range of building expressions, drawing design cues from broader local examples of Cambridge’s distinctive townscape.

Many Types of Homes

Hartree will provide up to 5,600 homes designed to passive standard and delivered across a variety of tenure types and housing typologies. These include family apartments, co-housing, self or custom build, specialised housing for older people, artist and live/work homes, post grad housing, and purpose-built houses in multiple ownerships. Different home types are strategically distributed across the site and in many cases across individual blocks to ensure flexibility in the masterplan’s delivery and prevent socioeconomic zoning between neighbourhoods.

Kjellander Sjöberg led a large team of award-winning British Architects who plot tested various places across the site. The team included: Bell Phillips Architects, Haworth Tompkins, Alison Brooks Architects, Nooma Studio, Feilden Fowles, 5th Studio.

Image by Nooma Studio showing a co-housing block along with community facilities such as allotments, a common house, co-working spaces and connections to local park spaces.

Three images by Bell Phillips Architects exploring the entry spaces for apartment blocks and terraces housing. Focus was given to exemplar access to bike and pram storage, level thresholds, integrated seating and covered shaded zones.

Good Density

Hartree is designed for higher density living, focusing on creating sustainable, vibrant, and lively mixed-use environments. At a more granular scale, Cambridge’s built form is defined by layering, setbacks, stepped rooflines, closeness to nature, and strong street-level connectivity, all within a palette of predominantly brick, stone, and masonry materials.

An image showing a local street and homes that face onto the Playline, the central park. Mature trees and local grasses characterise both the urban experience and the quality of surrounding homes. Slow speed streets are activated with communal and commercial uses at ground floor.
Diagram showing the major and minor routes in Hartree relation to key destinations.

Moving Around

Hartree promotes low care usage and active travel by offering high-quality routes and transport options designed for people, set within safe and thoughtfully planned street-level environments.  The route network design connects key destinations such as schools, shops and parks, ensuring strong connectivity within the site and to surrounding pathways. By transforming the site from a cul-de-sac into a vibrant urban quarter, the route network lays the foundation for an expanded bus and cycle network.

Diagram showing the structure of the green and blue network including existing waterbodies, landscape structures and routes.

Living Landscapes

Hartree’s landscape strategy focuses on preserving as much of the existing habitats and landscape structures as possible. A diverse programme of activities for people and habitats is distributed across various types of open spaces, connecting every block to a green open space.

The new landscape network integrates with neighbouring larger landscapes, connecting walking and cycling routes and paving the way for potential future expansion into adjacent areas.

Images by LOLA highlighting key landscape structures within the masterplan. These connect private and public open spaces; each designed with a bespoke play programme and integrated water retention assets.

The Playline

The Playline, stretching 670m diagonally and incorporating the 2.9-hectare Central Park at its centre, forms Hartree’s largest open space. It offers extensive areas for the community, including children, teenagers, and informal sports. It connects the two primary schools at each end, with local community services and homes in a car-free environment.  The adjacent frontages shape a series of interconnected green “rooms” that can be experienced either as a whole along the central axis or individually, shaped by the ground floor activities at the edges.

Zoomed-in aerial CGI image by Kjellander Sjöberg and Secchi Smith showing details of the Playline.
Nearly eye-level view looking east through the Playline. Image by Kjellander Sjöberg with Secchi Smith.
City People Planet Festival
Workshop for Young people
Engagement Exhibitions
The design encompasses six design principles.

Shaped by Many

A detailed engagement programme was curated for Hartree, through a wide range of in-person and online forums that included formats such as citizen exchange, festivals, post occupancy surveys, roadshows and young people workshops.

A key element of engagement was the ‘Ideas Exchange’ which consisted of a cross section of Cambridge residents unaffiliated with any specific group or forum. Meeting consistently over the term of the project, it was a platform to discuss the project’s emerging work through a series of conversations held over several years.

Making a unique and special new place in Cambridge requires a bespoke and collaborative team. As the Masterplan Lead, Kjellander Sjöberg headed an exceptional team of creative practices and technical consultants, each bringing expertise to the project. The wider team includes sustainability strategists Useful Projects, E.C.F communication & engagement, Pell Frischmann engineering, Urban Movement transport & mobility and Live Work- service designers tasked with unpacking the challenges analogous to building robust and adaptable communities.

Design Quality

A Design Code, along with a set of Parameter Plans and a Design and Access Statement, was prepared by Kjellander Sjöberg for formal approval by the local planning authority. The Design Code outlines approved rules and requirements for the detailed design of Hartree, to be delivered throughout later phases. These documents ensure the delivery of a high-quality neighbourhood that reflects the vision, aspirations, and values of Hartree.