Shared opportunity

James Parker reports on how Assael Architecture achieved a pioneering co-living scheme which used a difficult site to the full to give single occupants and keyworkers a foothold in London, plus co-working and shared amenities to combat loneliness

Sunday Mills, in Wandsworth, south west London, is a new iteration of the co-living concept which brings the benefits of shared facilities to the fore, and resolves a site which was a long-running conundrum. Completed in October 2022, this is the first large-scale co-living project in the Borough, providing 315 self-contained studios powered completely by low-carbon technologies. But it also has a 35% allocation of studios allocated as locally ‘affordable,” targeted at keyworkers and young people leaving foster care in particular, giving them a rare opportunity to live closer to the centre of the capital and their workplaces, in high-quality homes.

Innovating in a use class which was lacking specific planning policies, Assael Architecture were commissioned to provide a scheme with an unusually high proportion of social and shared spaces and areas, to give residents a variety of ways to interact. Ranging from a roof terrace to a voluminous co-working space and shared kitchen, they were envisioned to create a new type of apartment block that would help avoid the isolation many renters can experience in the metropolis. 

The project is operated by Folk, an arm of Manchester-based Build to Rent operator Urban Bubble, and it’s their second co-living scheme in the capital, the first being completed in Harrow in 2022. The developer clients were co-living fund, DTZi, and developer Halycon, who took over the project following the demise of co-living specialist developer The Collective in 2021. A casualty of the pandemic, they had initially engaged Assael to develop a feasibility study for the project in July 2018. The architect had been involved with reviewing options for the site on previous occasions for more traditional residential use, but the constrained, triangular plot, plus flood risk, previous industrial use and access issues – not to mention a nearby travellers’ site – meant it was not pursued.

Fast forward to 2024 and now this relatively quiet suburban corner of south west London – where a Thames tributary (the River Wandle, once described as the ‘hardest working river in London’) crosses the railway line east of Wimbledon Park, now contains an important housing milestone. The brownfield site was previously occupied by stacked shipping containers, but had virtually none of the history of textile, paper and tobacco industry visible, instead there was a brick built shed plus asbestos roof. It is bound to the north and west by a Network Rail ‘eco corridor’, the river to the east, and a recycling plant to the south.

Sunday Mills has a relatively large quotient of affordable studios, with 110 (35% provided at discounted rents, something later co-living schemes will not be able to offer given recent London Plan policy. Starting at only £182 per week, a key part of the development’s success is that enables workers who have found it impossible to live in London, to be located 20 minutes from Oxford Circus.

The architects looked to make the most of the riverside setting, and to maximise local connections, adding a new pedestrian bridge to neighbouring Earlsfield, but also making some of the shared spaces within the project flexible for community use. The scheme also includes the extension of the Wandle Trail cycle route into Merton, which is hoped to be created in 2025.


Discovering an absence of planning policies for the emerging concept of co-living, whereby tenants share some facilities but have their own space, the architects undertook initial pre-application meetings with the then client The Collective in 2018 to promote this as the way forward for the site. These meetings including touring The Collective’s original Old Oak co-living scheme designed by PLP. Following these discussions, a brief was established, and the scheme was submitted for planning in March 2019 and was approved at committee in July 2019.

Ed Sharland from Assael pays tribute to the client for giving them “a lot of freedom” in addressing the brief. “They trusted us, and were a progressive brand that were keen to do something a bit more interesting.”

Community engagement included a Community Investment Programme (CIP) initiated early on by The Collective and appended to the Section 106 in the approved scheme, with the aim to deliver a “shared vision” with the local community. Assael Architecture says this is “demonstrably influencing the building operation,” manifested in partnerships with community groups like a local food bank, river cleanups, a theatre company, and a centre for adults with learning disabilities. The bigger picture of 35% of tenants being local or keyworkers gives the scheme a compelling tie-in to local social value.

Procurement was by way of a single stage tender, with the contractor appointed in September 2020. Assael were novated and construction began in November 2020, and was completed in October 2022 on time and budget.

Overall design

The scheme, built using a Design & Build contract by Laing O’Rourke, was designed to “interact with and enhance” the riverside setting, say the architects, including with a new accessible pedestrian bridge connecting to the ‘Wandle Trail.’ Ground floor amenities such as the cafe and co-working spaces have been positioned prominently (the former at the glazed south east corner of the building behind dramatic, industrial-inspired steel elements), to “activate the riverfront and create a strong connection to the natural environment.”

The building responds closely to its constrained site, with two linked apartment blocks inspired by the site’s industrial heritage, designed to address the river and railway respectively. They have been carefully orientated for users’ benefit, and are connected by the double-height entrance. The cafe and restaurant provide further connection with the outside, with seating spilling out onto a terrace area enhanced by the sound of the river.

The forms have been articulated slightly to offer more visual interest externally with a more organic, ad hoc feel, and better internal environments avoiding north-facing rooms. Each of the two connected blocks have been broken down into two further forms visually, of different heights (from six storeys to eight). Associate director at Assael Emily Newton explains the approach further: “We kinked the two blocks to avoid single-aspect north-facing rooms and long continuous corridors.”

The volume facing the railway contains the kitchen (on the second floor) and connected dining space, offering different types of cuisine for both Folk’s tenants and locals to sample in the restaurant. Resident allotments on the terrace adjoining the kitchen contribute vegetables and herbs. There is a capacious roof terrace on the sixth floor, landscaped by Farrer Huley and Park Hood.

The first floor contains most of the amenity spaces, with the lounge and breakout area sitting above the central reception. Towards the east flank and overlooking the river are the library and bookable private dining room, and behind the circulation core is the ‘screening room’ with its cinema-sized screen and comfortable chairs. On the north end of the block is the ‘co-working mezzanine,’ benefitting from diffused daylight and a variety of spaces to work, and the fitness suite sits along the western flank. 

Ed Sharland says he believes the co-working space will be “used extensively by residents,” with a benefit that it enables them to “easily separate their work/life space and time,” due to it being separated from the living spaces. “We know this has been an issue since Covid, and growth in flexible working.” There’s also a plan to allow local residents to use the space.

Industrial inspiration

The buildings’ industrial-style detailing includes large dark grey metal-framed windows in the brick facades, and different red and pink brick used across the forms breaks up the facades and gives the feel of a series of buildings constructed over time, as the mills of the past often were. Also, the varied roofscapes include pitched roof gables and a lantern-style front roof, giving a feel of old industrial buildings.

The warehouse-inspired, highly regular fenestration arrangement is leavened by the splayed, chamfered forms of the window apertures, whose deep reveals provide dramatic shadows at certain times of day. Says Emily Newton: “It creates a really nice zig-zagging facade pattern.” And the external fire escape stairs are in dark grey metal, a further contributor to the proudly industrial look.

The industrial-style metalwork is a distinctive feature throughout, especially signalled by the external steel W-beams which support a section of the ‘first floor’ above the double-height glazed entrance, and add some dynamics to the overall look. There are also the vertical I-beam columns, and perforated metal balustrading, and all elements are in dark grey.

The external design language of earthy tones and unfinished surfaces, partly inspired by the river, continues in the interior, alongside notions of ‘wabi-sabi’ design (embracing “transience and imperfection”). Featuring a “pared-back material palette,” the design was undertaken by Assael’s dedicated interior design arm, Assael Interiors. Emily Newton comments that there is “always a benefit when we have that aspect in house, because we can work closely with the interiors department.”

Living spaces

The building’s single-aspect ensuite studio rooms are generally 17 m2 – plus some duplexes located within the roof spaces at 25 m2 (and 30 m2 for wheelchair users) – and all feature kitchenettes.  Ed Sharland explains the focus on single-aspect as being an essential approach to support the multi-amenity concept here: “Dual aspect co-living rooms are difficult to achieve, with the building layout they’re more like student or hotel rooms.” He continues: “On these kinds of challenging sites, you have a responsibility to include the correct amount of optimisation density to make it work; you need a critical mass within co-living to enable you to provide those shared amenity spaces and the level of management they require.”

Creating that “critical mass” of co-living spaces also helps support the community feel which is essential for this and similar projects to be a success. “Everyone who lives there is encouraged to use the
amenity spaces, and it’s very attractive to people who are lonely. One of the big positives in the planning process was the potential to combat loneliness.”

The studios have been “meticulously designed to maximise space and light,” say the architects, through a combination of “smart” integrated storage, built-in joinery and full-height, opening windows. “We pushed for these as part of the warehouse aesthetic,” says Ed Sharland, revealing there were some calls to ‘value engineer’ them towards an alternative which wouldn’t be glazed down to the lowest level. The building’s concrete frame enables exposed soffits, adding thermal mass to benefit cooling, and provides generous 2.7 metre floor to ceiling heights. 

Each studio comes with a double bed, and a Samsung TV, plus air conditioning and good storage, meaning people are able to move in without needing to furnish their home. However, beyond the pragmatic ability to live functionally in a central London site, the scheme has a variety of other key selling points which harness and support the benefits of shared living.

The building offers residents access to a range of shared amenities and communal spaces, including a gym, yoga studio, and a large, well-landscaped roof terrace with great views across London. As well as the multiple co-working areas and cafe restaurant, which are shared with locals, for relaxation the residents benefit from a cinema semi-private ‘living spaces.’ There are also a range of more private nooks around the building, such as within the central entrance hub staircase, and window seats on the first floor overlooking the river. Last but not least, there’s a fully-equipped, ‘Masterchef-style’ shared kitchen, fitted out to a professional standard, and enabling residents to cook socially together if desired, helping to increase their sense of connection and community.

This is a ‘24-hour building,’ predicated around the fact that many workers who will be tenants here will be on a variety of shift patterns. This means that the amenities will be available to tenants around the clock, making full use of the building functions, as well as creating a set of challenges for the operator such as staffing.

The development offers tenants a level of quality and finish which is comparable with that of a hotel, in the studios themselves as well as the various shared amenity spaces. For example, due to the care paid to acoustic insulation, the rooms facing the railway line are not troubled by excessive train noise. As part of the fully-serviced nature of the compact studio flats, cooling as well as heating is provided which means windows don’t have to be opened for a comfortable environment.

Ecology & sustainability

The designers took various steps to try and minimise the impact on local nature. Careful consideration was given to the lighting levels, as well as the positioning of buildings to protect nocturnal wildlife and marine life, including bats and water voles around the site and along the river corridor. The all-electric development is BREEAM Excellent and EPC A rated, and placed life cycle assessment of embodied carbon at the core of the design.

Despite not being a planning requirement at the project’s outset, The Collective commissioned a Carbon Lifecycle Assessment. An analysis of material, efficiency and cost at each design stage saw changes including reusing the majority of the existing concrete slab (for piling mat and sub-base); reduced concrete slab and floor build-up, and switching to a brick-slip system. The assessment found embodied carbon for the product and construction stages was 544 kgCO2e/m², below the LETI 2020 best practice target. Exposed concrete soffits to all studios and many amenity spaces contribute thermal mass.

A range of green spaces were created, focusing on native species. Beehives, bat boxes, bird nesting, bug hotels, and wildflower meadow planting all contribute key biodiversity. The success of these measures will be measured over the next 10 years, as well as the performance of the roof PV arrays, and the communal heat pump system. Kit is currently being installed to monitor individual energy use in studios, and architect and client are exploring ways to incentivise energy-efficient living.

Building community spirit

The building is a rare combination of affordability and quality in the heart of the capital, creating a vital chance for tenants to be able to live closer to work. It’s a testament to the co-living innovation of The Collective, a much-missed pioneer, as well as the dedication of the architects, developers and investors. Aside from the excellent facilities, the residents will benefit from ‘all-in’ rents inclusive of bills, which will help protect them from rising living costs.

Assael says a strong post-occupancy ‘feedback loop’ is giving them lessons to feed into future schemes. This includes speaking to residents and operations teams to discover what is working well, and what can be improved.

Over the six-year duration of this project, a strong relationship was established between Assael and the developer, Halcyon. They refer to Assael’s “deep commitment to deliver their design ethos and brand standards,” and say that “in the absence of clear planning standards and on a tricky and constrained site, they worked to find innovative solutions that delivered efficient yet exciting architecture.” This is one of the reasons why the building gained the local support which was critical to its success.

One of the most satisfying aspects for Assael is that their initial concept survived through to completion “virtually unscathed.” And, in the words of Nik Dyer, associate director of development at Halcyon Development Partners, Sunday Mills is a clear demonstration of how the practice can provide co-living that deliver a “real sense of community.” Here, he says, this has produced a scheme that the client is “incredibly proud” of.

Project Factfile

  • Funder: DTX Investors
  • Developer: Halcyon Development Partners
  • Architect: Assael Architecture
  • Contractor: McAleer & Rushe
  • Operator: Folk Co-living
  • Landscape: Farrer Huxley/Park Hood
  • Interior design: Assael Interiors/Atypical Practice
  • Planning approval: July 2019
  • Completion: October 2022
  • Occupation: November 2022
  • Site area: 0.54 ha
  • Gross internal area: 11,166 m2
  • Internal amenity area: 1,657 m2
  • External amenity area: 520 m2
  • Net internal area: 5,887 m2
  • Project cost: £35m