Jonathan Tuckey of Jonathan Tuckey Design and Jasmine Low, Senior Project Officer at the Greater London Authority, outline a radical strategy to transform the terraced house.

Elevation

Terraced houses are a quintessentially British typology. Collective and individual, the streets they create comprise a pleasing array of windows, front doors, chimneys pots and downpipes, articulating sophisticated palatial facades in their repetition. Since the 17^th Century, terraced housing has long established the foundations of British towns and cities, each type subtly scaled and adorned to reflect its inhabitants.

Together with public-facing front gardens and private back gardens to the rear, these buildings were conceived to provide the full hierarchy of spaces for dwelling; with interactions in the street differing from those over the garden wall. Meanwhile, the vast contrast in furniture and atmosphere between the front and back interior spaces, separated only by a 10cm partition, is to be desired and admired.

The UK has the oldest housing stock in Europe, with 38% constructed pre 1946 (EU average is 22%). Additionally, they are the smallest in Europe with an average floor area of 76m2. Since their conception, the typology has remained the same even though societal and environmental needs have changed exponentially. Many existing façades continue to be preserved, while the streets in front of them have been commandeered by cars, bins and the contagion of privacy. Rear elevations, having been extended with a riot of individual expression, are unrecognisable. Internal walls have come and gone; bathrooms, kitchens, water and waste have moved in. Uninsulated external walls, floors, roofs and single glazed windows remain unchanged.

Street view

Today, these buildings make up around 25%of the UK’s built stock, representing about 7 million homes. As government and institutional energy targets aim towards more sustainable and energy-efficient communities, it is essential that we make the necessary upgrades to terraced housing.

The challenges of retrofitting terraced housing to suit our future needs has quickly become a well-known and timeless tale. Navigating the planning system, seeking permission from both the council and neighbours, and confronting conservation restrictions amounts to being expensive, disruptive, and time-consuming. Even invisible interventions, such as implementing insulation, constrict our interior living spaces further – which have taken on additional significance in response to work and lifestyle changes following the COVID-19 pandemic. As the UK government promotes its 2050 net-zero goals, we have considered how we can help meet these targets by effectively transforming this most British built form. We envisage the power of retrofit at scale, transforming entire districts to work more efficiently for their inhabitants, whilst maintaining the legitimacy of terraces as sets, instead of single homes.

Garden view

Retrofitting the UK’s terraced housing stock nationwide requires a unified architectural response to a historic building tectonic. As Rasmussen Steen Eiler observed, ‘terraced housing is a true reflection of British character: while the fronts typically have a formal, unified facade, they are not uniform all the way around, with interiors and rears reflecting much more individual expression.’ Together with students from the London Metropolitan University, Jonathan Tuckey Design embarked on a study to explore the opportunities and challenges of extending and retrofitting properties en masse, examining an estate of terraced houses in the Queen’s Park area of London. This portfolio of work identified opportunities to move through the planning process, improve energy efficiency and provide an adaptable configuration of interiors. We additionally questioned how to maintain harmony between individual, private and the communal terracing through the reclamation of streets as pedestrianised realms and shared gardens.

Seeking an architectural solution to the singularity of the terrace, an additional upper floor is provided to the entire street. Constructed above the cornice, the new storey will be articulated like a decorative frieze, with bay windows and balconies overlooking the street. The new extensions are to be made entirely from cork; a lightweight warm insulated hat. This will enable simple pre-fabrication and assembly without the need for restructuring.

Office

Cork is not only an economic choice — it sequesters carbon and is highly insulating It is an extremely light-weight material, which is imperative when constructing roof extensions in order to avoid altering foundations. This allows construction to be done at scale with minimal disruption. Cork is unlike Cross-laminated timber (CLT) and other mass-produced timber products, which are heavier and require additional supports. It can act as the structure, insulation and water-proofing all at once, without requiring more intensive works or risking loss of interior space.

By complimenting materials typical to the terrace context such as bricks, terracotta and mouldings, cork enhances textural features. Retrofit is regularly viewed as incompatible with the authenticity of traditional architecture, leaving as an unseen, invisible and sympathetic act. This approach, however, simultaneously brings in a contemporary generation of architectural language to each individual home, and the terrace as a whole, adding our generation’s stamp to our urban situations without detracting from it.

Cork storey interior

This proposal was conceived for one set of buildings and we imagine that many types could be developed by the best architects of our time. Rather than exerting energy of thought solving individual housing extensions, imagine these minds being directed to the collective good.  We could develop and add to the vernacular of previous centuries with the creativity and thinking of present day.

Retrofitting terraced housing as a typology offers a powerful solution for crafting resilient cities in the wake of climate change. We are not only more likely to meet environmental and economic demands but enhance the quality of life for residents by encouraging community building and improved streetscapes through cohesive design. As we navigate the path towards sustainable cities, it is crucial to prioritise the transformation of existing housing stock.

Governments, local authorities, and communities must collaborate to develop comprehensive retrofit strategies to secure a greener and more prosperous future for all. By harnessing the power of mass retrofit we can unlock the full potential of terraced housing and provide comfortable, sustainable, and resilient homes for generations to come.