CURVE HOUSE

Area: 325m2

Procurement: Self Build – Project Manager – Nathan Davis

As Built SAP: 88B without PV & Batteries.  Environmental Impact: 92A With Solar Panels/Batteries: A

Embodied & Operational Carbon: 493 KgCO2/m2 (Best Practice 2020 is <500 KgCO2/m2)

Construction Stage Air Pressure Test: 0.62

LABC: Cornwall Council (Plan Check, Inspections)

Set on a challenging, irregularly shaped plot and working within a tight budget, this project presented a unique opportunity to create a multigenerational home that not only adapts to the evolving needs of its occupants but also offers income potential during retirement.

Positioned at a key threshold into Cornwall, the site boasts sweeping panoramic views and an exceptional solar orientation, a rare combination that allowed for bold architectural freedom. The resulting design is both sensitive and striking: low-maintenance, future-proof, and deeply connected to its context, all while maximising the site’s natural assets and long-term sustainability.

From the moment we acquired the site, our intention was to create a truly personal, long-term family home, one that would support us through every stage of life. We sat together as a family and developed a detailed wish list that would go on to shape the design in a meaningful and highly intentional way.

This was our first and only opportunity to build something from scratch, a home that reflected how we live now and how we hope to live in the future.

Our key requirements were as follows:

Low Running Costs & Sustainable Living
The home needed to be energy efficient and cost-effective to run. We wanted to integrate passive solar design, harness renewable energy, reuse rainwater, and reduce our environmental footprint through super-insulation and careful material choices.

Seamless Indoor–Outdoor Living
A core aim was to connect interior spaces with the garden – allowing for easy flow between inside and out. We wanted our children to grow up with a strong connection to nature, and for the home to feel open, social, and flexible in how it could be used.

Adaptability for Multigenerational Living
The design needed to include breakout spaces for teenagers and high-energy activity, while also offering the flexibility for our parents to live with us in later years. The home had to be futureproofed to adapt over time, supporting different life phases without the need for major alterations.

Health-Responsive Design
With a family member living with Type 1 diabetes and an associated degenerative eye condition, the quality of natural light was a critical consideration. The home had to deliver abundant, consistent daylight, while also allowing for control of glare and heat. Every room needed to maintain a healthy, comfortable environment throughout the year.

Income Potential in Retirement
A portion of the home was to be designed with the potential for independent letting in future years, providing supplementary income during retirement. This element needed to be integrated discreetly, without compromising the home’s overall function or privacy.

Low Maintenance Living
Above all, we wanted to live in a beautiful home, not for it. The design had to minimise maintenance, allowing us to enjoy the house and the setting without being burdened by upkeep.

Celebrate the Views
The site offers remarkable panoramic views – a true gateway into Cornwall. These views had to be embraced and celebrated as part of everyday life, framing our connection to the landscape and shaping the experience of the home.

The concept for this home was born from a highly constrained site with an irregular footprint, no height restrictions, and a deeply personal brief focused on sustainability, multigenerational living, and a hands-on self-build ethos.

The site’s topography and orientation lent themselves naturally to a vertical solution. Embracing a four-storey form allowed us to optimise floor area while maintaining a compact footprint, an efficient form factor that helped minimise embodied carbon. The house is partially sunken into the landscape, reducing its visual impact and creating a grounded, haven-like atmosphere that responds sympathetically to its surroundings.

Central to the concept was the desire for free-flowing living, a seamless connection between indoor and outdoor spaces, with natural light, garden views and family interaction at the core. A gently curving main façade hugs the garden, offering a sense of protection and peace. This gesture informed the building’s organisation into two wings: one housing utility spaces and services and the other designed for play and future teenage independence. Between them sits the heart of the home — an open-plan kitchen, dining, and living space that acts as the social core of the house.

The upper floors are arranged to maintain visual and physical connection between levels, with a double-height central void and open gallery walkway. A second-floor social space — with kitchen potential and additional bedrooms — extends the home’s adaptability, allowing for future income or independent living if required. Two roof terraces at this level celebrate the panoramic views across Helman Tor and Brown Willy, reinforcing the connection to place.

Passive design principles underpin every decision. Natural purge ventilation is achieved through high and low-level windows with automated controls. A MVHR system ensures balanced heat recovery and humidity control throughout, supported by a service-led layout that simplifies ducting routes and enhances long-term maintainability.

Material choices reflect both sustainability and the self-build nature of the project. Birch plywood provides warmth, texture, and visual consistency across joinery, thresholds, and stair elements. Its durability and ease of use made it ideal for self-construction. The bespoke central staircase, constructed from steel, glass, and timber, serves as both a functional and symbolic heart of the home, a visible expression of the family’s effort and craft.

This project is not just a home, it is an architectural response to site, need and future. Designed to be low-maintenance, adaptable, and deeply connected to landscape and lifestyle, it offers a template for sustainable, joyful multigenerational living.

A key driver of this project was the ability to self-build – using available skills, time, and space to control cost and construction quality. To support this, we elected to use a timber frame construction system, which allowed us to capitalise on self-build potential and manage the process incrementally, whilst minimising our carbon impact.

The frame was constructed piece by piece in a nearby shed (we built before starting the main house)after work hours, then erected over weekends. This methodical, modular approach enabled us to fund the build in stages and manage it around family and work commitments – a true labour of love.

At ground floor level, where exposure to moisture was a greater risk, we used tanalised timbers for added durability and longevity.

Structurally, we developed an unconventional twin timber frame system, with the internal and external frames separated by an insulated cavity. These frames were lightly connected using minimal gusset fixings to preserve structural stability while reducing thermal bridging across the building envelope to a minimum.

Steelwork was kept to an absolute minimum. Instead, we relied on glulam timbers to provide the necessary spans and integrity – a more cost-effective, sustainable, and self-build-friendly solution. All sheathing boards were glued and screwed to the timber frame, with every internal wall treated as a racking walls to maximise the building’s overall stiffness and performance.

The roof structure used I-section beams with both above and below counter-battens, allowing additional insulation while minimising cold bridging and maintaining continuous thermal performance across the fabric. This thoughtful layering improved buildability while maximising energy efficiency. This also uses less timber compared to solid lumber.

This hands-on construction approach not only reduced costs and embodied carbon, but also embedded a deep personal connection into every element of the home – a structure quite literally raised by the hands that live in it.

Externally, the home is clad in a carefully considered combination of natural slate, zinc and painted fibre cement sheeting, all selected for their longevity, ease of maintenance, and compatibility with the rural setting.

Each of these materials has a life expectancy of 30 years or more, and all are easily cleaned, requiring minimal upkeep, a key part of the low-maintenance strategy for the property.

The use of natural slate and fibre cement sheeting draws on materials traditionally seen in rural and agricultural buildings, providing a visual connection to the context and heritage of the landscape. These finishes create a contemporary expression while respecting local material language.

The painted fibre cement sheeting in particular has proven to be an exceptionally cost-effective solution. When compared to similar architectural cladding products – such as those manufactured by Eternit – the fibre cement used on this project was approximately 90% more affordable per square metre, allowing us to achieve a refined aesthetic on a limited budget without compromising on performance or durability also manufactured in the UK and quick to install.

Careful attention was paid throughout the design and construction process to protect and enhance the site’s ecological value. While no bats were found during the Phase 1 Ecology Survey, visual appraisal, or emergence monitoring, potential roosting opportunities were deliberately integrated into the new build – including zinc parapet flashings where bats may tuck themselves away in future.

Further biodiversity enhancements include integral bird boxes built into the structure to encourage nesting, and strategically placed holes for solitary bees, helping support a wider range of local wildlife. New Cornish hedgerows also provides a super highway for wildlife.

A key feature contributing to biodiversity net gain is the wildflower green roof, installed on the workshop and gym, which were ingeniously formed from an upcycled site container used during construction. This living roof, combined with a sensitive, pollinator-friendly planting scheme, provides rich habitat for bees, butterflies, and other invertebrates, actively supporting local ecosystems and promoting species diversity.

Functionally, the green roof also assists in managing rainwater runoff – acting like a sponge to absorb rainfall and slow flow during peak events, contributing to sustainable drainage and climate resilience on site.

Throughout the seasons, the house has consistently delivered a comfortable, stable internal temperature of 20°C+ without heating, capitalising on solar gains from the low winter sun, while effective solar shading prevents overheating during the summer months. The result is a living environment that is both cost-effective and deeply comfortable – surpassing our expectations on every level.

The roof-mounted photovoltaic system generates up to 10kW of solar energy at peak, paired with a 20kW battery storage system. For a large portion of the year, this system powers the entire home, drastically reducing our reliance on the grid and keeping operational costs remarkably low.

Thanks to exceptional airtightness and super-insulated walls and roof (up to 600mm thick), the need for mechanical heating is almost non-existent. In fact, the central heating system is typically only turned on for two weeks over Christmas when guests are staying – and otherwise run once a month for a short maintenance cycle to keep the pumps active.

This real-world performance reflects the success of the design’s passive strategies and fabric-first approach, proving that a self-build family home can deliver high-performance, low-energy living without compromise.

The greatest challenge in this project was undoubtedly creating such a complex and ambitious building on an extremely limited budget. It demanded not just careful planning, but the willingness to embrace a vast array of new skills – all while applying over 20 years of architectural experience in a hands-on, entirely new way.

This was not just a design exercise. It was a real, raw test of how to build a home on a hand-to-mouth basis, where materials were purchased as funds allowed, and progress followed suit over a 4 year period.

To reduce labour costs, we invested in a second-hand telehandler, which enabled us to carry out much of the heavy lifting ourselves. Learning to operate it – with no prior experience – was an adventure (and a challenge) in itself, but it opened up freedoms that would otherwise have been unaffordable.

But the biggest challenge wasn’t the technicalities. It was the time taken away from my beautiful family, the long nights, and the constant effort to stay motivated through fatigue and setbacks. Balancing the emotional, physical, and financial demands of a self-build at this scale stretched us all.

And yet, it was worth every moment. The journey has been humbling, empowering, and full of delight – and the result is not just a building, but a legacy we crafted with our own hands.