Located on Plot 5 of a five-home development in Hertfordshire, Doone Brae Farm is a one-of-a-kind, architecturally ambitious home is the largest and most technically advanced in the group. Designed to reflect the client’s commitment to sustainability and off-grid living, it blends bold architectural form with exceptional environmental performance — achieved in close collaboration with Lowfield Timber Frames.
Design-Led Performance
From the outset, the client envisioned an ultra-low energy home that pushed beyond regulatory requirements. The building’s sinuous S-shape and twisting sedum roof respond to site constraints like noise, solar orientation, and planning input. As a result, the curves soften the landscape, shield private gardens, and enhance the development’s character.
South-west-facing glazing not only captures valley views but also maximises passive solar gains. Meanwhile, deep windows revealed by 400mm Larsen panels provide effective passive shading, helping to prevent overheating. Vertical timber cladding flows with the curved form, and green roofs visually tie the home into the surrounding hedgerows and rolling topography.
Fabric-First Approach with Lowfield Larsen System
Although the original planning scheme wasn’t designed to meet Passive House standards, the client’s drive for ultra-low energy performance led to a complete redesign around Lowfield’s Larsen truss system. This fabric-first approach delivered U-values of 0.1 W/m²K to walls, roof, and floor, with an airtightness result of just 0.5 ACH — the best ever recorded by the airtightness assessor.
Early collaboration between the architect, client, and Lowfield was critical. Prefabricated wall panels, insulated roof cassettes, and coordinated M&E service routes enabled rapid, precise construction on site. The team erected the structure and made it watertight in a matter of weeks, reducing weather risk and enabling the internal fit-out to begin early.
Sustainable Materials and Off-Grid Systems
The client, a seasoned eco-builder and founder of Living Space Homes, shared Lowfield’s values of sustainability, local sourcing, and energy independence. Every material choice was made with embodied carbon in mind. Key features include:
- PEFC/FSC-certified timber and low-carbon glulam for key structural spans
- Carbon-positive insulation within the Larsen panels
- Burnt larch cladding offering 50+ years of low-maintenance performance
- Locally sourced labour and trades to minimise transport emissions
The home operates almost entirely off-grid, powered and serviced by:
- A 75m-deep ground source heat pump
- A 20kW solar PV array
- An on-site borehole for water supply
Comfort, Craftsmanship, and Detail
Beyond energy performance, the Doone Brae Farm is a model for thermal comfort and indoor wellbeing. Natural materials, deep reveals, and careful ventilation strategies support a healthy internal environment, while low operational costs ensure long-term sustainability. The deep window reveals — initially a performance-driven detail — also adds strong architectural depth and visual interest.
Choosing glulam beams over steel for the large spans reinforced the timber-first narrative and enhanced the home’s sustainable credentials. Every element was carefully resolved prior to construction, ensuring a defect-free delivery and outstanding build quality.
Client Testimonial
“This is the best-performing house I’ve ever lived in. The Lowfield system delivered what others only promised. The quality of finish, comfort, and support throughout the process has been second to none.”
Designed with JDW Architects, the home blends sculptural form with practical environmental responses. It shows how thoughtful architecture pairs effectively with precision off-site construction.
The Wienerberger UK Blend 32 Brick Slips from The Brick Tile Company highlight how smart material choices can elevate timber frame construction. Their textured, earthy finish adds depth and contrasts beautifully with the natural timber.
Structural engineering was provided by Paramount Structures, whose expertise helped bring the complex architectural vision to life with precision and efficiency.
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