Emil Eve Architects has completed the transformation of a former nursery in Hertfordshire into Harpenden House, a family residence defined by three distinctive, staggered rear extensions and an intelligent application of ultra-slim sliding doors to achieve broken-plan living. The RIBA award-winning project successfully merges the building’s Edwardian character with a minimalist Scandi aesthetic.

The project brief focused on stripping back the dated interior to create a contemporary space, prioritising an uninterrupted connection to the garden. Rather than opting for a single, typical rear extension, Emil Eve Architects developed a visually dynamic full-width addition composed of three angled volumes. The volumes are topped with a distinctive sawtooth roof that flows across the extension, a design choice deliberately used to break up the overall scale, allowing it to sit more sympathetically against the original house.

This architectural intervention informed the ground floor’s new versatile layout. The kitchen, dining, and living areas are interconnected but designed to be segmented as needed, aligning with the “broken-plan” concept. Crucially, each of the new rooms opens independently to the exterior. This concept culminates in a stunning post-free open corner where two of the new volumes meet, featuring large sliding doors that completely dissolve the wall and create a seamless transition to a sheltered patio area.

The seamless indoor-outdoor experience is facilitated by the firm’s recommendation of IDSystems’ theEDGE2.0 doors. These award-winning systems boast 20mm sightlines, offering near-uninterrupted external views and robust high-performance insulation for comfortable year-round use. According to Edward Stobart of IDSystems, the clients aimed for more than just an open connection—they desired a constant, tangible link to the garden, a goal that the slim-frame sliding doors were uniquely positioned to deliver.

The glazing package uses the doors in three different ways, enhancing the spatial definitions. A three-panel set that stacks neatly is used in the kitchen for maximum opening, while the dining space features a sliding window ingeniously combined with a built-in window seat. The aforementioned open corner sliding doors in the living room function as the main boundary-blurring element, demonstrating the flexibility of the chosen IDSystems product. The RIBA East 2025 judges specifically noted how the space is modulated by daylight filtering through four different-sized rooflights within the sawtooth profile, highlighting the client’s enjoyment of the changing patterns of light.

Breaking from the often stark white box of modern extensions, Harpenden House employs a warmer, textured material palette. The addition features handmade waterstruck yellow bricks paired with glazing frames finished in Light Ivory (RAL 1015), a choice made to soften the contemporary lines and subtly reference the original home’s Edwardian tones. Inside, the focus shifts to warm modernity with muted teal cabinetry anchoring the kitchen, balanced by extensive use of natural timber elements to provide softness and tactility. These sophisticated finishes, including classic Scandinavian furniture pieces like an Ercol Easy Chair, result in a highly livable and stylish home that is deeply rooted in its context while embracing a contemporary functional brief.