Barton-on-the-Heath, Moreton-in-Marsh, Gloucestershire / Warwickshire border GL56

Underhill House is one of the most architecturally and environmentally important private homes ever constructed in the English countryside. Conceived, designed and built by architects Helen and Chris Seymour Smith between 2008 and 2010, it achieved international recognition as England’s first certified Passivhaus, setting a new benchmark for sustainable rural architecture. The house occupies an exceptional position beneath and beside a restored 300-year-old Cotswold stone barn within an Area of Outstanding Natural Beauty near Barton-on-the-Heath.

Excavated into the hillside and carefully concealed by the surrounding landform, Underhill House is almost entirely invisible from the landscape, achieving an extraordinarily low visual impact while benefiting from the thermal protection of the earth itself. Planning consent was granted under the highly selective ‘Exceptional Country House’ policy, reserved for homes considered to be truly outstanding and groundbreaking. Dug into the hillside and invisible from the surrounding countryside, the house has an exceptionally low visual impact while benefiting from the natural insulation of the land. Underhill achieved national recognition as England’s first certified Passivhaus and was featured on Grand Designs in 2010. Arranged in an L shape and oriented due south, the principal elevations are almost entirely glazed with high-performance triple glazing, maximising solar gain.

Constructed from highly insulated concrete and built to rigorous Passivhaus standards, the house is virtually airtight, extremely energy efficient and naturally warm, with minimal heating requirements and exceptional year-round comfort. accommodation is arranged on one level, centred around a large open-plan living space in a loft-style arrangement, with the kitchen and dining area forming the heart of the home. The contemporary kitchen features extensive Corian work surfaces and a substantial island, opening to a sitting and library area with a wood-burning stove. Additional rooms include a cinema room, gym/store room, two studies and a utility room with an adjoining wine store, leading to the triple garage.

All four bedrooms open directly onto the terrace. The principal suite includes a dressing room with a generous bathroom adjacent and a fifth bedroom currently used as a study. Three further double bedrooms, each with an ensuite, are on hand.

A sheltered, paved terrace with a slate water feature provides excellent space for outdoor entertaining, with lawns rising gently beyond into open countryside. Underhill House is accessed along a private track leading to adjacent farmland. The property enjoys right of way over the drive and contributes 25% to its maintenance.

Above the main accommodation is a beautifully converted self-contained annexe, featuring a sitting area with a kitchenette, bathroom and a mezzanine bedroom accessed via a spiral staircase. It opens onto a decked upper terrace with spectacular far-reaching views alongside a walled garden with raised beds. There is an orchard and ample off-road parking at the front of the property.

Water is supplied via a private borehole, with private drainage served by a Bio Pure treatment system. Temperature and air quality are regulated by an MVHR system (Mechanical Ventilation with Heat Recovery), which extracts warm air from kitchens and bathrooms, filters it and reuses the heat to warm incoming fresh air.

Hot water is primarily provided by a solar thermal system installed on the south-west-facing roof of the barn, with additional backup from the wood-burning stove or the electric immersion heater. Photovoltaic solar panels generate a significant proportion of the property’s electricity, benefiting from a high rate Feed in Tariff, while remaining connected to the mains grid.

Underhill House is situated on the edge of the highly regarded village of Barton-on-the-Heath, set within some of the finest rolling countryside on the Warwickshire/Gloucestershire border. The village is known for its unspoilt rural character, attractive stone houses and strong sense of community, yet remains exceptionally well connected.

The property lies between the market towns of Moreton in Marsh and Chipping Norton, both of which provide for everyday needs, including a wide selection of independent shops, restaurants, cafés and supermarkets. The renowned Daylesford Organic Farm Shop is just over 5.5 miles away, while Soho Farmhouse and Estelle Manor are approximately 12 and 18 miles distant, respectively. The cultural centres of Cheltenham, Stratford-upon-Avon and Oxford are all within 25 miles, offering a broader range of shopping, sporting and cultural amenities. Communications are excellent, with a regular mainline rail service from Moreton-in-Marsh to London Paddington, as well as convenient road access via the A44 to the M40 and Oxford Airport.

The area is particularly well regarded for schooling, with Kitebrook Preparatory School nearby and a strong choice of respected state and independent schools including Bloxham School, Cheltenham Ladies’ College, Tudor Hall, St Edward’s and Sibford School, alongside a local primary school at Long Compton.