Bathwick Hill House, Bath

Dates: 2005 - 2007

As featured on Channel 4's Grand Designs

Lead Architect Craig Underdown was commissioned in late 2005 by clients Tiffany and Jon to design a family home for the plot which nestles between North Road and Bathwick Hill.

Tiffany and Jon had secured the site with an existing planning consent, but their brief was to replace the unremarkable building with something more befitting the unique site.

Driven by a love of Modernism, and with particular reference to nearby Kilowatt House – Bath’s only Art Deco residence – Tiffany and Jon asked Craig to design a family home in tune with this distinctive 20th Century architectural style, whilst incorporating elements of sustainability to ensure its place in the twenty-first century.

The resulting house is a stunning contemporary-style timber framed German (Baufritz) built home, partially clad in Bath stone in order to ensure that the building is sympathetic to the surrounding Bath architecture.

The House

A steep entrance drive leads up to the house via a landscaped garden, to an area of decking to the front of the building laid by local company Grand Deck Design.

Steps lead to a large oak double front door, and into a double-storey, triple glazed lobby, with superb views back across the entrance to the valley below.

Inside the house a beautiful elliptical staircase forms the stunning centrepiece of this unique five-bedroom home.

The house has been built on top of a complex two-storey basement structure, housing a double garage, plant room, large store room, and wine store. The ground and first floors are also split-level. The entrance hall is at an intermediate level and houses the impressive elliptical staircase. The curved wall of the staircase is covered in heather self coloured polished plaster, giving the interior a highly personal feel.

The raised level houses the lounge with wood burning stove; the brightly-coloured kitchen is on the lower platform.

Also on this level is a balcony to the front, music room and study. A variety of luxurious timbers feature throughout: untreated oak and walnut doors, and a natural oiled oak parquet flooring in the lounge, while the window frames are a mixture of spruce and oak.

The home is completed upstairs with a master bedroom with dressing room and ensuite bathroom, four further double bedrooms, two bathrooms and a linen room with a laundry chute to the utility room below.

The whole house is beautifully lit. Triple glazed windows follow the curve of the stair and a large skylight above the staircase as well as the glazed entrance means that the house maximizes natural light despite being enclosed on three sides. The house has a flat, gravelled roof and a coloured render on the external walls that contrasts with the bath stone cladding detail on the front facade. To the rear of the building there is another small raised garden area.

The Challenges

The project’s challenges began almost as soon as planning permission was granted and work on-site began.

The planning consent required the building to remain within certain height constraints, so the plot had to be lowered to form a level base for the basement works

Contiguous piling and concrete retaining structures had to be installed to stabilize the soft clay soil, and with the site on a very steep slope, and surrounded by buildings on three sides, local engineers Mann Williams worked hard to solve the many practical tests posed by the project.

However after a year of delay, frustration and technical problems, the house arrived prefabricated from Germany, and was erected in just three days.

Modern and Sustainable Building Techniques

The house, which is built entirely from bio-constructive, efficient and natural materials, employs various state-of-the-art techniques to reduce its environmental impact and enhance the quality of day-to–day living.

Solar panels

12m² solar panels on the flat roof heat the water stored in a tank in the basement.

Water Harvesting

A rainwater harvesting system in the basement supplies water to the toilets, washing machine and garden taps.

Heat exchange air extract/supply

Six decentralised reverse fans (LTMs) extract warm air from the room, pass it through the heat exchanger, and store the heat extracted from the air in the unit. The fans change direction; fresh air brought in from outside passes through the unit, and is warmed by the stored heat before entering the room. In warm weather, the effect is reversed, thus cooling the warmer outside air before it enters the house. All of this significantly lowers the level of energy required to heat the house.

Electromagnetic Radiation Shield

The house also incorporates “XUND-E”, a unique protective shielding concept, which dramatically reduces the amount of electromagnetic radiation penetrating the home.

Carbon Positive

The house is carbon positive, locking away more CO2 than is emitted during its construction and manufacture, including transportation emissions and those from the running of the house for the first 5-10 years.

Thermal Efficiency

The external walls are 40cm thick and packed with highly efficient wood shaving insulation. These thick walls are breathable which ensures that condensation is removed from the atmosphere faster than it is generated, making the living environment inside the house comfortable and fresh.

The wood shavings are left over from the manufacturing process so waste is minimised; and are protected from fire, fungus and pests using a natural treatment made from soda and whey.

Energy and heating oil consumption is about six times less than a typical UK house