Alex Michaelis is co-founder of Michaelis Boyd Architects. The practice is known, in particular, for its outstanding period conversions and new-build houses around Notting Hill, including the residence of Prime Minister David Cameron.

Michaelis created this particular house for his own use. He acquired the plot with planning permission in place, and set about transforming the plans into a discreetly luxurious but low-energy space. Digging down 22 feet, he removed 1,000 cubic metres of London clay, hiding the house behind the existing brick wall. It is constructed primarily from concrete, and light is brought in to the lower floor using a combination of rooflights and sunken courtyards.

Of the property’s ecological features, Michaelis Boyd Architects say the following:

“The house’s subterranean design benefits from the ground’s insulating properties, lowering heating and cooling requirements. All additional energy requirements are achieved by using environmentally conscious systems. A passive, filtered, fresh air supply system with indirect heat exchange provides fresh warm air to all habitable rooms, minimising heat loss through ventilation and reducing airborne pollutants.

“A solar awning also houses photovoltaic panels, providing electricity to both the house and the electric car. With all the systems working together this home only requires minimal electricity from the grid during the winter months, and in the summer months it even returns surplus electricity generated.

“The borehole to the subterranean aquifer is 110 meters deep and the water extracted is filtered for domestic supply. The temperature differential is used via a heat pump to provide both the underfloor space heating and hot water for the house. The solar awning houses evacuated tube solar water heaters, which work alongside the heat pump to fulfil all domestic hot water requirements.”