British architectural firm Hewitt Studios LLP recently completed work on the 400 sq m (4,305 sq ft) UK-based Limpley Stoke Eco-House. Designed with a focus on sustainability and energy efficiency, the futuristic home features more green technology than you can shake a (sustainably-sourced) stick at, including rainwater collection, passive ventilation, solar power, and an EV charging point.

The house derives its name from the tiny village in southwest England in which it is located, and was built using a combination of prefabricated and renewable construction materials, some of which was sourced locally. The walls of the second floor incorporate prefab timber panels, and sustainably-grown timber from certified forests was also used in the build.

Insulation comes courtesy of environmentally-friendly straw bales, and the ground floor features concrete made using pulverized fuel ash – a waste product of coal-fired power stations that offers excellent insulation values.

As is the case in some similar energy-efficient properties such as the Tighthouse, Limpley Stoke Eco-House's near air-tight envelope allows it to maintain a more stable temperature than a typical home. A mechanical ventilation and heat recovery (MVHR) system expels unwanted warm moist air, and draws in new fresh air from outside. The outside air then passes through a heat exchanger system and warms the interior of the house efficiently. This mechanical system is also complemented by passive natural ventilation.

When the weather turns too cold for the MVHR system alone, a log burner is available, and the home's extensive grounds include a woodland area slated to provide a sustainable source of firewood. Elsewhere in the grounds are a bat roost, and a small garden studio complete with composting toilet and log burner.

Solar power is harnessed for both electricity and water heating needs. The front edge of the Limpley Stoke Eco-House sports a sun shade which has 2 kW solar photovoltaic panels affixed. The roof supports a solar water system that creates hot water for domestic use, with a standard electric immersion system kicking in when solar power proves inadequate.

Other sustainable features present in the Limpley Stoke Eco-House include a green roof that's home to hardy low-maintenance plants native to the north of England. The green roof both reduces the visual impact of the building and provides an additional layer of insulation.

Also on the roof is a rainwater harvesting system, which processes water with an onboard filtration system before it is then used as irrigation for the vegetable and herb garden, and for washing the owner's BMW i3 electric car. The BMW i3 is charged by an EV charging point that's located toward the front of the property, itself supplied with power from the building’s PV panels when weather permits.

Hewitt Studios states that the annual predicted CO2 emissions of the home are 774 kg (1,706 lb) of CO2 per year, and that its predicted energy demands are 4,880 kWh per year. The construction of the house took 18 months to complete and cost a total of £1.5 million (roughly US$2.5 million).

Source: Hewitt Studios LLP