An Eco Self Build in Devon

For Lucy Rutherford and her husband, Martin Hutchins, building their own house has been a life-changing experience in more ways than one. Situated in an Area of Outstanding Natural Beauty, Pebblebed House was designed to be a low-energy building with minimal impact on the environment, and the couple selected natural materials and designed the garden to encourage wildlife, as well as growing their own organic vegetables. The change from their previous city life in Bristol couldn’t be more pronounced.

“We planned to move to this part of Devon to be close to the Exe River — which we know very well,” says Lucy, a former film sound editor, “and we lived in rented accommodation while we searched for a suitable house to renovate. When we found this quarter-of-an-acre site, there was already a small bungalow here, but we decided to try and replace it. We talked to the planners at length before we put in our planning application, and they were fairly supportive when they realised that we wanted to build a sustainable house.”

For some time, Martin and Lucy had hoped to live a more environmentally friendly lifestyle, and building Pebblebed House offered the perfect opportunity to put their ideas into practice. The design was, therefore, very much eco-led, but was also influenced by the couple’s relatively modest £200,000 budget.

“Building an eco house is definitely getting easier to do, but most builders still tend to suck their teeth when you start talking about rainwater harvesting and energy conservation,” Lucy explains. “We undertook quite a lot of research and visited the Centre for Alternative Technology in Wales to find out what would be possible and what we could afford.”

Lucy and Martin chose Paul Humphries Architects, a local practice known for its energy-efficient and sustainable designs, who worked with them to determine a brief for their new home. The footprint of the house is virtually the same size as that of the previous bungalow, but an insulated curved roof formed over glulam beams has enabled two bedrooms and a bathroom to be situated on the first floor whilst meeting planning requirements to remain below the chimney height of the original pitched-roof bungalow.

Reorientating the building ensures that it benefits from passive solar gain, with the main living room and kitchen positioned facing south-west and the smaller utility, wetroom and study located to the east side of the house. The curved living room is a single storey element with a wall of full-height glazing, rooflights and a large overhanging flat roof of sedum matting — which encourages birds and butterflies, absorbs around 75% of water run-off and helps to keep the room at an even temperature. In addition, the couple have also covered a section of the larger curved roof with solar panels to preheat their hot-water supply.

In order to save money during the build, they put their belongings into storage and moved into a caravan on site, which proved to be fairly grim. They then set about demolishing the old bungalow themselves, and managed to recycle many of the materials including timber, hardcore and tiles, before employing a local farmer-turned-builder who had been recommended by a friend for the complicated groundworks.

Despite the fact that he had never previously built a new house, Martin and Lucy were so impressed by the accuracy of his work that they asked if he would go on to complete the main structure of thin-joint solar blockwork. Compact thermo-reflective insulation was later fitted between the single skin of 215mm blocks and the internal plasterboard. With so many strange angles to accommodate, the project was not particularly straightforward, but the builder proved to be the perfect choice and was happy to take on any challenge without exceeding the fixed price he had quoted.

Many local village houses in this area have characteristic ‘poppled’ walls, where old river pebbles have been set into lime mortar to create an unusual and hardwearing finish, and Martin and Lucy were keen to follow this tradition. They used pebbles dug from their site and incorporated poppled battered walls and buttresses on the ground floor of the house, offset by areas of lime-washed render and horizontal larch cladding. Instead of gutters, the louvred metal rain-handlers send rainwater out in a fine spray.

“Martin had taken time out from work to project manage the build and planned to complete some of the physical work himself, including the plumbing and dry-lining,” says Lucy. “However, in February 2004, he suffered a major stroke which was a total shock and has left him wheelchair-bound. Not surprisingly, everything came to a sudden and complete halt on site. The scaffolding was arriving that day as the roof had been due to go on, and we were extremely fortunate that my brother and some very good friends stepped in after a few weeks and started things going again. I was at the hospital each day and wasn’t able to offer much help at this point, but luckily Martin had kept excellent diaries and notes on the build, which were invaluable, and our builder was extremely helpful and sympathetic.”

Fortuitously, Martin had been keen to make the ground floor of the house fully wheelchair accessible, following a brief time spent in a wheelchair with a broken leg, and incorporated extra-wide doorways and flat thresholds into the original design. By the time he was well enough to leave hospital, 17 months after his stroke, the majority of the ground floor rooms were completed and the former study had been converted into a third bedroom. Martin was absolutely delighted to see the progress which had been made on the house and, although he has yet to see the two first floor bedrooms with their curved ceilings, plans are afoot to eventually fit a stair-lift.

Despite this unexpected turn of events, the couple were determined that the eco credentials of their home would not be compromised. Local craftsmen undertook the plastering, joinery and electrics, and Lucy and their friends completed the project using environmentally friendly paint, limewash and hard-wax oils.

A geothermal heat pump serves the underfloor heating and hot water, harnessing natural warmth from below the ground and supplementing the solar panels in winter. Even during the coldest weather, the temperature within the building remains consistent thanks to the combination of double and triple glazed windows, a heat-recovery and ventilation system, insulation, passive solar gain and the sedum roof — a far cry from the couple’s previous draughty Victorian house.

Outside, this effect is further aided by the new earth banks created to the north of the house and built up in layers using soil excavated from the foundations. The site is relatively flat, open and exposed, and forming these sedum-covered banks to either side of the back door provides additional insulation and also helps to keep the larder cool — ensuring a degree of shelter to the most exposed wall of the building whilst helping it to recede into the natural landscape.

Two new ponds have also been dug in the garden. One is positioned outside the curved glass wall of the living room and collects rainwater from the sedum roof, reflecting light back into the building and acting as a cooling element in summer. The other was designed purely to encourage wildlife to the site and has already attracted a variety of newts, frogs and dragonflies.

“We put up bat boxes and bird nesting boxes,” says Lucy, “and there are three composting areas which help us to grow organic vegetables such as onions, leeks, spinach and courgettes. We also have our own water supply thanks to an existing well, so we do feel as though we are relatively self-sufficient. In the future, it would be nice to have a small wind turbine to produce electricity, but for now we are more than happy with the house and our new way of living. In spite of what has happened, we still feel very fortunate indeed to be here and to be able to enjoy such a beautiful setting.”