Eco-house: 8 Beautiful Dwellings that Are Cheap and Efficient

An eco house is a home designed to use far less energy and water than a typical house of its size and climate, mostly through orientation, insulation, airtightness, shading and natural ventilation, with renewable energy added on top. It does not have to be expensive: the cheapest savings come from design decisions, not gadgets. This guide is for homeowners, students and design-literate readers. It explains how an eco-house works, where each strategy suits (and where it does not), and checks eight built examples against their published sources.

Heating and cooling are among the largest energy uses in most homes, so cutting them is the main lever. The low-cost moves are well established: face the main glazing towards the winter sun (south in the northern hemisphere, north in the southern), size roof overhangs to block high summer sun, place windows for cross-ventilation and daylight, and insulate and seal the envelope. Prefabricated timber construction can also reduce site waste and build time, as several of the houses below show. For more examples, see Sustainable Houses Make Beautiful Places to Exist.

How an eco house works

The US Department of Energy’s guide to passive solar home design describes five elements that work together: an aperture (glazing facing the winter sun), an absorber (a dark surface in the sun’s path), thermal mass to store the heat, a way to distribute it, and controls such as overhangs, vents and blinds to stop overheating. In warm climates the emphasis flips: shading, insulation of the roof and convective ventilation through high-level openings matter more than collecting sun, as the Australian Government’s Your Home passive cooling guide explains.

The most rigorous version of this approach is the Passive House (Passivhaus) standard. According to the UK Passivhaus Trust, a certified building must keep space heating demand below 15 kWh per square metre of treated floor area per year and reach an airtightness of no more than 0.6 air changes per hour at 50 Pa. The first such house was a terrace of four dwellings in Darmstadt-Kranichstein, Germany, completed in 1991.

Where each eco house strategy suits: climate and building type

No single eco house recipe works everywhere. Large south-facing glass that warms a house in a cool, sunny climate can overheat it in a hot one, and heavy thermal mass that evens out desert temperature swings does little where nights stay warm and humid. The table below summarises the general guidance; local building codes and climate data govern any real design.

Eco-house examples: a selection across the globe

The eight houses below range from a self-build flood house in Vietnam to a designer prefab range. Where the original version of this article gave prices or savings that could not be traced to a source, they have been removed or corrected.

1) Bamboo homes at Green Village (IBUKU, led by Elora Hardy, Bali, Indonesia)

Elora Hardy founded the design firm IBUKU in Bali in 2010, and its houses at Green Village, near Ubud, are built almost entirely of bamboo. Because no two poles are identical, each house takes its own curved form. In her 2015 TED talk, Magical houses, made of bamboo, Hardy explained that the team had to devise its own building rules, since conventional codes and drawings did not fit the material. Open walls and tall roofs give good cross-ventilation in Bali’s hot, humid climate. Note that these are luxury villas, not low-cost housing: bamboo is cheap, but the craft is not.

2) Pop-Up House (Multipod Studio, Provence, France)

The Pop-Up House prototype was assembled, according to its designers, in four days with only an electric screwdriver, as Interesting Engineering reported. Its walls are built like stacked LEGO blocks: insulating blocks of expanded polystyrene fixed between timber elements, light enough to lift by hand. The designers aimed for passive-house levels of insulation and airtightness so that little or no heating is needed in the mild southern French climate, as Futura Sciences described.

3) Blooming Bamboo Home (H&P Architects, Vietnam)

The Vietnamese architectural firm H&P Architects designed this 2013 prototype as a low-cost home for flood-prone rural areas. It stands on stilts, is designed to cope with floods up to 1.5 metres (5 feet) deep, and the firm was testing a version for 3 metres (10 feet). The 44 square metre (473 square foot) frame is made of bamboo modules, with fibreboard and coconut leaves as infill. New Atlas reported that owners could build it in about 25 days and that it was expected to cost around US$2,500 (2013 estimate; what that price includes was not published).

4) Illawarra Flame (Team UOW, University of Wollongong, Australia)

A team from the University of Wollongong and TAFE Illawarra retrofitted a 1960s-style Australian fibro house into a net-zero energy home and won Solar Decathlon China 2013 in Datong with 957.6 points out of 1,000, as RenewEconomy reported. The organisers described it as the first retrofit of an existing house in the competition’s history. The redesign opened the bedrooms into living space and added prefabricated pods for the bathroom and laundry. Its lesson is that an eco house can be an upgraded existing home rather than a new build.

5) P.A.T.H. (Philippe Starck with Riko, France and Slovenia)

The French designer Philippe Starck worked with the Slovenian timber prefab maker Riko on P.A.T.H. (Prefabricated Accessible Technological Homes), a configurable range announced in 2012. Buyers can choose wood, glass or mixed facades. Designboom lists photovoltaic panels, wind turbines, rainwater collection and heat pumps as possible additions, so these are options rather than standard features. The first built example, a two-storey house in Montfort-l’Amaury, France, was shown in 2014.

6) Hupomone Ranch (Turnbull Griffin Haesloop Architects, Petaluma, California, USA)

This barn-like family house stands on a roughly 160-acre homestead in Chileno Valley, west of Petaluma. Its wood walls of western red cedar and its corrugated metal roof are painted white. According to the Petaluma Argus-Courier, the house is LEED Platinum and uses thermal mass, geothermal heating and cooling, and photovoltaic panels; Architect magazine reports a 10-kilowatt solar array that offsets the family’s energy use. It shows how a simple, compact form keeps the envelope efficient.

7) Eco-Sustainable House (Djuric Tardio Architectes, Antony, near Paris, France)

This two-storey house in Antony, just south of Paris, has a pitched roof that looks unfinished. Instead of closing it, the architects left it as an open pergola and turned it into a planted roof terrace with kiwis, squashes and grapes, watered by harvested rainwater, as Dezeen reported. The structure is made of prefabricated panels of Finnish timber from sustainably managed small private forests, filled with wood-fibre insulation, and it was assembled on site in two weeks.

Large double-glazed windows on the south side let in winter sun, while the pergola and canopies shade them in summer. This is the overhang principle from the diagram above at work: it reduces the need for heating in winter and for cooling in summer.

8) Soleta zeroEnergy One (FITS, Bucharest, Romania)

The Justin Capra Foundation for Inventions and Sustainable Technologies (FITS) built this prototype in Bucharest as the smallest model of its zeroEnergy range. Small House Bliss describes a 48 square metre (517 square foot) ground floor plus a 9 square metre loft under a gambrel roof of glued-laminated timber arches, with wood shingles, large high-performance windows shaded by timber pergolas, heat-recovery ventilation, LED lighting, rainwater collection and remote energy monitoring. The designers expected buyers to add renewable generation to reach net zero. The earlier claim that it saves “up to 45%” of energy could not be traced to a source and has been removed.

Is an eco house cheaper?

Usually it costs about the same or a little more to build and less to run, but the balance depends on climate, energy prices and how far the design goes. The cheapest gains are free at the drawing stage: orientation, window placement, overhangs and a compact form. Insulation and airtightness add some cost; solar panels, heat pumps and batteries add more and should be judged on local prices and incentives. Treat any fixed “percentage saving” with caution unless it comes from measured data for a stated climate.

Sources and further reading

For design principles, start with the US Department of Energy passive solar guide (cool and temperate climates) and Australia’s Your Home passive design guidance (which covers hot humid to cool climate zones). The project details above come from the publications linked in each section. Before building, check your local energy code and climate data; they govern insulation levels, glazing limits and ventilation.