Introduction

The Iguana project consists of eight show homes with one company house and presentation space.
The original initiative came from Hendrik Gommer and Elsa Visser. When looking for an environmentally-friendly house in 1997 they kept drawing a blank. ‘Eco-friendly building’ did not mean much more than putting in a bit more insulation and a water-saving showerhead.
Iguana homes, like the iguana, look to the sun for their energy.

Objectives and target audience

The Iguana project demonstrates affordable bio-ecological houses constructed with a fully-environmental approach.

Financial Resources and Partners involved

The total cost of the work was € 2,100,000 (including photovoltaic panels) contribution with LIFE amounted to € 91,497.
The beneficiary is: De Groene Leguaan VOF (The Green Iguana), Middelweg 51, 8715 EV Stavoren, Netherlands

Process

There is less environmental pollution from the use of renewable and/or recycled materials, while shape is important as well (e.g. orientation to the sun).
A balance was sought by using solutions both cheaper and more expensive than traditional building methods. The result was a medium-budget home. Cheaper than normal was the wooden frame construction and the use of EPDM as the roofing material and larch as the facade coping. More expensive was, in particular, the use of cellulose, loam insulating walls and a solar greenhouse.
This mode of construction, with ‘breathing’ walls and vapour control/thermal buffer materials, can be sources of supply that are being used up.
Consumers, building contractors, project developers and authorities are insufficiently convinced of the feasibility and the advantages of bio-ecological houses. The aim of the Iguana project is to publicise the advantages of bio-ecological construction.

Results

The Iguana project has received considerable attention in the media. Just about every trade journal has carried an article on it. Three films have been made, including one by the EC. The Iguana houses have above all been a source of inspiration.
But not many have been built so far. The technical solution did not turn out to be the main problem in the short term. Creating a bio-ecological house is a complex business, too complex to be solved with a single project. The client, the architect, the estate agent, the provincial council, the town council, the project developer, the contractor, the subcontractor and the building worker all have to be advised and convinced. The construction of a bio-ecological house demands a great deal of know-how and the parties involved do not have enough. Accumulating know-how takes time and money and project developers want to invest too little. Every time a new contractor is brought in the same mistakes are made.
Lessons are learned only by practical experience.
Many model houses will therefore have to be built before really sustainable building becomes the norm.
Nevertheless, the Iguana project can be called a success. This has helped and is helping to shake up the building world.
The Iguana project is still being studied (SBR, SEV, TNO-hout, NOVEM) and reports on the Green Iguana still appear very regularly in newspapers and/or trade journals. An Internet publication (www.leguaan.nl) and a subsequent article have ensured extra attention for sustainable building in Friesland.
The typical shape of the house points to the need to orient new houses to the sun. Building solar-oriented houses led to as many as 16 different PV systems being installed on Iguana houses, making the Iguana project a testing area for PV systems in existing structures. So much experience has been gathered that the Green Iguana can now be said to be an authority on photovoltaics in existing buildings. This in turn has led to the involvement of the MegaPV design office in the Iguana project, which in the coming years is going to carry out a practical experiment on the ‘large-scale introduction of PV’ in cooperation with Novem, Essent and the city councils of Leeuwaarden, Groningen and Assen (www.megapv.nl/mega). One of the aims is to bring in environmentally-neutral construction in the wake of the introduction of PV.

Critical Success Factors / Challenges

In the Netherlands and even in other parts of Europe the Green Iguana has more or less grown to become a symbol of environmentally-neutral construction. It will therefore focus attention for years on the need for environmentally-neutral construction. Thanks to the contributions of LIFE, IPR, Novem, Friesland Province and SEV it will now be able to stand on its own two feet and develop new initiatives.