last updated: 07/98
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In Europe, parks and forests are at a premium. People want to live amongst nature, but by moving to such sites, they often destroy the woodland paradise they are searching for. This paper discusses how a partnership was created between existing residents of a Swedish suburb, city authorities and new residents in order to provide additional housing whilst still protecting the environment.
Stockholm, with a population of several millions is one of Europes greenest capital cities. The Nacka nature reserve is an area of forest which stretches south-east from the centre of the city to its outskirts, providing an unbroken corridor of green for city inhabitants. Naturally, the suburbs adjoining this nature reserve are particularly popular residential sites.
One such suburb is Bjökhagen, which was built in the 1940s. With small-scale buildings, few roads, and connected by a subway to the city centre, the suburb is extremely popular - particularly with students and retired people. As such there has been high demand for the city to build more houses in the area, and equally there has been resistance by residents already living there.
In 1990 the city building office in Stockholm decided to allow building in a small wood called Understenhöjden (under stone hill) in Björkhagen. The new residences were to be in the form of five apartment blocks. This form, so obviously not in harmony with the natural beauty of the area, angered a number of people in Björkhagen. As a result, Mia Torpe, an architectural student formed EBBA, Ekologiskt Byggande I Björkhagen, an association to promote ecological building in Björkhagen. The associations aim was to develop an alternate plan for the new houses which would meet the needs of both the new and the current residents.
2. An Ecological Approach
EBBA quickly developed a radical new plan for a small village of ecological homes at Understenhöjden. They aimed to combine the self-building concept with user participation in the design process and the use of environmentally friendly materials and techniques. These were presented more concretely in the following list of aims:
Preserve existing nature as much as possible
- Avoid blasting away rocks and hills.
- Adjust buildings and roads for topography (and not vice versa)
Use water and other resources in an environmentally sensitive manner
- Catch rainwater in small ponds and streams
- Use water from local sources through a common pump-house
- Purify grey waste water locally (ponds, reed beds etc.)
Improve on nature where necessary
- Enrich soil to make space for garden cultivation
- Prepare areas favourable for building greenhouses.
Provide opportunities for community interaction
- Establish communal laundry, meeting/dining hall, and workshop
- Provide common play-spaces for children
Based on these principles EBBA designed a plan for 44 low-environmental-impact row houses to be built through the woods, connected to one another , and to a central communal hall by a network of footpaths. Roads were confined to the edges of the development. EBBA presented their proposals to the city authorities in 1993, expecting there to be many problems and much debate before their plans were approved. However, the city authorities were extremely impressed with the ideas of EBBA and within three months the plans were fully approved. The ecologic village was to be developed in a partnership by EBBA, the city housing co-operative HSB, and the self-build group Småa. By this time, rumours of the project had spread through the local area, and over 100 people had indicated a desire to live in the new development.
3. Building Ecologically
EBBAs next task, in its new role of partnership with the city, was to organize more detailed plans for the ecological construction, for example studying ways in which recycled material could be used effectively in the project. Members of EBBA travelled all over Sweden to learn from other attempts at ecological building. They also devised an innovative plan to ensure prospective home owners played an active role in the project. Anybody wanting to live in the development had to work ten hours each month in the design or building of the village or pay 300 Krona instead.
The design of the houses was finalised in co-operation with Bengt Bilén, chief architect of the HSB Although unfamiliar with the concepts of self-building and resident input into the design process, Bilén succeeded in drawing up a very popular plan for the houses. For harmony with nature he designed wooden-walled houses, with a floor area of 110 m2 on two levels. Although the outsides of the houses were identical, residents could choose the colours of their doors and of their windowsills, allowing a limited amount of self-expression. Inside the houses however, things were quite different. Bilén designed almost nothing except the position of structural walls. The partitioning of the floor space, and all other interior considerations were designed in consultation with the individual home-buyers.
In construction of the houses, every effort was made to use ecologically sound materials. The use of any metals or plastics was reduced to the absolute minimum, and materials were selected according to three prime criteria:their production should cause low environmental impact, they should expose residents to no health risks, and they should be easy to recycle. Thus, the walls at Understenshöjden were constructed from wood, and the 250 mm cavity between the outer walls and the internal plasterboard was filled with Ecofiber an insulating material produced from cellulose. The roofs were made from terracotta tiles, which were placed over several layers of cardboard used as insulation
Where metals and plastics were used in construction, there must be sound environmental advantages. Examples include the solar panels which have been installed in sections of the houses roofs, and the use of modern household appliances which are extremely efficient in their use of electricity.
In considering the heating of the houses in winter, the decision was made to use a district heating scheme, with all houses receiving hot-water from a central boiler located in the communal building. In line with the desire to make use of environmentally friendly technology, the boiler installed was designed to run on pellets recycled from waste paper. The hot-water produced is used in washing etc. and via a heat-exchanger is also used to warm each houses radiator system.
Waste treatment was considered throughout the planning of Understenshöjden. The toilets installed in each of the houses were designed to separate urine from solid waste. The liquid waste is collected in on-site tanks and sold to local farmers. It contains has very high levels of nitrogen and is suitable for use as a fertilizer. It is particularly valuable in Sweden owing to government taxes levied on artificial nitrogen-containing fertilizers.
The detailed plans for treatment of solid wastes and grey water (from washing etc.) could not be fully implemented at the site because of the geological conditions, but will probably be used at other similar sites developed in the future. The plan was for primary and secondary bioloicgal treatment, using bacteria to break down harmful compounds in the waste. Final clarification was planned to take place in a system of streams and ponds which would be lined with fruit trees, and which would ultimately have discharged cleaned, re-oxygenated water to the Baltic Sea. Unfortunately, the permeability of the local rock made the plan unfeasible for this site.
4. An Ecological Village Completed
The completed houses at Understenshöjden have been a huge success. The 44 row houses and the communal buildings can barely been seen amongst the woods, owing to both the way they hug the existing topography and the care taken during construction not to remove more than the absolute minimum number of trees. The communal house is well used by residents - allowing much social interaction - and all the houses are occupied by residents happy with their living environment.
In retrospect it is easy to see that building schemes such as Understenshöjden have much to recommend them. Among their main advantages are the following:
Development of an empowered community
As Understenshöjdens future residents played an important role in planning and building of their village, a strong sense of an empowered community has developed. The residents feel positive, and see how ordinary people can make real and positive contributions to the protection and beautification of the natural environment. This is a message they take throughout Sweden with them when they visit other communities planning similar developments.
Low Cost of Construction
Because the residents were also involved in the actual construction of their houses, building costs were significantly lower than they might otherwise have been. As a result, such ecologically friendly buildings are more available to people from all levels of society, not just the very rich. This also helps the community by making it more diverse and vibrant, occupied by people with similar ideas (environmental protection) rather than just similar backgrounds and financial conditions.
Achieving Ecological Benefit at a Reasonable Cost
A balanced amount of ecological technique is introduced at a reasonable price. The project clearly shows that a more ecological way of living is not necessarily more expensive, nor does it mean that residents have to live in less comfortable conditions.
The development at Understenshöjden has widely been regarded as a great success throughout Sweden and is now considered an ecological showcase. As the site is suburban, some of its successes can be reproduced in both rural and urban areas, and there seems to be a desire to attempt to reproduce those successes. The city housing co-operative (HSB) has been quick to incorporate the new skills it has learned through the development of Understenshöjden at the city-wide level. The project has shown clearly how ecologic building is the future for Europe.