Puchenau:
Puchenau II Garden City

EA.UE

,

Country: a) Western Europeb) Austria
Language:
Type: Project, 1
Area: City/Town, < 20,000
Actors: Local government, Economic sector
Funding: National government, Other
Topics: Architecture and construction
Building materials
Housing (and new settlements)
Objectives: Improve living conditions
Increase district heating
Increase green areas
Increase use of clean technology
Increase use of renewable resources
Reduce car mobility
Reduce energy consumption
Reduce land usage
Reduce noise impacts
Reduce resource consumption
Instruments:

Abstract:

Puchenau Garden City is a settlement near the city of Linz which has been growing steadily since the late 1960s to the current total of 1,039 residential units. Although this project was not conceived explicitly in terms of an ecological settlement, essential basic principles in ecological construction have been implemented in the major urban scale development.

Background and objectives

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Project description

"Puchenau Garden City Settlement" is the name of what is now the municipality of Puchenau's largest settlement. The garden city settlement has continued to develop here since the sixties, and has added approx. 2,400 inhabitants to the town, bringing its present population to around 5,000. The Puchenau Garden City (henceforth also "Puchenau" for short) has had an unusually long and continuous planning and building period, spanning over three decades.

The Puchenau Garden City settlement combines urban, high residential density habitation with the "ideal housing form" for the majority of the population (who wish to live in a single-family unit). By building cost-efficient, single-family dwellings in high-density low-rise buildings, and a cost-efficient, multi-storey apartment building where affordable living space was created for a large part of the population within the framework of social housing. By minimising private space consumption, providing an optimised resource-efficient infrastructure and traffic system, keeping noise pollution and hazards in the settlement to a minimum, and by the energy- and cost-efficient use of solar energy over a long planning and building period, a future-oriented residential settlement within easy reach of the town has been created. Although in self-portrayals and descriptions the project is not explicitly described as a "sustainable settlement", it is nonetheless true that basic fundamental principles of sustainable settlement design have been implemented here on a larger scale. Although certain aspects of the implementation of the settlement do not live up to current standards of state-of-the-art sustainable architecture (the choice of insulation material for example), some key principles have been realised here in an exemplary way.

Initial situation and stages of development

Puchenau is a small autonomous municipality in Upper Austria with a relatively long history. Situated directly next to the Danube, it is only three kilometres away from the western part of the city centre of Linz. The housing market of this city was characterised during and after the Second World War by severe shortages. The nearby municipality of Puchenau was, and is therefore, an ideal site for housing.

A site in the southern centre of Puchenau, which opens on to the water meadows of the Danube, presented itself as an appropriate location for this project. The development of this area has been a subject of discussion since the fifties. The initial development design for this site had envisaged six-storey uniform development in identical large housing blocks. In contrast to the spirit of the times in mass housing, which was characterised by a boom of the high-rise, this concept was fundamentally transformed at the beginning of the sixties. The concept of the Puchenau Garden City was formed.

Participants

The visionary urban design ideas of the architect Roland Rainer, who was already renowned in 1960, played a crucial role in establishing the guiding principle and objectives of the Puchenau Garden City. The open-mindedness of the ‘formal participants’ towards these very unusual development ideas was also of great importance. One of these people was the then mayor, Derndorfer (a farmer with "a common-sense attitude to buildings and nature", according to the opinion of one participant), and another, the then director of the Linz branch of Neue Heimat, Friedrich Kühberger. The Ministry of Building and Technology also played a significant role; later financing the project, promoting it as a demonstration project, and facilitating the parallel research. The convergence of these visionaries, initiators, and developers from the spheres of politics, innovation, planning, and developing meant that key decision-making people and institutions came together to initiate a project which, at the time, must have seemed an extremely brave venture.

Guiding principle and objectives

The idea behind the Puchenau settlement is inspired by old European, oriental, and Asian city structures, and by the European Garden City Movement. It does not, however, get entangled in the whole complex of related ideas or knowledge, in some cases, developed over thousands of years and incorporated in individual ideologies; such as the anti-urban ideologies of the Garden City Movement. The essential guiding principle for the Puchenau I settlement is tangible in its comprehensive approach to urban design and the environment, and in the fact that it is affordable and suitable for mass housing. In a certain sense, the guiding principle is embodied in the philosophy of the architect. This philosophy combines the experience of thousands of years of urban development (which traditionally necessitated lower space consumption, proving that this is also possible today), with current knowledge of newer technologies (for example solar-powered domestic water-heating). It also embodies the new broader demands on architecture and urban design resulting from the prevailing social, demographic, economic, and ecological conditions. All of these ideas combined lead to long-term solutions to the issues of urban design and the environment.

A significant aspect of the guiding principle behind Puchenau is concerned with creating a "people-friendly settlement," as well as with protecting resources (above all in minimising or reducing space, material, energy, and therefore capital consumption). A further aspect of this principle addressed the combination of city structures (high-density urban development for example) with small-scale structures, such as single-storey buildings and the creation of individually designable and useable open spaces. The aspect of the ‘experiment,’ of ‘learning by doing,’ is also significant, such as in the testing of different solar energy systems.

The intention behind the Puchenau Garden City settlement was to plan, realise, and monitor a settlement which:

Implementation

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Planning process - ecological concept

The Puchenau Garden City Settlement consists of two parts: Puchenau I and Puchenau II, which are built with different yet integral building methods. The two parts will be separated by a green stretch of land and a small infrastructure area. The two parts of the settlement a site that is roughly 1.5 km in length and approx. 100 to 150 m in width. Some of the buildings are built as high-density, single-storey buildings and as two-storey row houses; some as rented housing built up to a height of four-storeys. Roughly the same number of rented apartments as single-family units and condominiums were built. The settlement was built as a demonstration project and the dwellings were subsidised to a great extent with public funding.

Urban design

The Puchenau I settlement, which comprises roughly 290 dwellings, was commissioned in 1962, and completed between 1967-1969. The basic solutions to the objectives followed on in the later settlement of Puchenau II were already evidenced here such as; space-efficient building and lifestyles, pedestrian-zone residential areas, use of passive solar energy by the consistent south orientation of the buildings, etc. The experience gained by creating this settlement (based on expert opinion and interviews with residents on the issue of living environment satisfaction) were channelled into the planning of the far larger Puchenau II settlement. Complaints in Puchenau I that the settlement's walkways and walks were too narrow for daily use could be taken into consideration in the planning of Puchenau II. Puchenau I then, had something of a pilot character for Puchenau II.

The guiding principles and objectives behind Puchenau II have now been put into practise to the greatest extent possible. They are perceptible in the overall urban design solution. To the north, the traffic-free settlement is protected against traffic noise from the adjacent federal road by a multi-storey building which acts as a sound barrier. The development is consistently south-oriented and inclines toward the Danube water meadows so that the south-facing living spaces and bedrooms, loggias, yards and gardens are acoustically protected and receive optimal sunlight. The underground car parks below the multi-storey buildings accommodate the residents' cars. Easy access to the settlement is provided by a system of walkways for pedestrians and cyclists, which has a main east-west walkway and various byways. Many features of the Puchenau settlement exemplify high-quality urban design such as: the green stretches, some with natural running water, the proximity to the Danube water meadows, and the high-density space-efficient development sited close to nature in a park landscape all converge to make the settlement a "landscape of town-garden-nature rolled into one."

The Puchenau project is also turning out to have an influence on the external infrastructure. As the high-density development is in a rural location, but within easy reach of the city, it has led to the planning of new rail and bus lines, including public transport services within the framework of the regional Austrian transportation association. Efforts are being made to include Puchenau in the core area of the nearby Linz public transportation services, and to develop the existing rail connection into an extension of Linz’s urban train system.

Dwelling layouts and Baubiologie

Thirty-four dwelling layouts for various forms of housing, from single-storey to multi-storey buildings, were designed for Puchenau II. Layouts for buildings and dwellings were based on the experience gathered from Puchenau I but incorporated designs that took this further. The different dwelling floor plans, the garden courts of the single-storey atrium houses, and the two-storey single-family row houses offer a wide spectrum of housing forms to meet housing needs within the settlement for nearly every stage in the life of the occupants, from the ‘single's household’ to the large household with children.

The dwelling layouts, including the private open spaces allocated to each residence, were designed with particular attention to space-efficiency. Whereas the largest atrium houses with a total of 135 square meters of living space were built on a 271 square meter-sized lot, the smallest two-storey single-family units of 102 square meters of living space required only a 105 square meter lot. Of particular consideration was the use of passive solar energy. Optimal solar access to the rooms in summer as well as in winter was ensured by the layout of the massing, the floor plans, the siting of the buildings, and the positioning and orientation of the windows. Each type of building is designed to take maximum advantage of passive solar energy.

State-of-the-art features of Baubiologie were incorporated where feasible. Brick masonry and wood were predominantly used, and in parts cork. The aim of installing only wooden windows was also realised. Types of mineral wool prevalent at the time - but now considered controversial - were used as insulation material, although more environmentally-friendly insulation was also used.

Energy systems and infrastructure development

Basic principles of passive solar energy use were already applied in the older part of the Puchenau I settlement, and the buildings here were supplied by a district heating plant. Heating in Puchenau II was augmented by active solar energy systems. In most of the Puchenau II settlement, solar collectors for water-heating are successfully utilised from May until September. The initial use of solar collectors for heating purposes, tested in eighteen buildings with various systems of radiated warmth (under-floor space heating, air heating, blower convectors), had to be abandoned eventually because of technical problems with the controlling systems. This in turn led to overly high costs. Studies done in recent years showed that the consumption of natural gas for space heating was above the target values, in spite of the extra attention given to an efficient construction type and a south-orientation of the structures. The 290 units in Gartenstadt I consumed about 600,000 cubic meters annually and the 255 units in Gartenstadt II used about 537,000 cubic meters per year. Nonetheless, an average energy savings of roughly 18% of gas, the primary energy medium, was reached in these "fully solar buildings". In some cases up to 70% of the energy required for domestic water-heating and up to 25% of space heating needs could be met by solar energy.

The great majority of the buildings in Puchenau II are equipped with gas-fired boilers for space/water heating, including condensation boilers. The insulation measures here go far beyond the standard minimum: a factor which also contributes to energy conservation. The walls were all super-insulated and all larger windows were triple-thermopane-glazed, rather than double.

The space and resource-efficient development system, domestic road infrastructure, and supply and sewage disposal services are also worthy of note. The space and resource-efficient concept of the entire settlement allows a garden city of ‘short distances’. These ‘short distances’ were also realised for the utilities and infrastructure, including sewage disposal lines. The simple pavements of the walkways and bicycle paths, and the nearby utility links allow for far easier maintenance and repair work - both on the system of walkways, as well as on the services that generally lie underneath them - than can be the case in residential areas with more ‘generous’ infrastructures. The comparison of savings (cf. ‘Financing’ section) in terms of civil engineering work, material costs, service rights to be obtained, and finally capital required for the construction and upkeep of the supply and sewage disposal services of Puchenau II in relation to the rest of Puchenau (Puchenau North) becomes even clearer through the example of the layout of the sewer network and electricity supply system (cf. pictures).

Building phases

While Puchenau I was built in the relatively short building period of about two years at the end of the sixties, the building of Puchenau II stretched over a, so far, twenty-year-long building process. The project, consisting of ten building phases, will be completed within the next two years (2001). This moderate building process simply happened, rather than being planned as a result of the granting of subsidies. The numerous building phases had a positive effect on the end result and on the organic growth of the settlement. Also the long planning, building, and controlling time frame made it possible to implement necessary planning corrections.

In order to build the proper number of apartment and building types to correspond to the immediate demand of prospective users, the "Neue Heimat" built demonstration buildings in Puchenau II before actual building began. The architect furnished them to suit each individual type of building, making them accessible to interested parties. The visitors' reactions to these demonstration buildings and floor plans were decisive in determining how many dwellings of each type were built in the end. ‘Neue Heimat’ was in charge of the site management of the settlement and the architect was in charge of ‘artistic direction’.

Social concept and quality of life

The residents who shared the responsibility for the Garden City Puchenau experiment are the group most important for the success of the settlement, since in the end its success stands or falls with their positive attitude towards it. Thus, the ‘checking’ and controlling of the experiment by experts, and above all by residents, was on an equal par with the innovation involved in the project and its implementation. The general view was that ‘good communication’ existed between the responsible parties and the residents (or co-responsible parties) in the planning phase as well as in the realisation of the project. The motivation behind acquiring a house or apartment in Puchenau II was and remains the high quality of living and the low building costs. It must be said that user participation in the designs only applied to the dwelling interior (changes to walls, floors, etc.). No concept for the social organisation of the residents has been developed. However, the nature of the settlement lends itself to social self-organisation. Interest groups have formed, for example, and neighbourhood street parties are organised for the expanding neighbourhoods.

Satisfaction of the occupants environmental living conditions in Puchenau II Garden City was rated in 1984 at 90% with "very satisfied" or "satisfied". The single-storey buildings were by far more popular than the two-storey ones. At that time complaints primarily concerned the lack of infrastructure facilities. The new community centre to the east of Puchenau I, which now has a new church and a new music school, seems presently to be gradually drawing Old Puchenau and the garden city settlement together.

In the meantime, a local identity in the garden city is emerging. Consequently, the Puchenau Garden City settlement has become a district that combines city structures with "human-scale" architecture, providing private spaces and yet creating conditions conducive to social life and the formation of social communities.

Financing and resources used

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The majority of the apartments and houses were constructed within the framework of the subsidised housing programme. Whereas some of the homes in Puchenau I were initially financed in private sector housing, the planning and building of Puchenau II was able to fall back on the new subsidisation regulations. These regulations have earmarked subsidies for high-density low-rise buildings since 1978, for underground car parks since 1975, or for alternative energy-generating facilities for space and domestic water heating since 1978. Only because of these and other new subsidisation regulations was it possible to implement the comprehensive concept of Puchenau using funds designated for subsidised housing. On the whole, the financing of privately-owned apartments and houses was broken down into 40% public funding, 40% loans and 20% private resources. The rented housing owned by "Neue Heimat" was built with 75% public funding and 25% private resources.

A comparison of the costs incurred during the realisation of Puchenau II with those incurred in the rest of Puchenau showed clearly that it was feasible to build alternatives to the single-family unit like those realised here (atrium houses, row houses, and condominiums), and to do so within the tight financial restrictions of subsidised housing. In the first half of the eighties a square meter of living space in Puchenau II, with its thirty-four dwelling types, could be built for an average total cost of S 9.975 (approx. 1,450 DM). A cost comparison between the road infrastructure and supply system of the Puchenau II Garden City settlement, with its space and resource-efficient services concept, and that of old Puchenau, reveals that the costs of Puchenau II were considerable lower. The comparative study calculated that the road infrastructure and investment costs for car-accessible promenades, playgrounds, covered walks, walkways, green spaces, and diverse streets in Puchenau II were S 48,000 (roughly 7,000 DM) per building: less than a third of those of "normal development" in the area, which were calculated at S 166,000 (roughly 24,170 DM) per building. The comparison of the water, electricity, gas supply, and sewer services investment costs is even more revealing. If the existing services of old Puchenau were taken as a basis, the cost of water, electricity, gas supply, and sewage disposal services would reach an average of S 319,000 (roughly 46,500 DM) per building, whereas the space-efficient garden city settlement required only about a quarter of that sum (S 75,000, or roughly 10,900 DM).

Lessons learned And transferability

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The Puchenau Garden City is a good example of the fact that a large part of ecologically conscious urban design consists of incorporating basic user-oriented principles of urban design and sustainable architecture. This settlement demonstrates that even with a particularly space and resource-efficient concept, homes in the form of atrium and row houses as well as condominiums and rented dwellings, can be built cost-effectively for a wide section of the population without neglecting architectural quality. The high level of satisfaction with the environment in the settlement is due primarily to its high quality and cost-efficiency, as most of the dwellings were built within the framework of social housing.

The successful implementation of the planning is mainly the result of a holistic approach and of the enduring commitment of the small number of participants. The clear approach, careful planning, and long planning and implementation period of nearly 30 years have allowed the settlement to expand organically. The experience of building and living there has had time to be reflected upon, and the homogeneous settlement with a differentiated population structure and a unified phenotype attests to the success of the project.


Source of Information

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Communication with: Mayor Mag. Josef Almesberger. Puchenau, 1998.

European Academy of the Urban Environment (ed.); D. Kennedy, M. Kennedy (a): Designing Ecological Settlements, Berlin 1997

D. Kennedy, M. Kennedy: Zukunftsweisender ökologischer Siedlungsbau in Europe, Kissing w.y.

Statistical Information

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Puchenau II comprises 750 units (Puchenau I had 240 units)

Construction period for Puchenau II was from 1979 onwards

Puchenau I was 1967-69

Contact:

Name:Almesberger
Firstname:Mayor Mag. Josef
Telefon:++43 / 732 / 22 10 55 - 0
Telefax:++43/ 732 / 22 10 55 - 11
Address:Kirchenstraße 1
4048 Puchenau
Austria

Cities:

Puchenau :

The Austrian local authority body is located 4 kilometres from Linz in Upper Austria. It has been a member of the Climate Association (Klimabündnis/Alianza del clima) since 1996 and has undergone extensive structural changes in recent years. Whereas approx. 40% were engaged in agriculture in the middle of last century, the figure is now only 1% of the population.  

Population:

5000

Project was added at 11.08.1998
Project was changed at 05.03.2001

Extract from the database 'SURBAN - Good practice in urban development', sponsored by: European Commission, DG XI and Land of Berlin
European Academy of the Urban Environment · Bismarckallee 46-48 · D-14193 Berlin · fax: ++49-30-8959 9919