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The URBAN FREE HABITAT SYSTEM defines a 3D space for any person to use. It may be placed in various parts of a city to provide persons with a place to relax, eat, sleep, etc.
The URBAN FREE HABITAT SYSTEM is a low cost system that could easily be initiated and implemented by local communities.
Once moored at a site in a city, the URBAN FREE HABITAT SYSTEM can be customized by the community to suggest a specific use. For example, it could be designated as a Caravanserai (a traditional Eastern inn for travelers), a meeting place for locals, or a noncommercial café and kitchen.
The structure can also be customized to meet local needs or weather conditions. Though the basic version shown on this page does not protect the users from rain, the structure could easily be covered with a tarp. The entire sphere could be insulated or insulated structures could be built and suspended within the frame to provide comfort in cold climates.
URBAN FREE HABITAT SYSTEM can be moved to a new site by one person, simply by rolling it like a ball. It can scale up or down and be used both inside existing buildings and outdoors. In areas with a high concentration of human activity, clusters of URBAN FREE HABITAT SYSTEM might be needed.


Traditional urban planning aims to inject cities with places for housing and culture of a predefined type. Little power is given to the residents to make decisions about their own environment. Consequently, the public space in most western cities and the urban landscape as such is dominated by concentrations of power and their commercial interests. All human needs are hijacked to make a profit. N55 propose the implementation of systems that would allow persons to design the public places they inhabit and share these places with others, regardless of anyone’s financial situation. Using such systems, people would be able to create free places to stay and meet, cook and eat, etc, where they are most needed. The URBAN FREE HABITAT SYSTEM is a result of a workshop by N55 at the Metropolis Laboratory in Copenhagen.


The main structure of the URBAN FREE HABITAT SYSTEM is a 3- frequency version of a geodesic sphere. Geodesic spheres are highly efficient structures that enclose maximum volume with minimal surface area and can be incredibly strong and rigid using a minimal amount of material. The spherical surface allows for this structure to be transported simply by rolling it, without special machinery or excessive force. Geodesic structures were studied and popularized by R. Buckminster Fuller in the late 1940’s. The current 3.5 meter diameter URBAN FREE HABITAT has been built using solid plain steel balls 4cm in diameter for hubs and 19mm diameter, 1mm wall plain steel tubing for the struts. Because the hubs are small spheres, the struts can be welded to them at the appropriate angles without a need for separate prefabricated 5- and 6- way connectors. A 3-frequency sphere requires three different strut lengths. The struts were measured and cut by hand with a cutoff disk on an angle grinder. Flat polygons (regular hexagons and pentagons) found within the geodesic structure were fabricated by measuring the required angles with a protractor and welding them together apart from the main structure.If the proper strut lengths and arrangement of struts is used, only one geometry is ultimately possible, so the structure
self-compensates for errors in angle measurements as it progresses. Diagrams for assembly and the proper ratio of strut lengths can be found from numerous sources on the Web. The version of the URBAN FREE HABITAT SYSTEM shown here has been equipped with a plant growing system, hammocks, cooking facilities, a toilet and a lamp.


The URBAN FREE HABITAT SYSTEM could be used for numerous specific purposes, as long as they are free for any person to use. For example, given the specific needs in a specific situation, a version of
the URBAN FREE HABITAT SYSTEM equipped as a greenhouse for growing food might be relevant. Other possibilities include a disco with a sound system, a schoolhouse, or an exercise facility. The open
3D space within the main structure allows for easy reprogramming to temporarily transform the system for other purposes. .

Technical specifications:

Basic module:
Diameter: 3.5 meters
Mass: 150kg
Component list:
210 meters steel tubing (19mm diameter, 1mm wall-thickness)
96 steel balls (4cm diameter)
Water tank
Polyethylene buckets

Aluminum version:

The URBAN FREE HABITAT SYSTEM can also be made from aluminum in a simple way as shown on the following photos. A standard aluminum tube is cut at the correct length, hammered flat at the ends, bend at a tiny angle and a hole is drilled at both ends. Assembling is easy with one single bolt connecting the struts at the joints.


Antwerpen, Belgium, 2009.

Showhow, Copenhagen, Denmark, 2009

In 2009 the Subvision exhibition in Hamburg made a copy of the URBAN FREE HABITAT
SYSTEM. After the end of the exhibition it was disposed of and found by till Wolfer and other
students at the HFBK. They restored it and used it as a DEMOTOOL in support of a squatted house.

iPeter madsen "Walking the structure".

By N55

Thanks to Peter Madsen, Henry and HALFMACHINE

Realized in collaboration with Sam Kronick

Financed by Metropolis Lab Copenhagen 2008

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