Here is an interesting idea from Dezeen for a prefabricated house; Tokyo architects Atelier Tekuto (known to TreeHuggers for a really skinny house) are developing an aluminum structural system that also works as a radiator for heat, and a conduit for electrical and plumbing.
The architects note that "Although the manufacture of aluminum requires enormous amounts of electricity when being manufactured, the quality of metal stays stable and it’s perfect for practicing the ‘3R’s’: Reduce, Reuse, Recycle. Recycling aluminum requires only 3% of the energy to produce it. Changing the great amount of architectural waste into aluminum and recycling it results in reduction of environmental damage in a long run."
It is designed for the harsh, cold conditions of Northern Japan: "It is our task to provide a comfortable residential environment for those who live in this severe northern climate under the five principles of the aluminum project. We propose this project as an attempt to introduce an aluminum structure which also works as a thermal radiator device and reduces the running costs zero, using natural resources.
The Five Principles of Aluminum Project:
1. aluminum structure
Having done many studies on the aspects of unit strength, economy, execution of work, we came to a transformed deck plate which makes columns, walls, beams and slabs with one simple mould. This ring-like structure, consisting of the extruded aluminum, becomes a basic structure of the aluminum house. The joint is fairly easy to assemble for most carpenters and engineering builders.
2. aluminum structure, isolated from the external environment
The thermal conductivity of aluminum is about three times higher than that of steel and it’s likely to stimulate condensation and heat loss. Usually this occurs when aluminum is exposed to the severe gap between outside/inside temperature, meaning that if we could isolate the aluminum structure from the outside air this problem can be solved.
3. aluminum structure as a thermal radiator device
Following the rules listed above results in better thermal conductivity and better thermal radiation and reflection conditions. Pipes inside the hollowed-out aluminum molds allow hot water or cold water to circulate within the ring-formed structure.
4. keeping the original texture of aluminum
Aluminum has a dull glow and allows a rich silvery look when not anodic oxide coated and has a decent thickness. This distinguished feel as a material can not be achieved with other materials such as wood, steel, nor concrete.
5. structure functioning as an equipment space
The hollowed-out aluminum moulds not only work as a radiator which circulate hot and cold water but also as a pipe for the electric equipment system. After the construction of the pipe arrangement and track layout, removable aluminum flat bars get installed allowing continuous aluminum surfaces to appear and making it easy to maintain. ::Dezeen