Apr 4, 2009

Solutions to the Housing Crisis IV

Build with what? -- The example of corrugated iron.


Before I move onto other issues in regard to streetscape and suburban refit I want to refer you to these two house designs by the Melbourne architect firm of Designology. The house above is The Convertible House



Award winning alternative dwelling that is ecologically sustainable, durable, low cost,flat packed (or semi-prefabricated), low embodied energy, high security,storm & fire resistant for a relatively remote rural location
The example -- right -- is the same company's off grid house.

I'm sure there are thousands of permutations on such themes. Any Google search of "off grid housing" or modular kit houses, preFab construction, panelized, manufactured housing (example) will deliver a massive array of design and material options.

And if you go visit Container City you get ready made use of shipping containers!:



The Container City™ system uses shipping containers linked together to provide high strength, prefabricated steel modules that can be combined to create a wide variety of building shapes and adapted to suit most planning or end user needs.This modular technology enables construction times and cost to be reduced by up to half that of traditional building techniques while remaining significantly more environmentally friendly.
While this plethora of options is perhaps endless, the features I think warrant consideration are:



  • These buildings are prefabricated and factory built.
  • The design lends itself to portability and recycling such that many of these houses can be shifted elsewhere on the back of a truck or disassembled and the materials re-used in another build.
  • The best of them use modern materials that are considerate of the Carbon Dioxide created in their production.
This last point is important. There is a habit in the environment movement to prefer a certain organic preference in proselytizing the eco friendly house we must have. So it's supposedly has to be made from straw bale or rammed earth construction on a cement slab. That's not necessarily the case.



An Australian system, BMAS (Building Material Assessment System), based on life-cycle analysis, has been developed to compare the relative ecological impacts of various types of wall, floor and roof assemblies. Some indicative results are as follows (NB: High numbers indicate greater environmental impact; lower numbers indicate lesser impact):

WALLS




Timber Frame, Plasterboard 7.2
Steel Frame, Plasterboard 7.4
AAC Blocks - rendered 20.6
Clay Bricks - rendered 49.

FLOORS




Timber, Brick Piers, Footings 41.9
Concrete Raft Slab 74.4

ROOFS




Timber Frame, Corrugated Steel 5.2
Timber Frame, Terracotta Tile 20.6

This is where the corrugated iron overlay in the top image example above -- The Convertible House -- makes so much ecological sense despite what may be first impressions. In fact many modern industrial building materials -- except bricks, cement, mortar -- combined with wood , are climate change low impact.What they don't offer as matter of course is thermal mass.

Inasmuch as I have any building knowledge the irony is that the historical preference for wood and corrugated iron construction in Australia is a lot more environmentally friendly than the modern preference for bricks and mortar.

This brings me around to a conversation I had with Roberto Perez , the Cuban permaculturalist who Green Left Weekly helped tour here during 2008. Perez was impressed with the massive potential corrugated iron had for housing in Cuba as part of the green revolution he was playing such a key part in. He had to come here for its relevance to register because Australia is, as the wonderful book Corrugated Iron: Building on the Frontier insists "the spiritual home of corrugated iron".

If we can get over the long term disdain for the Nissan Hut (right)-- and the suburb in which I lived was settled first by military personnel in Nissan Huts during the Second World War -- or the dismissal of the tin shed as an out building; in our planet of slums, tens of millions are housed in corrugated iron throw togethers using recycled sheeting.( Cape Town image- left).

In terms of where we are at now in regard immediate options :"It is quite possible in all parts of Australia to construct a 'house with no bills', which would be comfortable without heating and cooling, which would make its own electricity, collect its own water and deal with its own waste...These houses can be built now, using off-the-shelf techniques. It is possible to build a "house with no bills" for the same price as a conventional house, but it would be (25%) smaller."Brenda and Robert Vale.

The materials issue is a major concern for one of Australia's greatest architects, Glenn Murcrutt ,who is an innovator in the application and use of corrugated iron in building design and construction:



GLENN MURCUTT: It is about environment. But it's taking into account where materials come from, the true costs, to understand that timber is a very marvellous material. It's a renewable resource. It takes only five megajoules of energy to process a kilogram of timber. It's just marvellous. A kilogram of aluminium, for example, takes 143 megajoules of energy. Hugely different. So it allows you to proportion the use of materials in a building, put things together in a way you can pull apart and reuse them. That's a... that's a really important area, so we don't have the loss of materials. I've been thinking about that for a long time.





A Murcutt design

While this may be true the challenge is not to proceed one house at a time but to set in place broad scale adjustments that embrace whole neighborhoods -- regardless of where they may be located -- so that new housing can be constructed and all current ones retro-fitted as part of a collective rather than an individual solution while making radical adjustments to energy inputs.

The Socialist Alliance tackled this option in its campaign for the Newcastle City Council when it was argued to take the whole of Newcastle off the grid.

As for what may be the key tasks for retro fitting already existing housing stock, the NABERS rating scale is a useful guide to where individual dwellings may be at. Test out the house you live in.

The story so far: