Carbon Copy

habitable buildings

The biophilia hypothesis maintains that humans have a built-in affinity for natural things, feeding our desire for keeping pets, climbing mountains, hiking in forests, and being where we can enjoy natural views. This attraction can explain why we like keeping plants in our homes and places of work, and presents an opportunity for architects and engineers to address the social aspects of sustainability at the same time as energy and health issues, through building design.

Having the right plants inside can directly improve air quality, but biophilia suggests that a whole range of design features could improve well-being through exposure to natural elements. In an introduction to biophilia in the Rocky Mountain Institute Newsletter of Spring 2004 [962 KB PDF], Corey Griffin writes:

Today, the technology and knowledge exists to create a building that touches the earth lightly during both construction and day-to-day operations. However, what has been often neglected by creators of low-impact “green” buildings is the need for spaces to be habitable. Occupants of built environments don’t want simply to work, play, eat, or sleep in a functional building. They want to be inspired, invigorated, comforted, and reassured by their surroundings. They want spaces that will make them more productive and healthy, and they want spaces in which they love to be—spaces that, as RMI’s Amory Lovins puts it, create “delight when entered, pleasure when occupied, and regret when departed.”

Biophilic design elements to achieve this could include:

• the use of dynamic and diffuse daylight,
• the ability to have frequent, spontaneous and repeated contact with nature throughout and between buildings,
• the use of local, natural materials,
• a connection between interior and exterior surfaces,
• natural ventilation,
• a direct physical connection to nature from interior spaces, and
• direct visual access to nature from interior spaces.

Griffin also mentions previous work on the hypothesis that provides some motivation for society's choices of landscape design and urban configuration, suggesting a link with our ancestral needs for food, shelter and places to explore. Perhaps our strong tendency towards urban sprawl is an instinctive response to the unnatural aspects of the concrete-and-steel urban jungle. If so, it's vital that attempts to increase urban density to support various aspects of sustainability should incorporate biophilic design elements, lest we become like caged tigers, sapped of life and spirit. OK, I'm being dramatic, but if we need that natural connection to be happier, healthier people, then we damn well better incorporate it in our sustainable cities of the future.

[Update on 3 Dec 2007: BLDGBLOG shows us the air brain, a high-tech version of "plant filters" to clean the air inside buildings. Nice and neat and... sanitized. Not at all like going out in the garden and getting your hands dirty.]

bring the jungle inside

At home and in the office, the best way to maintain air quality is to use plants to scrub toxins from the air. If you've recently installed carpets or furniture, chances are you can smell the pollutants, but they continue to be off-gased for ages. Products like particle board and plywood, often used to make shelves, desks and the like, give off formaldehyde, benzene and trichloroethylene. If you can't avoid these products, you can at least install a few plants that thrive on the gases.

burning down the house

Cape Town, 1985: Tyres are burning in the streets in protest against apartheid laws.

Cape Town, 2007: Tyres are burning in the streets to extract scrap metal that can be sold to dealers for recycling.

The air pollution is horrendous, and South Africa has now published draft waste tyre regulations for comment. There are at least two possibilities for disposing of the 11 million scrapped tyres each year in South Africa. One is to grind them for use in rubber carpets, athletic tracks and tarmac. The other is to burn them in kilns as an alternative energy source.

[Source: Cape Times, 12 March 2007]

low-cost household energy

Paraffin, coal and wood are fuels commonly used in South Afrian township homes that don't have access to electricity. But they are are relatively expensive, a common cause of house fires, and a source of respiratory problems. A company called GreenHeat in Durban is manufacturing an ethanol gel from sugar cane that is better than paraffin on all three counts. (Apparently the gel costs more than paraffin, but lasts much longer.) Sold with a stove, the gel is used either for cooking or heating.

Is this the end of the smog-fuelled Joburg sunrise?

walk it off

Planners regularly cite the importance of arranging land uses to reduce trip distances. For example, if neighbourhood shops are not isolated from residential areas, shorter distances increase the likelihood that people will travel on foot. Or if apartments are close to public transport routes, more can take the bus to work. There are many reasons for encouraging this, including the need to reduce the costs of widening roads and providing parking. The December 2003 edition of the Sustainable Transportation Monitor provides a new twist to this theme. Let me explain.

There are conflicting reports on why obesity is a growing problem worldwide. In general, our weight is determined by energy intake - specifically the consumption of fat in food - and energy expenditure through physical activity. Studies conducted in several countries suggest that energy intake from fat in food has declined, while body weights have been increasing. So we must be less active, right? Maybe, but is the focus of remedial actions making a difference?

In Canada, as far as health and exercise is concerned, the focus has been on organized activity such as physical education in schools. However, for some groups of the population, the rate of organized or deliberate physical activity appears to have remain unchanged or even increased, and yet body weights continue to rise. A possible explanation relates to the role of transportation - and the associated matter of urban form. Shorter trip lengths and the use of public transport increase physical activity, because they both can include walking.

One study has shown a correlation between average body weight and geographical area. People living in the core of Toronto, with mixed land uses and good access to public transport, have lower weights than those living in outer suburbs where car ownership and dependence are higher. The implication is that it is not just leisure-time activity that affects fitness, but transportation as part of everyday lives.