IF SOMEONE ASKED you to live in a chemical factory, you'd refuse. Yet, considering that our homes often contain a toxic cocktail of volatile organic compounds, formaldehyde, vinyl chloride, xylene, isocyanates and glycol ether, a chemical factory may be a safer alternative.
Because the air in our homes may be up to seven times more polluted than the air outside, design that tackles the problem can have a major impact on our health and well-being, particularly when it comes to allergies.
Architect Caroline Pidcock says it's time we concentrated on what we're putting into our homes, because this is where we nurture our families. 'It's worth spending more time and money putting better quality, less toxic materials, finishes, and furniture into our homes,' Pidcock says. 'After all, how can you put a monetary figure on health and family?'
Then there are the household irritants and allergens that precipitate asthma.
Janet Rimmer, respiratory physician and allergist, says that for many allergy sufferers indoor allergens can pose a major health problem.
'These allergens include house dust mites present in all soft furnishings, and on cats, dogs and cockroaches,' Rimmer says. 'Moulds also pose a potential health problem both to allergic and non-allergic people. Although mould is generally visible and usually detected by a musty smell, other allergens may not be so easily detected.'
According to Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO), there are steps we can take to make our homes safer from harmful chemicals and allergens. It recommends four simple steps: eliminate, ventilate, separate and absorb.
It's important to remove the source of the problem through product selection and design. When building or renovating, try to use materials with low emissions. Ask your builder or architect to select products that have been pre-dried, use water-based solvents or those with a zero or low volatile organic compound (VOC).
A good place to start are traditional materials that tend to have negligible toxicity levels. These include beeswax polish and linseed for wood finishing, lime wash for walls, vinegar and lemon juice for cleaning and herbs for pest control.
Also, choose products with low pollutant emissions. These include: termite barriers made from granite or steel (rather than chemicals); hard flooring such as ceramic tiles; timber finished with plant-based oils or waxes (instead of polyurethane); linoleum or cork (glued with natural rubber latex); rugs on hard surfaces (rather than carpet); and plant or mineral-based paints (or a low VOC water-based paint).
When it comes to allergens, carpet is often the worst offender. That's because it usually contains dust mites that can't be completely removed by vacuuming. Consider replacing your carpets and rugs with wooden, tiled, cork or linoleum flooring.
However, if you must have carpet, use a low-pile synthetic and clean it weekly with a vacuum that incorporates a Hepa filter. One of the most popular vacuum systems, the Dyson range, uses Hepa filters with Bactisafe screen traps that kill bacteria and mould on contact.
The furniture in your home can also release pollutants and irritants for many years. It's best to choose leather or cloth upholstery, which tends to house a high population of dust mites.
Timber and metal are also good because they're easy to keep clean. However, the types of solvents used in their construction can often release harmful toxins.
Michigan-based manufacturer Herman Miller, famous for producing modernist furniture such as the Eames Lounge Chair and Ottoman and Nelson Platform Bench as well as office classics, including the Aeron and Mirra chairs, is also known for environmentally responsible manufacturing. 'This means harmful adhesives are replaced with water-soluble glues and foam-upholstery padding produce low to zero VOCs,' says Herman Miller spokesperson Alan Boyd.
Australian designer Matthew Butler also has a commitment to green furniture. His Zaishu is a flat-pack, portable seat/ table/box, that can be slotted together in seconds. The Zaishu comes in a number of limited-release patterns by prominent modern artists from around the world, including the late wallpaper-designer Florence Broadhurst.
Butler says the veneer from which the Zaishus are constructed uses the lowest glue content possible, and there's no off-gassing. 'We also use water-based paints,' he says.
All of which should be of interest to indoor-air sufferers, who might be plagued by a range of problems, including headaches, fatigue, coughing, sneezing, dizziness and eye, nose, throat and skin irritation.
Estimates by the CSIRO suggest that occupants of new homes may be exposed to many times the maximum allowable limits of some indoor air pollutants and that little is known of the effects on the human nervous system.
The bedroom is a notable culprit, especially because we spend a third of our lives in this room. Simple precautions include replacing curtains with roller blinds (they collect less dust), installing hard floors, reducing clutter, keeping out pets, using mite-resistant pillow coverings and regularly washing bed linen in hot water (above 55 degrees Celsius). Latex mattresses should also be considered.
It's important to allow plenty of fresh air to circulate throughout the home so pollutants don't accumulate to unhealthy levels. An indication of poor ventilation includes window and wall condensation, stuffiness, and mould on shoes, books and other household items. One of the best ways to control air-flow is to use glass louvres to facilitate cross-flow ventilation.
Louvres enable an entire wall to be opened or closed, depending on weather conditions. And because they can be tilted at various angles they allow home owners to control the direction of the breeze.
This is the principle of separating problem materials (that is, those that emit irritants and other pollutants) by using barriers or sealers. Laminates can be used to seal wood-composite products. And it's hard to go past paint or varnish as a sealer; just remember to choose a low-irritant variety.
Also consider keeping compost heaps and bins away from the house because they're a major source of fungal spores. These may be good for the garden, but they're not good for asthmatics.
Among the easiest and cheapest ways to keep air in your home clean are indoor plants. They absorb the nasty stuff such as VOCs and also filter dust and dirt, and emit oxygen.
According to studies by Nasa, the top 10 indoor plants for healthy living are: the areaca palm, lady palm, bamboo palm (great for the removal of benzene, trichloroethylene and formaldehyde), rubber plant (the best overall for removing chemicals from the air), Dracaena fragrans, philodendron, miniature date palm (very effective for the removal of xylene), Ficus Alii, Boston fern, and peace lily.