Building a house for easy breathing

Simon Fraser University physician and researcher Dr. Tim Takaro and his colleagues at the University of Washington and the Seattle Housing Authority have specially designed 35 Seattle homes for people with asthma.

The homes — which were built expressly to reduce asthmatic attacks — are the first of their kind in North America, and if they perform as well as Takaro hopes they do, they could become prototypes for “green” homes of the future. They were built this year by the U.S. Department of Housing and Urban Development in the Seattle district of High Point as part of an environmentally advanced development of 1,600 homes now occupying what used to be a run-down housing complex for Boeing workers. They cost about $140,000 US each to build, range in size from two to five bedrooms, and have been placed randomly throughout the development so no one living in them will be able to identify which is a “Breathe Easy” house and which isn’t. What makes them special, says Takaro, who has a particular interest in respiratory illnesses, is their emphasis on reducing the stuff that can trigger asthmatic attacks — mould, dust mites, dust, roaches and rodents. And the best way to do that, he says, is to keep them dry. “The envelopes of the houses are extremely tight so they’re extremely unlikely to leak,” Takaro said in an interview. “In the course of their construction, special care was given to keeping the materials dry too. And once the framing was done, the houses were dried out with fans and blowers. So a lot of effort has gone into keeping moisture out.” Because it’s moisture, he says, that allows for the breeding of potential allergens.

On a wet day, an average Vancouver house has an 80-per-cent humidity level.

To keep allergens at bay, the humidity level has to be 70 per cent or less.
That’s why the 35 Seattle houses were built with the following features:
**Insulated windows with next to no heat exchange.
**A five-centimetre carpet of insulating foam between the concrete foundation and the floor.
**Floors made of a specially designed linseed byproduct that doesn’t emit such organic compounds as benzene and formaldehyde — compounds that can trigger asthmatic attacks.
**No carpets since they can be reservoirs for allergens.
**Built-in ventilation systems that refresh the air in the house every three hours.

The idea is that until next summer, Takaro and his U.S. associates will collect data from the residents of these houses to see if and how their lives have been changed. What he hopes to see is a significant drop in the number of times an asthmatic child has to use his or her inhaler and/or visit a doctor. So far, anecdotal evidence has been promising. “People say they feel much better,” Takaro said. “They say they are able to sleep through the night.” Maria Pryor certainly is sold. “It’s a wonderful program,” she says. “I hope it helps other people as much as it helps me and my son.”

Once more precise measurements are taken, Takaro hopes to present his data to governments and other agencies that fund health care to try to convince them of the importance of building environmentally healthy homes. “You could go to builders and designers as well, look at the building guidelines, and see if these guidelines can be changed to incorporate some of these advancements,” he said. Because, he adds, asthma is on the rise. Thanks to a dramatic increase in the last 20 years, about 10 per cent of North Americans now suffer from the disease, and no one knows why. “It must be an environmental cause because it’s not genetic,” said Takaro. “The question is: What aspect of the environment is causing it? We don’t know.” What is undeniable, he says, is the value of prevention. “If you control the environment, for some asthmatics, they are to all intents and purposes cured. “Can we prevent someone who is genetically pre-disposed to asthma from getting it? That’s better than a cure. That’s really our hope.”

(prepared by Nicholas Read/Vancouver Sun)