Once considered a hippie fad, "green" homes are moving mainstream. No wonder: Going green can cut home operating expenses by 30 to 70 percent. With the price of energy spiralling, green suddenly sounds better.

As welcome as the savings are, though, there's another important reason to think green when remodelling or buying a new home: your health. Green homes create a healthier interior habitat and are kinder on both the environment and your pocketbook.

Consumer demand is a driving factor in the greening wave, and the baby boomers are leading the way, according to the National Association of Home Builders (NAHB). As they seek vacation homes and move into 55-plus active-adult communities, baby boomers consider a high-performance home the best investment in the future, according to builder Don Ferrier, president of Ferrier Builders Inc. of Fort Worth, Texas, a leader in energy-efficient construction.

Ray Tonjes, chairman of the NAHB's Green Building Subcommittee, agrees.

"Today's consumer or buyer is far more knowledgeable and astute about building practices in general and more conscious about our environment and energy usage," says Tonjes, who has been building green for 20 years in Austin, Texas.

In 1990, Austin was the only city with a green-builder programme. Today more than 40 local and regional programmes are active. The NAHB Research Center estimates that close to 20,000 homes a year now are built using local green-building guidelines.

The growing demand has spurred action to develop national standards for building green homes, but the greening trend isn't restricted to new homes. In older homes, consumers increasingly are seeking ways to improve their environments in small steps or in major remodeling projects.

With ever-increasing new products on the market — from wall paints to flooring, decking, appliances and heating-cooling systems — going green no longer is the costly, difficult endeavor it once was.

"Green building is not about doing without or making do with less," says Jason McLennan, chief executive officer of the Cascadia Region Green Building Council in Seattle. It provides a better product and better value for your money in a way that conserves energy and resources, McLennan says.

In essence, green building seeks a balance between nature and man, creating habitats that are efficient, durable, comfortable and healthy. The terms "green building" and "sustainable development" came on the scene in the 1970s, first in residential construction. But the movement took off faster in the commercial segment, as major companies scored dramatic savings in energy and maintenance costs while also making a friendlier work habitat.

For years, building green was pitched more as a way of saving the environment. Then a heightened awareness about possible effects of mold and toxins from building materials made families think about the impact of their home interiors on their lives. Energy efficiency and indoor air quality now are the most important elements of residential green building, according to an NAHB survey.

"If we have a 'sick' home, what are we really providing for our kids?" asks McLennan.

While green building doesn't make everything perfect, McLennan says, it has been shown to greatly improve air quality and other environmental elements, such as humidity, glare and eye strain.

A key element to a healthier home is your heating-cooling system, advocates agree. The system should be efficient, sized properly for your home and installed and working correctly, says Richard Morgan, programme manager for the Austin Energy Green Building Programme. Austin Energy is the city-owned utility, and its programme long has been a green-building leader in working with builders, suppliers and homeowners. The city has its own star rating system for homes, and more than 50 percent of new homes in the area are built to green codes.

Many air systems are overdesigned with too much conditioning, particularly in humid regions, says John Knott, president of The Noisette Co. in North Charleston, S.C. Knott is a leader in both residential and commercial green developments worldwide, and his company currently is directing a major restoration programme that will turn a 3,000-acre area of North Charleston into a sustainable community of homes, businesses and parks.

"There's a big problem in air-conditioning systems, a huge opportunity for mold," says Knott, noting the major concern that has arisen in many homes in recent years. "The air-conditioning comes on and cools the house really fast and then goes off. When that happens, it hasn't had enough time to remove the humidity, so you get high moisture levels."

He recommends having a Thermidistat, which controls both temperature and humidity, and a dehumidifier in your system. Lowering the humidity and circulating the air will drop the temperature, thus cooling the house without having to use the air-conditioner as much, and it will help control mildew and mold.

Crawl spaces beneath homes also contribute to the mold problem.

"In hot, humid climates, the crawl spaces have supersaturated air that's sitting under the house. The pressure of that air actually migrates moisture into the house," says Knott, who recommends sealing, insulating and conditioning crawl spaces.

But while homes and offices need to be well-insulated and sealed to be energy efficient, they shouldn't be so "tight" that they're "sick" buildings, cautions Knott. Fresh-air ventilation is important. The newest, most advanced home heating-cooling systems now are health-oriented, purifying and conditioning the air and killing mold and mildew.

Knott says it doesn't take a huge outlay all at once for the average homeowner to start turning an existing house into a green one.

"Focus on simple things that get you the biggest bang for the buck initially," he says.

Two simple actions:

¦ Replace incandescent light bulbs with compact fluorescent bulbs. These cost more but last five to 10 times longer and consume up to 75 percent less energy. There's more variety in new fluorescents.

"If you don't have the money to do all at once, replace one bulb at a time, and in a year, you will have all changed. You will save a ton of money," McLennan says.

¦ Change showerheads and sink faucets to low-flow fixtures, a relatively inexpensive, easy task that can cut water bills.

Here are other actions you can take to make your home green:

¦ Have your home evaluated for energy efficiency. Carl Seville of SawHorse Inc., an award-winning renovation specialist in Atlanta, another city on the cutting edge of green building, says this is an important first step before deciding where to put your money.

The Home Energy Rating System, HERS, has certified raters who analyze homes and give recommendations on upgrading efficiency. One source of certified raters is the Residential Energy Services Network, www.resnet.us.

¦ Tackle toxicity. Get rid of products that emit gases, causing indoor air pollution that can lead to respiratory problems.

When a room, or the house, needs repainting, or when you replace carpet, floor finishes or furniture, scrutinise the contents of the products and choose ones that are nontoxic or have the lowest volatile organic compound (VOC) rating. When buying carpet, also check the backing and padding for toxicity.

¦ Check your exterior doors for air leakage and replace or put on storm doors.

¦ Inspect caulking, seals and insulation. If your windows are 25 to 30 years old, you likely can save money by replacing them, though new ones are costly.

New energy-efficient windows keep outdoor air from getting inside, thus cutting heating and cooling bills. Consider radiant barriers to reduce heat from the sun in hotter climates. Be sure all ductwork is sealed so there's no leakage of conditioned air. Insulation should have a rating geared to the climate, and if you're using fiberglass, be sure it's encapsulated, or sealed, so the fibers don't get into the air.

¦ As appliances need replacing, buy energy-efficient, low-flow ones. Look for Energy Star products that meet governmental efficiency standards. Front-load washing machines, more efficient and gentler on laundry than the top-load ones, are back on the market.

¦ If house siding needs replacing, consider Hardiplank, an acclaimed wood fiber-cement product that is extremely durable, can be sawed like lumber and comes with a 50-year warranty.