Eco-additions: remodeling for a healthier house. (House & Home).

You love your home, but it's not perfect. Maybe it needs a bathroom on he ground floor, a bigger kitchen or another bedroom. Of course, you could move to bigger digs. Or you could do what millions of Americans do every year: stay put and remodel. Indeed, renovation is the fastest-growing segment of the housing market, climbing at a five percent clip each year.

For house-proud environmentalists, remodeling is more than just an opportunity to go upscale. "With renovation, a house can have better air quality and use less energy and fewer resources," says Bob Moffitt of the American Lung Association's Health House.

As with any project, green renovators need to know what they want and what to be watchful for. Here are a handful of tips to get you started:

* Contract with a knowledgeable builder. Contractors who are members of eco-oriented trade groups are more likely to know the latest green strategies, technologies and materials. Noted groups include the Energy and Environmental Building Association (952-881-1098, www.eeba.org), Northwest EcoBuilding Guild (206-575-2222, www.ecobuilding.org), and Northeast Sustainable Energy Association (413-774-6051, www.nesea.org). If you can't find a green specialist, ask potential contractors if they'd be willing to try an Earth-friendly approach. Suggest that they review a short primer, such as John and Lynn Marie Bower's The Healthy House Answer Book, or the video Your House, Your Heart, both available from the Healthy House Institute. If your renovations require lead paint or asbestos removal, make sure a certified specialist does the work. For names of lead abatement professionals, contact the federal Lead Listing (888-532-3547, www.leadlisting.org); for asbestos, contact your state and local health departments.

* Protect yourself. Remodeling will generate dust and particles and may release contaminants that had been lurking behind and around wails, ceilings and pipes. Keep them out of your living area by sealing off and limiting traffic into the construction zone. Even then, it's a good idea to vacuum after every workday and dust with a microfiber cloth. If renovations are extensive, consider moving out during the process, particularly if you have small kids (who are keenly sensitive to the effects of environmental contaminants).

* Careful with cabinets. Most bathroom and kitchen cabinets are fashioned from particle- or fiberboard, which off-gas formaldehyde from the glues. Cabinets made from exterior-grade plywood or solid wood emit little or none of the gas, though they are more expensive. Consider the chemical-free, healthy cabinetry of Neil Kelly Cabinets, (503-335-9275, www.neilkelly.com) or Kitchens & Baths by Don Johnson (773-548-2436, www.greencabinets.com). A cheaper option is to coat particle-board with a waterbased polyurethane sealer, which locks in formaldehyde.

* Paint it green. Regular paint harbors volatile organic compounds (VOCs), like benzene and acetone, which have been linked to respiratory ailments and the destruction of the ozone layer. Look for low- or zero-VOC paints like Healthspec by Sherwin Williams or Safecoat by AFM Enterprises. For a list of paints that have earned the "green seal" of approval from the Green Seal company, see www.doi.gov/oepc/re ports/cgr_paints.pdf.

* Control the moisture. High moisture can spawn allergenic molds, mildew and dust mites. Prevent excess moisture with watertight roofing materials and gutter systems. Outfit bathrooms and kitchens with fans and range hoods.

* Green building materials. Wood certified by the Forest Stewardship Council comes from forests managed according to social and environmental criteria. You can also choose from a host of alternative materials, such as cork or tile flooring (instead of vinyl), or wool and cotton carpet (versus synthetic).

* Tighten up. Before you close up renovated interiors, insulate against the elements. Fill the gaps between joists in ceilings and studs in walls with batting; blow loose-fill into hard-to-reach attic spaces. Seal potential air leaks along cracks. Insulated glass windows with low-emissivity coating--sometimes called "super windows"--can cut heat loss by 25 percent compared to standard windows. For more strategies, see No Regrets Remodeling by the editors of Home Energy magazine. Because buttoning up your home too much may keep bad air from escaping and good air from entering, consider installing a ventilation system.

* Watch the watts. Generally, newer appliances tug more lightly on the plug than earlier models do. Look for products with the Energy Star logo, which indicates they've met the government's stricter energy standards.

CONTACT: Healthy House Institute, [phone], www.hhinst.com.

MARK HARRIS is a Pennsylvania-based freelance writer.