With the aging of the Baby Boomer generation, more homes are coming available in older, established neighborhoods. Buying to remodel is increasingly common. The new homeowners want the big lots and beautiful shade trees close to schools and other community amenities. They don't want the 1960s era Formica or the 1970s shag carpet. Many of these homes have not been updated in years. The trend now is to opt not just for upgrades, but for environmentally friendly, energy efficient upgrades. What are the most cost-effective ways to go green during a remodel?

** Good Shade Trees are Great Energy Savers **

One of the greatest advantages older lots offer are those beautiful shade trees, which save on heating and cooling costs by as much as 30 percent over unshaded roofs. Trees on the south and west side of buildings are most effective, but a heat load can also be dramatically reduced by shade on patios, sidewalks, and driveways. If you are adding trees or contemplating removing any, keep these considerations in mind.

** Always Consider Insulation and Caulking **

Having insulation blown into your attic before you move in is an excellent and affordable "green" upgrade. In older homes existing insulation tends to run 25-50% less than current energy codes suggest. With 8-10 inches of insulation homeowners can, on average, save $145 a year on heating and cooling costs, but this differs widely by climate. In hotter regions like Texas and the American Southwest, these savings will be exponentially higher. Heating and cooling expenses account for about 70% of the cost of "running" a home and create the majority of emissions coming from the structure. Any savings are to your advantage, as multiple measures add up quickly in terms of dollars and cents, and carry year-round benefits.

This idea of stopping air leaks and increasing the efficiency of the home's heating and cooling systems can be expanded to include relatively minor projects that are most often considered "cosmetic." Replacing the front door? Make sure you also replace the weather stripping and re-caulk the frame. Updating the windows? Go for double-pane glass. Energy Star qualified doors, windows, and skylights can reduce energy bills by 15%.

** Add Natural Light Where Possible **

An excellent way to lower electric bills is to use sunlight whenever possible. Products like the Solatube can be installed on the roof to channel sunlight into any room without increasing the temperature of that room. The units consist of a light-gathering "bulb" that sits on the roof and a tube that angles the light into the room. Installation time is approximately two hours and the leak-proof design will work with any room type.

This same effect can be achieved to a degree by adding transoms over doors or simply enlarging the size of existing windows. Remember, however, you want to add light, not heat. It's important to look at heat-blocking window treatments, both chemical and physical (for instance, some double windows have electric shades built in), tints, and other methods to decrease the heat load coming into the house.

** Think About Potential Toxicity When Replacing Carpet **

In choosing carpeting, the major consideration is how many volatile organic compounds there are in the fiber and in the adhesives used during installation. This not only improves indoor air quality, a major consideration for people with chemical sensitivities and allergies, but lessens the amount of toxic gas that can be released in the event of a fire. In the cases of residential fires, occupants are generally overcome by smoke and fumes, not killed by the flames.

** The List of Potential Green Upgrades is Endless **

From solar water heaters to programmable thermostats to simple ceiling fans, the ways to make your home more energy efficient and "green" are almost endless. Exciting products come on the market daily and consequently, prices have dropped dramatically. Do not, however, expect most contractors to be aware of this availability. "That's too expensive" may well be code for "I don't know what you're talking about."

Do your research and go into any interview with a contractor armed with a list of questions and suggestions. If you're working with a contractor who is taking a more traditional approach to the remodel, interview another contractor. Any remodel can be made "greener" and can achieve higher levels of energy efficiency in any home by including a number of well-chosen, but relatively minor changes. Remodeling in the 21st century is not just about knocking out the dining room wall. It's about knocking our your preconceptions and those of your contractor about what is not only possible, but practical.