Expecting to plant a "For Sale" sign in the front yard any time soon? Whether the target date for listing your home on the market is a few months or a few years away -- or whether you simply like to make decisions with an eye toward the future -- you may well be wondering how putting some money into the house now will pay off later.

The hottest trends in home improvement feature environmentally friendly living, recycled products, and high-tech innovation -- all in a warm and inviting space.

Judging by the number of television shows devoted to the subject, it seems like nearly everyone is interested in remodeling or renovating their home. In some ways, it's reasonable: Two-thirds of owner-occupied homes are at least 25 years old, research by the Harvard University's Joint Center for Housing Studies found -- and that means there are millions of homes in need of an update.

To find out what's popular -- and what's not -- in the world of home improvements, we talked to several architects and designers to find out what trends they were seeing in the home renovation market.

Everything old is new again
Old houses might need updates, but a bit of the space's original character can remain, says Robin Wilson, CEO of Robin Wilson Home. Antique doors, lighting, hardware and floors can be preserved and restored to their former glory, even while adding the latest technology and materials. It might be time to ditch the fake wood paneling in the rec room, but the wide-plank hardwood floors in the den can be refinished to give an old room new sheen.

Recycled products are also making their way into home renovations: Kitchen countertops can be made from recycled aluminum, glass and even paper. Kitchen and bathroom sinks are made from recycled aluminum and bronze. Even the stuff you don't see in a home renovation -- such as insulation -- can include a significant percentage of recycled materials.

While recycled products have been around for some time, there's been a surge in interest, says Eric Phillips, vice president and general manager at DreamMaker Bath and Kitchen in Apex, N.C. Prices have come down and aesthetics have improved. "You don't have to sacrifice form or function for these products," he says.

Green solutions
There's a growing interest in environmentally friendly renovations -- which makes both ecological and economic sense. "People understand that using green products and systems can make their home more energy efficient and improve indoor air quality," says Maureen Ness, a project architect at the Minneapolis architecture and interior design firm LHB. "It saves money and makes their house healthier."

Phillips notes that people are beginning to choose eucalyptus woods, a fast-growing tree with wood that can be used for flooring and countertops. Water-saving devices in washers and toilets and energy-saving products from lighting to Energy Star appliances are getting a boost as well.