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The Evolution of Vinyl Siding

Homeowners can be an obsessive bunch. They think it's good sport to drive around new, upscale subdivisions and study siding. It's fun to see how that Victorian reproduction has mixed natural-colored, hand-split shakes with ivy green, half-round shingles. That Colonial looks striking, with its crisp, gray clapboards, trimmed out with white crown window molding and corner blocks flanking the doors. But look closely. The biggest surprise might be that most of these handsome facades are created not from wood, but from vinyl. There was a time when vinyl-clad houses were easy to spot.
Courtesy Crane Performance Siding
Expansion and contraction produced wavy walls and obvious laps or spaces where panels meet. Years of sun caused fading and discoloration. Manufacturers appear to have taken these shortcomings to heart. Forty years of gradual improvements has produced a new generation of vinyl siding that is extremely durable and fade resistant. Technology has led to the creation of new profiles and finishes that really mimic wood, such as textured cedar.
Increasingly, this wood wannabe is looking like the real thing. Five years ago, the trade group representing major manufacturers began promoting a certification program based on a standard developed by the American Society for Testing & Materials. This program, which includes independent inspectors, addresses long-standing concerns about vinyl, including impact resistance, color fading and wind damage. "This gives people confidence in the product," says Jery Huntley, executive director of the Vinyl Siding Institute in Washington. Vinyl siding is most popular in the Northeast and Midwest, Huntley says, where many manufacturers got their starts. But it's also growing now in the South. Woodworkers and other purists may scoff at vinyl's pretences. And vinyl siding won't be appropriate for replacing wood in all cases.
But it's hard to ignore the growing degree of consumer acceptance. Since 1995, vinyl has become the dominant residential siding material, surpassing wood, hardboard, aluminum and fiber cement. Vinyl now accounts for nearly a third of the cladding used in new construction, according to CertainTeed Corp., one of the nation's largest vinyl manufacturers, and 95 percent of remodeling jobs. Vinyl's rise in popularity has been anticipated for some time. A 1994 study of residential siding done by George Carter & Affiliates, of Hillsdale, N.J., looked at trends dating back to 1985 and projected preference changes to 2004. Through the early 1990s, it found growth in vinyl siding and steep declines in aluminum and steel. Wood siding, including hardboard, cedar and plywood, also declined.
In 2002, George Carter & Affiliates did more market research on residential siding. They surveyed builders and remodelers, asking several purchase-decision- and performance-related questions, with a focus on vinyl and fiber cement. The topics included durability, purchase price, damage and low maintenance. Vinyl got top marks. One of the few negatives dealt with purchase price, indicating a perception that prices had risen without a commensurate increase in value. Fiber cement, for its part, registered concerns for price and ease of installation, although the study suggested those shortcomings could be corrected with education and promotion. For now, though, vinyl is the leader. Accounting for vinyl's growth is low maintenance and low cost over the life of the product. A 1996 study cited by the VSI looked at cost and maintenance of siding options over a 20-year period. It found the cost of vinyl siding to be 51 percent of cedar-textured plywood, 64 percent of aluminum and 37 percent of brick. So if you live in a home that needs re-siding, or you are considering new construction, vinyl is worth exploring.
This isn't to say that vinyl siding is foolproof, or bulletproof, for that matter. As with any building material, it must be installed properly. And while it can be called low maintenance because it doesn't rot and doesn't need painting, there are still a few things you need to do to keep it looking its best. The search for long-lasting home siding that doesn't need a lot of upkeep probably started soon after people stopped living in caves. In a nation covered with forests, wood emerged as the logical first choice for settlers in the United States. Wood remains popular in New England and some other markets, despite the cost of painting and maintenance to prevent rot. But by the 20th century, the search for a less demanding siding was in full swing. Mastic, which is now part of Alcoa Home Exteriors, takes credit for developing the first low-maintenance siding, an asphalt-based product called Insulbric, which emerged in the 1930s. Asbestos came on the scene soon after, prized as a material that wouldn't burn and wasn't bothered by termites. But asbestos siding absorbed moisture and faded easily, and its fibers are linked to health problems.
Aluminum created a revolution in the 1940s. Lightweight, rustproof and easy to apply, it was popular with remodelers and homeowners. But aluminum dents easily and its baked-on, painted surface can chalk and stain. Other alternatives have competed for popularity with some success. They include hardboard, which is a mix of wood chips and epoxy resin, and fiber cement, which is made from cement and clay and has been used for years in Europe. Vinyl came on the market in the late 1950s.
Vinyl has become a generic term for material made from polyvinyl chloride, or PVC, resin. This resin starts as a powder and is a thermoplastic, which means it can be extruded, shaped and embossed under high heat. While PVC is the principle ingredient in vinyl siding, other compounds are added to create color, texture, impact resistance and other properties. The resin is heated to more than 300°, pushed through a die and embossed with finishes that range from smooth to wood grain. Recently, companies have been using polypropylene to make shingles, which are injection molded to create the hand-split look of cedar shakes. Manufacturers check their production runs for dozens of quality standards, including panel width, weight, bow (straightness of panels) and embossing.
At least twice a year, independent inspectors contracted by the VSI visit plants as part of the voluntary certification program. Long-term weathering tests are also conducted in various climates to check for fade resistance. Homeowners can check whether the siding that will be used on their projects has passed the certification tests by looking for the VSI Certified logo on the box. According to VSI, the certification means the product meets all advertised specifications for color, thickness, length, width and other measurements. It will also meet impact-resistance standards, lie straight on a wall, not buckle under normal use and stay put in heavy winds. Homeowners can learn more about the certification program at the VSI's website: While vinyl siding is available for do-it-yourselfers from retail home-improvement stores, it's a job that's mostly left to professionals.
Roughly 95 percent of vinyl siding is installed by contractors, according to the industry. Still, it may be worthwhile to become familiar with some of the key design features of vinyl siding and its installation. The information will provide a better sense of why some jobs come out better than others. And it could make you a more educated shopper if you're looking to hire a contractor. Most horizontal siding is hung from a nail flange or hem that runs along the top of each panel, which are typically 12 feet long. Nails or staples can be used to secure the panel, but because temperature changes can make vinyl siding expand and contract a half-inch over a typical panel length, contractors typically leave at least a 1/32-inch space between the nail head and the vinyl. Otherwise, the panel can buckle. A new approach, used by the Wolverine division of CertainTeed, has a flexible nail hem in which the panel hangs from thousands of fusion-welded cables that form a sort of fabric. This system allows for tight nailing and lets the panel float over minor imperfections in the wall and adjust to temperature changes, according to CertainTeed.
It also makes the panels highly wind resistant. The Millennium brand - featuring the SmartWall technology system - being promoted by Wolverine and CertainTeed claims a wind-load rating of 270 mph. "The house will blow off its foundation", says Walter Hoyt of CertainTeed Corp. in Valley Forge, Pa. "But while it's going over Kansas, it's looking good."

Vinyl siding is also designed to keep out the weather. But contrary to first impressions, a vinyl-clad wall isn't really waterproof. In fact, dealing with water seems to be one of the more challenging aspects of vinyl siding installation. "Vinyl siding is not designed by itself to be a watertight barrier," Hoyt says. Panels join together at the buttlock, the bottom edge of the panel opposite the nail hem.
Look for weep holes in the butt, which allow any incidental moisture or water vapor to escape. At the same time, Hoyt says, it's important to keep rain from getting behind the siding. That means flashing must be correctly installed at windows, doors and gables. To address moisture retention that can lead to mold or rot, homes should be swaddled in a breathable house wrap. In re-siding, though, contractors also tend to use insulation board to provide a flat, level surface and make older homes more thermally efficient. "The underlayment is key," says Bob Shindler, vice president for marketing at Alside Inc., in Cuyahoga Falls, Ohio. "It either acts as a vapor barrier or promotes breathability." Check with your contractor to see what he or she will use for an underlayment.
There are increasingly more options out there. Pactiv Corp., for instance, markets an extruded polystyrene in its GreenGuard product line that has low moisture absorption and is perforated to allow vapor to pass. An interesting product from Progressive Foam Technologies, called Fullback, is a patented, contoured foam-support and insulating system that fits the profile of the siding placed over it. It has low water permeability, is breathable and has an insulating R-value of between 2.8 and 3.3, depending on the profile, according to the National Association of Home Builders Research Center ( An overall primer on how to install siding is available from the VSI. It's a free, 40-page guide called Vinyl Siding Installation: A How-To Guide. Call the Vinyl Siding Information Center at 888-FOR-VSI-1, or check CertainTeed also has a comprehensive guide, geared toward contractors in its Master Craftsman Education & Development Program.
It's available by calling 800-233-8990. Because vinyl siding has to be installed correctly to perform as designed, you'll want to spend some time finding the right contractor. There's no magic answer here. Just do your homework. If you admire homes in your neighborhood that have vinyl siding, ask the owners who did the work and if they are happy with the outcome. Ask to take an up-close look at their homes to study the workmanship yourself. Contact the contractor and ask for a few references. A call to the local Better Business Bureau or your state's consumer protection agency may be worthwhile, to make sure the contractor has a good track record. Some manufacturers will also refer qualified installers. Wolverine maintains a toll-free number for referrals to its Master Craftsman network through area distributors, 800-823-1488. The information can also be found at
Even properly installed vinyl siding won't look perfect forever if it's abused or completely ignored. For instance, vinyl can distort at temperatures above 160° F. Those temperatures can occur in warm climates from reflected or radiated heat sources, such as paved driveways. Screens, awnings and landscaping can reduce these problems on severe exposures. And, of course, keep your barbecue grill well away from the house. If a panel does become damaged, it can be replaced. The locking system that connects each panel to the other can be undone with an unlocking or ziplock tool. Vinyl also gets dirty from pollution, bird droppings and weather, as does any siding. It can be washed with soapy water and a cloth or soft-bristle brush. Start at the bottom and work up, to avoid streaking.
Rinse before the soap dries. A power washer is okay, but hold it at eye level. Don't spray under the panels, where water can be forced into the weep holes and behind the siding. Stains, including oil, tar, crayon and pens, can be removed with a variety of cleaners. They include Fantastik and Murphy Oil Soap. Mildew or mold can be treated with a solution of 30 percent vinegar and 70 percent water. For a list of approved cleaners and techniques, check the VSI's Vinyl Siding Cleaning and Maintenance Guide at
Beyond the issues of installation and maintenance, the biggest concerns of most homeowners remains color and style. These days, it's easier to get a sense of how different colors and accessories will look on your house, thanks to the Internet. Many manufacturers have interactive areas on their websites to let you choose colors for siding, trim and shutters, for instance, then print it out. "One of the beautiful things about replacing siding," says Shindler at Alside, "is you can really transform the look of your home."

Maybe you can even fool the folks who drive around looking at siding. Tux Turkel is a freelance writer based in Portland, Maine.