Few subjects in the whole arena of residential construction products draw battle lines as sharply as vinyl siding.
Proponents tout the fact that it never needs painting, while its detractors insist that houses should never be covered with anything but real wood.
As a building material, vinyl siding is relatively new — it was introduced in the late 1950s as a substitute for aluminum siding. But its reputation was tarnished in the early days when it cracked, faded, buckled, and sagged.
Ongoing changes in the product's chemistry and installation techniques have improved its performance and furthered its acceptance by builders and homeowners.
In fact, vinyl has captured 32 percent of the U.S. siding market for new homes, with no end in sight to its growing popularity. The reason, in part, is because it's often (but not always) cheaper than red cedar or redwood and takes less time to install.
A mid-grade vinyl costs about $1.60 per square foot to install, not including the necessary trim pieces, while the installed price of mid-grade cedar clapboard, exclusive of trim and paint, is about 2.5 times higher. (Some premium vinyls cost about the same as the best grade of cedar, but the installed cost is still lower because it goes up faster and doesn't need painting.)
For many people, price isn't the issue at all; the real seduction of plastic siding is reduced maintenance. That's exactly why a wood guy like This Old House general contractor Tom Silva put vinyl on his house 20 years ago.
"I don't have time for painting," he explains. "I'd rather spend weekends on my boat." Of course, with the right maintenance, wood will last indefinitely. Vinyl can't match that claim because no one knows for sure how long it will last.
All Plastic Siding is Not the Same
Vinyl is a polymer formed during a chemical do-si-do between ethylene gas and chlorine, which produces a fine white powder called vinyl resin. When it's melted and mixed with different additives, the resulting compound can be as rigid as pipe, as supple as a shower curtain, or durable enough to survive the heavy foot traffic on a kitchen floor.
New, so-called virgin vinyl siding has a greater complement of the key additives that impart flexibility and resistance to UV degradation. Some manufacturers will tout their product as 100 percent virgin (along with a mention of its supposed superiority), but most siding is made with a core of remelted vinyl top-coated with virgin material.
Typically, vinyl siding is extruded through a die, but to produce the deepest patterns and crispest edges, panels must be molded from polypropylene, a more expensive plastic. Molded panels are typically no more than 4 feet long, while vinyl extrusions can be virtually any length.
Rap on a vinyl-sided wall with your knuckles, and it will flex and sound hollow. That's because, in most cases, only a relatively small area of a vinyl panel is actually resting against the sheathing.