Merle Henkenius, Popular Mechanics

Guide To Vinyl Siding

If you've been thinking of vinyl siding for your home, you've picked a good time. Vinyl quality has never been better and the range of design options is truly impressive.

Among these are new trim profiles that go a long way toward making vinyl look more like traditional wood siding, especially at the edges. The purist's lament has, of course, always been that vinyl simply looks too much like the plastic that it is. True enough, but with vinyl now claiming 50 percent of the market -- as much as all other exteriors combined -- perceptions are clearly changing.

There are good reasons for vinyl's growing popularity. Manufacturers have spent 30 years improving its appearance and durability, while we've crammed more and more activities and work into each week. Today, more than ever, we're inclined to focus on the gift of time that a low-maintenance product represents. And the more we see vinyl being installed, the more acceptable its peculiarities become. To a great many homeowners these days, vinyl is a reasonable response to modern times.

Now you can have your gingerbread, and eat it, too. Vinyl siding makers jump on the architectural-millwork bandwagon, producing traditional profiles and details that never need painting. From Country Victorian to upscale Colonial, the possibilities have never been more varied.

A Vinyl Siding Primer

Vinyl is made from a PVC (polyvinyl chloride) plastic resin that's heated until molten and then extruded into sheets. The sheets are then embossed with a brushed or wood-grain pattern that provides textural interest and dulls PVC's inherently shiny and synthetic-looking surface. While still hot, the sheets are formed into siding panel profiles.

Manufacturers use additives to improve impact resistance, and to prevent ultraviolet damage and color fading. Color pigments are mixed with the vinyl resin before the plastic is extruded, so vinyl color is full depth, or nearly so.

To cut waste and reduce costs, most makers have adopted a co-extrusion process that fuses one layer of vinyl over another. The bottom layer is a combination of new and scrap vinyl, while the top layer is virgin vinyl, containing the flexibility and weatherization additives. The top layer, called cap stock, is typically 30 to 35 percent of the total thickness.

The larger siding manufacturers now warrant their products to the original owner for 50 years or for life. Some warranties can be passed to a second owner, but they may become prorated at this point.