Foam-backed vinyl must be used with compatible trim stock, and most manufacturers offer a complete line of accessories.
Courtesy Crane Performance Siding Foam-backed vinyl must be used with compatible trim stock, and most manufacturers offer a complete line of accessories.

Vinyl, America's most popular siding material, continues to gain ground against costlier, higher-maintenance claddings. Originally a budget and mid-market alternative, today's premium options offer promise for the upscale replacement market. Good examples include foam-backed vinyl siding such as Crane Performance Siding's CraneBoard, CertainTeed's CedarBoards, and Alside's Charter Oak Energy Elite.

The new products are a two-part sandwich — standard vinyl laminated to a stiffening layer of profiled insulating foam. Most brands use expanded polystyrene (EPS) foam (the familiar “bead-board”) for the foam backer, but not all: Alcoa's Structure brand is backed with Dow Styrofoam extruded polypropylene (XPP). Not all brands use solid foam, either — Royal Building Products' DuraPlank has a corrugated, channeled backer profile.

Either way, the foam backing helps overcome the appearance characteristics that flag vinyl as a synthetic material. The sturdy sandwich spans small irregularities in the underlying wall and takes out the telltale twists that say “plastic” — even in wider widths and longer lengths.

But it's not all about looks: The new products also offer performance advantages. The insulating foam lets most manufacturers claim an energy advantage — typically adding around R-3 or R-4 to a wall's total R-value. Crane claims that its product's interlocking joints provide a tight enough seal to stop wind penetration from stealing away the material's insulating benefit.

Then there's toughness. Regular vinyl is subject to puncture damage from small flying objects like hail or an errant golf ball, but foam-backed brands get a 300% improvement in impact resistance. It's not a hurricane defense, but it boosts the wall's odds of withstanding a stone kicked out by a lawn mower.

Brad Pompilli runs Tri-State Home Improvement in Branford, Conn. Pompilli's crews install foam-backed siding from both Crane and Royal Building Products, and he says that the upgrade sells well in his market. “The labor is about the same,” Pompilli notes, “but you do pay a little more for the product, and, of course, you charge for that. But we aren't trying to be the low bidder on a job,” he says. “Once customers see the difference, they don't want anything else.”

Appearance is the key selling point, Pompilli says. “It lays nice and flat on the wall and the backing also keeps the seams from opening up, if you have seams.” By using 25-foot lengths, he says, many walls have no seams showing. “With the right accessories — the corner pieces and the J-channel trim — it looks very close to wood. You pull up on the street and it looks like a new house with wood siding and a fresh coat of paint.”