The trim completes the look,” says Brad Pompilli of Tri-State Home Improvement in Branford, Conn., referring to the accessories he uses with foam-backed vinyl siding. For Pompilli, upscale vinyl products — namely Crane Siding's CraneBoard and Royal Building Products' DuraPlank — have been a popular upsell along the coast of Long Island Sound where traditional Colonial and Greek Revival architecture set the tone. It's not a market that tolerates covering up the woodwork and slapping on narrow corner posts.
Foam Advantages Foam-backed vinyl has made strong inroads in high-end markets in recent years. The material consists of rigid vinyl panels glued over foam inserts. The adhesive is fairly gummy and stays flexible, but provides enough tack to bond the pieces together and improve the tensile strength of the unit. Most foam-backed products use expanded polystyrene foam inserts that have a coefficient of expansion that's nearly identical to the vinyl, so the dissimilar materials move as one.
Although the foam backing provides a modest boost in wall R-value and reduces sound transmission, the key selling point is appearance, Pompilli says. “It lays nice and flat on the wall, and the backing keeps the seams from opening up.”
Trim Details The foam increases the depth of the panels, so the job requires slightly different accessories. A special starter strip with an extended leg is needed to accommodate the added panel thickness. Some ordinary accessories, such as corner posts and J-channel, can be used but require foam shims. A variety of inserts and different thickness foam shims are readily available from distributors.
The added depth works well with modern flanged windows, but can present a challenge with existing ¾-inch casing. Bringing the deep J-channel to the edge means the existing trim will be recessed — a look that doesn't always fly in an upscale market.
For Pompilli, this isn't always a big concern. Many of the homeowners are willing to pay to strip the wall clean and install 3½- or 5-inch–wide window lineals. These come complete with sloped sills and crown molding across the head. “Crane offers a pretty complete system that's easy to install,” Pompilli says. “Of course, these accessories add to the price of the job [compared to coil stock], but most customers at this level are willing to pay more for a maintenance-free exterior with a historic look.”