Sweeter than Cedar
For more than 200 years, vertical-grain Western red cedar—today in short supply—was the siding of choice for the New England-style home. While materials ranging from vinyl siding to planks made from fiber cement have been substituted, it simply has not been possible to accurately re-create the look of the true New England home due to various characteristics of these materials.
But a new siding product that uses a novel heat-reflecting coating material could change that. The product, result of a collaborative effort involving The Sherwin-Williams Co. (Cleveland, OH) and NuCedar Mills (Chicopee, MA), in conjunction with Jain Irrigation Systems Ltd. (Jalgaon, India), is based on clapboard siding milled from solid boards of cellular PVC, a material that already has been embraced by builders and architects for trim, rake, cornerboard and molding.
The fully-recyclable, specially formulated cellular PVC sheet is manufactured in India by Jain using partially recycled content. A new paint formulation provided by Sherwin-Williams enables NuCedar to paint the sheet with a highly-durable, heat-repelling coating that allows application of mid-tones and deep, saturated colors to vinyl.
For the vinyl siding industry, the trend toward darker colors posed a challenge. Dark colors absorb solar heat—often enough to cause significant expansion of plastics—and the result was a tendency to warp and bow when coated with darker colors.
Sherwin-Williams’ Polane solar reflective polyurethane enamel alleviates heat absorption problems, creating a heat-repelling finish that enables vinyl siding, shutters, windows, trim and patio doors to be coated with dark colors without the heat build-up that contributes to expansion. According to the company, the HAP-free, low-VOC polyurethane enamel resists fading and provides an unusually strong bond to the substrate. It meets or exceeds the ASTM D 3679-05 standard for vinyl siding. NuCedar applies the material to its CedarGrain Classic Clapboard product in 22 standard and 1,400 custom colors that match Sherwin-Williams’ Duration paint line.
Production starts when PVC sheet shipped by container from India to NuCedar is ripped into boards and passed through a molder to produce its proprietary tongue-and-groove design. The boards are then split to mimic real Western red cedar and hole-punched.
NuCedar had years of experience in the market for similar building materials, but in-house finishing was new to them. Managers understood the need to develop a highly automated production process to keep costs as low as possible in the competitive market for residential and commercial building materials.
They worked with Sherwin-Williams to develop a finishing process that starts in a high-tech paint kitchen, where 12 colors of paint are kept under pressure and hard-wired to a manifold to allow fast, computerized color changes. The system allows independent control of the pressure and atomization of the finishing line’s HVLP spray guns. Plural component spray equipment enables mixing at the gun so there are no pot life concerns, and the lines can be quickly purged to change out colors.
Finished siding is stacked face-to-face without slip sheets because the durable coating doesn’t scratch in transport. Once on the job, the boards can be quickly installed with no special tools. According to NuCedar Mills, the system has been wind-tested to 225 mph using aluminum or stainless steel nails with no damage.
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