Rigid PVC Residential Siding Using Specialty Minerals PCCs and Talc

The ready availability of wood in North America has driven the concept of the stick built house. In this method, a wood frame built piece by piece is covered in wood sheathing, and then a roof and siding are applied. Typical siding materials are wood, aluminum, steel, and PVC (vinyl). Because of its utility, low maintenance, and competitive installed pricing, vinyl siding has been a runaway favorite for more than a decade.

Specialty Minerals Precipitated Calcium Carbonate in PVC Siding
Polyvinyl chloride house siding has dramatically, changed the face of house building. This is a demanding application for PVC because of the high level of product performance required to displace more traditional materials such as wood, brick, stucco, and stone. PVC offers a colorful, lightweight, maintenance, free, cost-effective alternative to traditional materials. Delivery of these benefits requires careful attention to formulation and processing issues. Precipitated calcium carbonate (PCC) from Specialty Minerals Inc. (SMI) affords superior impact resistance, dimensional stability, and surface appearance. Whatever specific balance of properties you are searching for in PVC, there is a SMI PCC to help you reach your goals. See our product selector chart to make your choice or, for a customized recommendation, contact us with the details of your specific application.


Click on a product name to download the data sheet for the product or on a property to download the SMI brochure “Fillers in PVC – A Review of the Basics”. Click here to download a brochure on Tuffgard® PCC in rigid PVC.

Impact strength is a key requirement in house siding, but compounders cannot lose sight of formulation costs in meeting these impact requirements. SMI’s Tuffgard® and Ultra-Pflex® PCCs give formulators the added edge they need to balance cost and impact strength, while our Super-Pflex® PCCs impart balanced properties at lower cost through higher resin extension. Reduction or elimination of rubber-based impact modifiers is possible when using Tuffgard® and Ultra-Pflex® PCCs.

Long-term profile dimensional stability is another requirement in house siding where exposure to sunlight raises part temperatures to critical levels. Built-in stresses from extrusion processing can promote dimensional instability where high heat levels are possible. Localized hot spots can lead to part warpage. The small particle size of Tuffgard®, Ultra-Pflex® and Calolfort®S PCCs promote melt homogeneity in profile compounds while reducing long-term dimensional changes. Ultra-Pflex® and Calolfort®S PCC have added benefits, imparting whiteness, high surface gloss, and smooth appearance to critical appearance-grade parts.

Download the SMI publication “The Effect of Calcium Carbonate Size and Loading Level On the Impact Performance of Rigid PVC Compounds Containing Varying Amounts Of Acrylic Impact Modifier” by clicking here or download the publication “Adding Value to PVC Formulations with Ester Lubricants and Fine Calcium Carbonate” by clicking here.

Talc for Higher Temperature Applications of PVC Siding

SMI talc products deliver higher flexural strength levels even as temperatures climb. This is important in darker-colored siding products, particularly in hot climates such as the U.S. Southwest. House siding markets continue to experience high growth levels and SMI’s broad product line of calcium carbonates and talcs will enable you to offer your customers the highest level of cost-competitive, high-quality products.

Click here to download the SMI paper “Increasing the Flexural Modulus of Rigid PVC at Elevated Temperatures” for more information and data on the use of talc in rigid PVC.