Classic Shake Siding — National Gypsum Co.

Product Description

Classic Shake Siding was a fiber-cement building panel manufactured by National Gypsum Company and produced from approximately 1958 through 1981. Designed to replicate the aesthetic appearance of traditional wood shake siding, the product offered a textured, dimensional surface that appealed to residential and commercial builders seeking a low-maintenance alternative to natural wood. The panels were engineered to resist moisture, fire, and weathering — properties that made them an attractive choice for exterior cladding applications throughout much of the postwar construction boom.

National Gypsum Company was a major industrial building materials manufacturer headquartered in Dallas, Texas, with operations spanning gypsum wallboard, ceiling tile, and exterior cladding products. The company supplied materials to construction markets across the United States for much of the twentieth century. Classic Shake Siding represented one component of the company’s broader exterior products line during the period when asbestos-reinforced building materials were standard throughout the industry.

The siding panels were marketed to contractors, homebuilders, and distributors as a durable, finished exterior surface. Because the product was sold into both new construction and renovation markets, it was installed across a wide geographic range and in structures that may still be standing today. Buildings constructed or renovated during the product’s production window — 1958 to 1981 — may contain Classic Shake Siding and should be evaluated by a qualified asbestos inspector before any renovation, repair, or demolition work begins.

Asbestos Content

Classic Shake Siding contained chrysotile asbestos, the most commercially prevalent form of asbestos used in building materials throughout the twentieth century. Chrysotile, sometimes referred to as white asbestos, is a serpentine mineral fiber that was incorporated into fiber-cement and composite building products to improve tensile strength, dimensional stability, and resistance to cracking. In siding panels such as Classic Shake Siding, chrysotile fibers were integrated into the cementitious matrix during the manufacturing process, binding with the other materials to form a rigid, weather-resistant composite panel.

Although chrysotile has sometimes been characterized as less hazardous than amphibole asbestos varieties, regulatory bodies including the Environmental Protection Agency (EPA) and the Occupational Safety and Health Administration (OSHA) recognize chrysotile as a human carcinogen with no established safe level of exposure. The EPA’s Asbestos Hazard Emergency Response Act (AHERA) framework and OSHA’s asbestos standards apply to chrysotile-containing materials and govern how such materials must be assessed, managed, and remediated in buildings and workplaces.

When Classic Shake Siding panels remain intact and undisturbed, the chrysotile fibers are generally bound within the cement matrix and are considered non-friable under standard conditions. However, cutting, sawing, drilling, sanding, breaking, or removing panels — activities common during installation, renovation, repair, and demolition — can fracture the matrix and release respirable asbestos fibers into the air. Once airborne, chrysotile fibers can be inhaled and may become permanently embedded in lung tissue, where they are associated with serious and potentially fatal diseases including mesothelioma, asbestosis, and lung cancer.

How Workers Were Exposed

Industrial workers and construction tradespeople were the primary population at risk of occupational asbestos exposure from Classic Shake Siding during its period of manufacture and use. Exposure occurred at multiple points in the product’s lifecycle, from manufacturing through installation, maintenance, and eventual removal.

At National Gypsum’s manufacturing facilities, workers involved in mixing, molding, pressing, and finishing the siding panels would have encountered raw chrysotile fibers and asbestos-laden dust as a routine part of their work environment. Industrial workers operating in those facilities were present in environments where airborne fiber concentrations could reach significant levels, particularly before dust control measures and engineering controls were consistently implemented across the industry.

In the field, workers involved in the handling and installation of Classic Shake Siding were exposed when cutting panels to fit dimensions of a specific structure. Cutting panels with power saws, circular saws, or hand tools generated fine airborne particulate that included respirable asbestos fibers. Drilling holes for fasteners and scoring panels for trimming produced similar conditions. Workers in confined spaces or areas with limited ventilation faced heightened exposure potential.

Renovation and demolition workers faced particular risk when removing Classic Shake Siding from older structures, as aging panels were more prone to cracking and fracturing during handling. Maintenance workers who repaired damaged sections of exterior siding without proper respiratory protection and containment procedures were similarly at risk. In many cases during the product’s operational years, workers were not provided with adequate protective equipment and were not informed of the asbestos content of the materials they were handling.

Litigation records document that workers exposed to asbestos-containing products manufactured by National Gypsum and similar companies developed serious diseases, including malignant mesothelioma, asbestosis, and other asbestos-related conditions, years or decades after their initial exposures. Plaintiffs alleged that National Gypsum and other manufacturers were aware of the hazards associated with asbestos-containing building products but failed to adequately warn workers or take timely steps to eliminate asbestos from their product lines.

Documented Trust Fund / Legal Options

Classic Shake Siding is classified as a Tier 2 — Litigated product. There is no currently active asbestos bankruptcy trust fund established specifically for claims arising from National Gypsum’s Classic Shake Siding or its other asbestos-containing products that would provide a straightforward trust claim process. Individuals seeking compensation for asbestos-related diseases connected to this product must pursue their claims through the civil litigation system.

Litigation records document that plaintiffs diagnosed with mesothelioma, lung cancer, and asbestosis have filed claims in connection with asbestos-containing building materials manufactured by National Gypsum Company. Plaintiffs alleged that exposure to asbestos fibers during the manufacture, installation, maintenance, and removal of products including Classic Shake Siding was a substantial contributing cause of their asbestos-related diseases. Cases have been filed in state and federal courts across the United States by workers and their surviving family members.

Individuals who were employed as industrial workers at National Gypsum manufacturing facilities, or who worked as contractors, builders, or tradespeople handling Classic Shake Siding during its production years of 1958 through 1981, and who have subsequently been diagnosed with mesothelioma, asbestosis, lung cancer, or another asbestos-related disease, may have grounds for a civil claim.

Because asbestos-related diseases typically have latency periods spanning decades, diagnoses continue to occur among workers whose exposures took place during the mid-to-late twentieth century. Those affected, or the families of workers who have died from asbestos-related disease, are encouraged to consult with a qualified asbestos litigation attorney to evaluate the specific facts of their exposure history and medical diagnosis. An experienced attorney can assess whether viable claims exist, identify all potential defendants and sources of compensation, and advise on applicable statutes of limitations, which vary by state and by disease type.

This article is provided for informational and reference purposes only. It does not constitute legal advice. Individuals with potential asbestos-related claims should consult a licensed attorney.