USG Durabond and Structo-Lite Joint Compound and Plaster Base

Product Description

USG Durabond and Structo-Lite were two distinct but related product lines manufactured by United States Gypsum Corporation (USG), one of the largest gypsum and drywall product manufacturers in the United States. Both products were widely used in residential, commercial, and industrial construction throughout the 1950s, 1960s, and into the mid-1970s.

Durabond was a setting-type joint compound formulated to harden through a chemical reaction rather than simple drying. This made it exceptionally durable and fast-setting, which suited applications requiring a strong, permanent bond—including filling deep voids, bedding corner bead, laminating gypsum panels, and finishing the first coats over taped drywall seams. Its quick-set chemistry made it a preferred choice for professional drywall finishers who needed to move through stages of finishing work rapidly.

Structo-Lite was a gypsum-based plaster basecoat, also manufactured by USG. It was designed as a lightweight aggregate plaster used in the scratch and brown coat stages of traditional three-coat plaster systems. Structo-Lite was commonly applied to gypsum lath, masonry, and other substrates as a preparatory layer before the final finish coat was applied. Its lightweight formulation—achieved in part through the inclusion of perlite or other aggregate materials—made it easier to apply and helped reduce the overall weight load on wall and ceiling structures.

Both products were sold under the United States Gypsum brand and distributed nationally through building supply dealers and contractor supply houses. They were standard materials across job sites from post-World War II construction booms through the early urban renewal and high-rise construction periods of the 1960s and 1970s.

Asbestos Content

Pre-1977 formulations of both USG Durabond and Structo-Lite contained chrysotile asbestos. Chrysotile, also known as white asbestos, is the most commercially prevalent form of asbestos and was incorporated into gypsum-based construction products for several practical reasons: it improved workability, added tensile reinforcement to the set compound or plaster, and helped resist cracking during the curing process.

Chrysotile asbestos was a recognized industrial ingredient in many USG products manufactured during this period. Its inclusion in Durabond formulations and Structo-Lite plaster basecoats was consistent with industry-wide practices at the time, when asbestos was broadly understood as a cost-effective performance additive rather than as a health hazard.

USG reformulated or removed asbestos from its product lines in response to evolving regulatory pressure and growing scientific consensus about asbestos-related disease. The U.S. Environmental Protection Agency’s Asbestos Hazard Emergency Response Act (AHERA) and OSHA’s airborne fiber standards established legal frameworks that effectively drove asbestos out of most construction materials by the late 1970s. However, products manufactured and installed before 1977 remain present in older buildings across the country and continue to pose exposure risks during renovation, repair, and demolition work.

How Workers Were Exposed

Workers who applied, sanded, or disturbed USG Durabond and Structo-Lite products during the years these formulations contained asbestos faced the most direct and consistent occupational exposure. Three trade groups in particular bore a disproportionate share of that exposure burden.

Drywall finishers used Durabond extensively at every stage of the finishing process. Mixing the dry powder with water released asbestos fibers into the air. Sanding hardened Durabond compound between coats—a standard, repeated task in any finishing sequence—generated clouds of fine dust that contained respirable asbestos fibers. Because finishers typically worked in enclosed interior spaces with limited ventilation, these fibers could remain airborne for extended periods.

Plasterers who applied Structo-Lite as a basecoat plaster faced comparable risks. Opening and emptying bags of dry Structo-Lite plaster mix released fiber-laden dust. The process of gauging, mixing, and applying the wet plaster also created exposure opportunities, and any subsequent sanding, patching, or mechanical finishing of cured Structo-Lite surfaces compounded that exposure. Plasterers often worked on large wall and ceiling surfaces, repeating these tasks continuously across multi-day or multi-week projects.

Building renovation workers, including general laborers, carpenters, and demolition crews, encountered both products when working in structures built or finished before 1977. Cutting, breaking, grinding, or scraping hardened Durabond or cured Structo-Lite plaster releases asbestos fibers at concentrations that can exceed safe thresholds. Renovation work is considered one of the highest-risk modern exposure pathways because workers may not know that the materials they are disturbing contain asbestos, and older buildings rarely carry warning labels on their existing finishes and plaster systems.

OSHA’s permissible exposure limit (PEL) for asbestos is 0.1 fibers per cubic centimeter of air as an eight-hour time-weighted average. Dry mixing and sanding operations involving asbestos-containing joint compounds and plaster products have been documented in industrial hygiene literature as capable of generating airborne fiber levels well in excess of that threshold without adequate respiratory protection and engineering controls.

United States Gypsum Corporation established the United States Gypsum Asbestos Settlement Trust to compensate individuals who developed asbestos-related diseases as a result of exposure to USG asbestos-containing products, including Durabond and Structo-Lite. This trust was created as part of USG’s resolution of asbestos liability and operates under guidelines that define eligible claimants, qualifying disease categories, and required evidence of product exposure.

USG Durabond and Structo-Lite are specifically recognized products for purposes of filing with the United States Gypsum Asbestos Settlement Trust.

Eligible Disease Categories

The trust accepts claims involving the following asbestos-related diagnoses, subject to its medical and exposure criteria:

  • Mesothelioma — malignant mesothelioma of the pleura, peritoneum, or pericardium
  • Lung cancer — primary lung cancer with documented asbestos exposure history
  • Asbestosis — pulmonary fibrosis attributable to asbestos inhalation, confirmed by imaging and/or pathology
  • Other asbestos-related conditions — including pleural disease, pleural plaques, and diffuse pleural thickening, evaluated under the trust’s specific criteria

Filing Eligibility

To file a claim, individuals (or their surviving family members) generally must demonstrate:

  1. A qualifying medical diagnosis confirmed by appropriate clinical documentation
  2. A documented occupational or environmental history of exposure to USG products, including Durabond or Structo-Lite
  3. Compliance with the trust’s statute of limitations and submission requirements

Claims are processed under the trust’s Trust Distribution Procedures (TDP), which govern payment levels, expedited review options, and the individual review process for claims that fall outside standard criteria.

How to Begin

Individuals who worked as drywall finishers, plasterers, or renovation workers with documented or probable exposure to pre-1977 USG Durabond or Structo-Lite products should consult an attorney experienced in asbestos trust fund claims. An attorney can help gather employment records, medical documentation, and product identification evidence needed to support a complete filing with the United States Gypsum Asbestos Settlement Trust. There are no upfront costs in most asbestos cases, as attorneys typically work on a contingency basis.