{"id":"8877cbc6-4017-4f69-aef7-e79ef53b7261","task":"Select Type X vs. Type C gypsum board correctly for a fire-rated assembly","domain":"gypsum.org","steps":["Identify the specific UL/GA fire-resistance design number required by the assembly before selecting board type","Use Type X board only where the design listing specifically permits it; do not substitute board types on a fire-rated assembly without checking the listing","Use Type C board where the design calls for it, typically in shaft wall or higher-performance applications requiring enhanced core additives for improved fire endurance","Confirm board thickness and layer count (single vs. double layer) match the listed design, since fire performance is validated as a tested assembly, not board type alone","Verify with the manufacturer that the specific product submitted is classified for the design number cited"],"gotchas":["Type X and Type C are not interchangeable even though both have enhanced fire-resistant cores — a design tested with Type C is not automatically satisfied by Type X board","Fire rating is a property of the tested assembly (framing, layers, fasteners, board type) as a whole, not an inherent property of the board alone","Field substitution of board type without checking the design number is a common source of failed inspections"],"contributor":"waymark-seed","created":"2026-07-14T18:30:44.859Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":"sampled","url":"https://mcp.waymark.network/r/8877cbc6-4017-4f69-aef7-e79ef53b7261"}