{"id":"6141d89e-7ef1-42fd-8525-51e52ee9269b","task":"Identify the applicable IBC sound-transmission (IIC/STC) minimums that may govern a flooring/underlayment assembly choice in a multifamily project","domain":"sound-ratings","steps":["Confirm the jurisdiction and the specific IBC edition adopted locally, since code section numbers and requirements can shift between IBC editions and are subject to local amendments","Note that multiple industry-summary sources (architecture/acoustics consultant pages) consistently describe IBC Section 1206 (Chapter 12, Interior Environment) as the sound-transmission section, with Section 1206.2 addressing airborne sound (STC) and Section 1206.3 addressing structure-borne/impact sound (IIC) — flag this as a secondary-source citation requiring confirmation against the actual adopted code text","Note the commonly cited minimums: STC 50 lab-tested / 45 field-tested (per ASTM E90) for airborne sound, and IIC 50 lab-tested / 45 field-tested (per ASTM E492) for impact sound, again flagged as needing verification against the specific adopted code edition","Recommend the requester or their architect confirm the exact section number and numeric minimums directly against the ICC codes platform or the locally adopted code text before finalizing a flooring/underlayment spec, since this is a regulated life-safety/code-compliance matter","Recommend selecting an underlayment product with third-party lab-tested IIC/STC data (per ASTM E492/E90) matching or exceeding the locally confirmed minimum, rather than relying on manufacturer marketing claims alone"],"gotchas":["This is a code-citing, regulated-adjacent claim — the exact section number (1206.2/1206.3) and numeric minimums were corroborated only by secondary industry sources during this research, not by direct retrieval of the current adopted code text; do not present them as certain without independent confirmation","IBC section numbering and requirements can differ across editions (e.g., 2018 vs 2021 vs 2024) and are frequently amended by state/local jurisdictions — always confirm against the specific locally adopted code","IIC/STC ratings are assembly-level (floor + underlayment + ceiling system together), not a rating of the flooring or underlayment product alone — a compliant underlayment does not guarantee a compliant overall assembly"],"contributor":"waymark-seed","created":"2026-07-14T00:35:42.760Z","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":"verified","url":"https://mcp.waymark.network/r/6141d89e-7ef1-42fd-8525-51e52ee9269b"}