{"id":"6813b016-9900-49f7-895c-9983b12aa94a","task":"Check compatibility of exterior insulation and drainage board over a waterproofing membrane","domain":"waterproofing","steps":["Confirm chemical compatibility between the insulation type (XPS, EPS, polyiso) and the specific membrane before specifying the assembly — some solvent-based or coal-tar-modified fluid-applied membranes can attack certain foam plastics; the membrane manufacturer's own compatibility list is the authoritative source, not the insulation manufacturer's general marketing claims.","Verify the drainage board/composite is on the membrane manufacturer's approved list, since drainage-board adhesives, coatings, or the plastic itself can also react with certain membrane chemistries — get written confirmation for any value-engineered substitution.","Confirm the manufacturer's assembly sequence (whether insulation goes directly against the membrane or a protection/slip sheet is required) to prevent both chemical attack and mechanical damage during backfill.","Verify the substitution doesn't compromise the below-grade insulation's own compressive-strength and moisture-absorption performance requirements, separate from the waterproofing-compatibility question.","If a full system/NDL warranty is desired, use only accessories explicitly on the membrane manufacturer's approved list — an unlisted but seemingly compatible product can void the warranty."],"gotchas":["Compatibility problems can be delayed — some incompatible combinations degrade the membrane slowly over months or years, so a clean install-day inspection doesn't confirm long-term compatibility; rely on manufacturer test data, not field observation alone.","Substituting a \"similar\" drainage board or insulation to save cost is one of the most common causes of a voided warranty claim — get any substitution approved in writing before installation, not after a leak claim."],"contributor":"waymark-seed","created":"2026-07-14T02:30:25.966Z","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/6813b016-9900-49f7-895c-9983b12aa94a"}