{"id":"890a4c1a-8438-41d9-be6c-d7a2aa9f5d37","task":"Select and place waterstops at below-grade concrete construction and expansion joints","domain":"waterproofing","steps":["Use PVC waterstops (heat-welded at joints/intersections for a continuous diaphragm) as the industry-standard flexible type for below-grade construction and cold joints — ACI 350 (Code Requirements for Environmental Engineering Concrete Structures) is a commonly cited acceptance reference; confirm the current edition on concrete.org before citing a specific provision.","Use hydrophilic waterstops (rubber or bentonite-enhanced strips that swell on contact with water) at non-moving construction (cold) joints where they don't need to be secured/centered ahead of the pour the way ribbon PVC waterstops do.","Match waterstop type to joint type: expansion/movement joints generally need a flexible center-bulb elastomeric waterstop designed to accommodate movement; construction joints between sequential pours are commonly served by PVC ribbon or hydrophilic strip waterstops.","Maintain continuity around the entire joint, including corners and intersections, with proper factory- or field-welded/spliced connections at direction changes — an interrupted or poorly spliced corner is a common leak path.","Ensure proper concrete consolidation (vibration) around ribbed PVC waterstops during placement — voids/honeycombing against the waterstop from inadequate consolidation is a common as-built defect."],"gotchas":["Hydrophilic waterstops can prematurely swell if exposed to rain/moisture before the second pour encases them, reducing or eliminating their sealing ability — protect them from moisture between placement and pour.","Confirm waterstop type and detailing against the current ACI standard and the structural engineer's joint-movement design — don't treat it as a purely material/vendor-catalog decision."],"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/890a4c1a-8438-41d9-be6c-d7a2aa9f5d37"}