Pre-Coat Lath Inspection on a New Build
A new 3,000-square-foot house is being finished with three-coat stucco over wood frame. The inspector is called after building paper and metal lath are installed but before the scratch coat. The general contractor wants a verbal OK that day. Observations: horizontal building-paper laps at two locations are reversed, with the upper sheet behind the lower sheet; lath fasteners are spaced about 12 inches vertically and 24 inches horizontally, and several miss framing; lath laps at the corners are less than 2 inches; the rear wall terminates at the slab with no weep screed; a 32-foot-long unbroken wall has no control joint; window casing beads are set but sealant is not yet installed. The contractor says the plaster will cover everything.
1. Which observations are stop-work items before scratch coat, and which can be corrected later? Explain your reasoning.
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Stop-work items before scratch coat include the reversed building-paper laps, the missing weep screed at the rear wall, the sparse and missed lath fasteners, and the inadequate lath laps. Those defects will be concealed by the scratch coat and cannot be reliably corrected later without removal. The missing control joint on a 32-foot unbroken wall should also be resolved before plastering, because control joints are installed through the stucco and must be planned with the lath. The window sealant is not a stop-work item at this stage; it is a later weatherproofing step. My reasoning is that the scratch coat locks in the water-resistive barrier, the lath embedment, and the base termination. Once covered, an inspector can no longer verify laps, fastening, or clearance.
2. Would you give verbal approval? What would you require and how would you document it?
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I would not give verbal approval. I would issue a written pre-coat inspection report with photo references and a punch list, and require correction and reinspection before scratch coat. The report should distinguish defects that violate the manufacturer's lath and accessory requirements from workmanship issues, and it should note that the sealant is still pending. I would ask the contractor to provide the lath manufacturer's fastening schedule and the stucco assembly details so the corrections can be verified, not just promised. If the contractor proceeds without correction, I would document that in the report and notify the owner. A verbal OK is risky because it can be remembered as approval of a wall that was not ready.
3. What is the risk if the scratch coat proceeds, and how should the report address that risk?
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If the scratch coat proceeds, the reversed paper can direct water inward, the missed fasteners can allow lath movement and cracking, the short laps can open at corners, and the buried base can trap water. The control-joint omission can lead to random cracking. The inspection report should be clear that the wall is not ready for scratch coat and that reinspection is required. I would list each location, the observed condition, and the correction needed. I would not accept the claim that the plaster will cover it as a response, because coverage is exactly why the defects must be corrected now.