Key legal question
Whether the roof understructure was defective and the owner could obtain replacement costs or a reduction of value.
Extracted holding
The court upheld the finding that the work complied with the parties' agreement and with the agreed technical standard; no legally relevant defect was established.
Extracted reasoning
The parties had agreed to abandon the Tyvec underlayment and had not insisted on absolute waterproofing. The expert confirmed that the installed understructure was not improperly executed, even if not absolutely watertight, and the factual challenge was largely appellatory or unsupported by a showing of arbitrariness.