Contractual Liability Coverage Under Builder's Warranty to Insured Homeowner

We have a question about coverage under the contractual liability provision of a homeowners policy. The insured was building his dream house. When the home was almost fully completed and the insured had already moved in, he noticed some defects on the home's exterior. This led to a thorough inspection of the home. Numerous serious defects were noted, including improper roof sheathing and improper exterior wall sheathing.

The insured has a signed warranty from the builder. Under the theory that this warranty constitutes a written contract relating to the ownership, maintenance, or use of the insured location that was entered into before a loss, the insured is arguing that he is now due contractual liability coverage for his future liability to a future buyer.