Here is a link to a sample Homeowner's policy: https://www.iii.org/sites/default/files/docs/pdf/HO3_sample....
Exclusion B on page 12 is probably the relevant section. It excludes loss due to "Faulty, inadequate or defective:... workmanship, re- pair, construction, renovation, remodeling,..." but also contains an "ensuing loss" exception.
Here is an article about that: https://www.irmi.com/articles/expert-commentary/ensuing-loss...
> A classic example [of an ensuing loss exception] is if faulty repair resulted in improper wiring and the improper wiring caused a fire. Almost every insurer would pay for the fire damage, but not for the repair of the improper wiring.