An insured experienced a sewer backup and called a plumber. The plumber ran a camera down the drain and found that the pipe had rusted and collapsed. The insured is covered by a businessowners policy, BP 00 02 12 99.

The BOP form provides coverage for collapse if caused by hidden decay. However, there is an exclusion under "Other Types of Loss" for rust, decay, deterioration, etc. These two provisions seem to contradict one another.

Should the collapsed drain be covered? What about business income coverage during the down time for repair?