Old buildings and new codes.

Building codes change. The building you insured ten, twenty, or fifty years ago was very likely built to a different, usually less demanding, code than the one in effect today. Standard property insurance was never built to account for that gap, and most policies exclude it outright.

Ordinance and law coverage is the endorsement that fills it. It typically addresses three distinct costs that show up after a significant loss to an older building: the cost of demolishing the undamaged portion of the building if code requires full demolition rather than partial repair, the increased cost of construction to rebuild to current code rather than the original one, and, in some forms, the loss of value in the undamaged portion of the building that has to come down anyway.

Without this endorsement, a property policy generally pays to repair or rebuild what was damaged, to the standard it was originally built to, nothing more. If code now requires updated electrical systems, fire suppression, accessibility features, or structural reinforcement that wasn't required when the building went up, that additional cost is the owner's, in full, at exactly the moment they can least afford an uninsured expense.

This coverage matters most for exactly the buildings owners are least likely to think about it for: the ones that have been standing, and insured the same way, for a long time. A newer building is less likely to be meaningfully behind current code. An older one, especially one that's never been fully renovated, is a much more likely candidate for a real gap here.

If you don't know whether your policy includes ordinance and law coverage, and at what limit, that's worth finding out before you need it rather than after.