Allowing unhoused in uninhabitable structures

Are there any jurisdictions that have a code that specifically prohibits a person from allowing tenancy of an uninhabitable building/structure on their property? rnI’m sure we are not the only city where people, in an effort to help the unhoused, are allowing friends or strangers to “stay” in a garage or shed. Just looking for examples of language for a local code. Currently we must use IRC, IPMC, UHC and various RCWs to deal with this issue. rn