What is constructive eviction and when does it apply?

Constructive eviction occurs when a landlord's actions or failure to act make the property substantially uninhabitable, effectively forcing the tenant to leave. Examples include failing to repair a broken heating system in winter, persistent water leaks causing mold, or allowing conditions that violate health codes. To claim constructive eviction, the tenant must notify the landlord of the condition, allow reasonable time for repair, and actually vacate the property. If the tenant stays, the claim fails.