Landlords are responsible for maintaining fit and habitable housing and repairing rental property, and this extends to fixing leaking pipes, windows, and roofs -- the causes of most mold. If the landlord doesn't take care of leaks and mold grows as a result, you may be able to hold the landlord responsible if you can convince a judge or jury that the mold has caused a health problem. However, landlord responsibilities regarding mold are not always clearly spelled out in building codes, ordinances, statutes, or regulations. Be aware that responsibility may change when mold grows as the result of tenant behavior, such as keeping the apartment tightly shut, creating high humidity, or failing to maintain necessary cleanliness. When a tenant's own negligence is the sole cause of injury, the landlord is not liable. Visit nyc.gov/health for the complete â€œMold Guidelinesâ€ or call 311.