In the United States, most state and local laws regarding the required number and placement of smoke detectors are based upon standards established in Article 72 of NFPA fire code.

In older existing homes, smoke detectors are generally required on every habitable level and within the vicinity of all bedrooms. In new construction, the minimum requirements are typically much greater. All smoke detectors must be hooked directly to the electrical wiring and be interconnected. In addition, smoke detectors are required inside every bedroom.

Laws governing the installation of smoke detectors vary depending on the locality. Homeowners with questions or concerns regarding smoke detector placement are encouraged to contact their local fire marshal or building inspector for assistance.  It is recommended that smoke detectors should not be placed in kitchens and bathrooms, because the steam would often set them off.