{"data":{"id":"us-nyc/n.y.c.-admin.-code-mc-406","jurisdiction":"us-nyc","citation":"N.Y.C. Admin. Code § MC 406","heading":"Section MC 406: Ventilation of Uninhabited Spaces","body":"406.1 General.\n\nUninhabited spaces, such as crawl spaces and attics, shall be provided with natural ventilation openings as required by the New York City Building Code or shall be provided with a mechanical exhaust and supply air system. The mechanical exhaust rate shall be not less than 0.02 cfm per square foot (0.00001 m\n\t\t\t\t\t\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t\t\t\t\t\t3\n\t\t\t\t\t\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t\t\t\t\t\t/s • m\n\t\t\t\t\t\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t\t\t\t\t\t2\n\t\t\t\t\t\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t\t\t\t\t\t) of horizontal area and shall be automatically controlled to operate when the relative humidity in the space served exceeds 60 percent.\n\n406.1.1 Methane and radon venting.\n\nThe design and materials used in the installation of the methane and radon vent systems shall be approved by the commissioner and shall comply with all applicable rules of the Fire Department.","path":["New York City Administrative Code","Title 28","Chapter 8: New York City Mechanical Code"],"source_url":"https://files.amlegal.com/pdffiles/NewYorkCity/Admin/XML.zip","current_through":"Local Law 2026/135 (enacted August 31, 2026)","vintage":"","retrieved_at":"2026-09-06T02:48:57Z","sha256":"d72d6e56041537e54b65e3009654dca0034155df525c801e2512e4fc492a66c2","source_id":"us-nyc","stale":false,"prev":"us-nyc/n.y.c.-admin.-code-mc-405","next":"us-nyc/n.y.c.-admin.-code-mc-407"},"notice":"GroundRules: Original legal text. Not legal advice."}