Can bushings be used in residential gas piping systems?
Yes, according to the Michigan Residential Code (MRC). The majority of inspector attendees at the meeting believed that bushings should not be used and would like to see a change in the code. • Is insulation required on bathroom exhaust ventilation ductwork? No, there is no regulation in the MRC or the Michigan Mechanical Code (MMC) that requires the use of insulation on bathroom exhaust ventilation ductwork. Attendees were split about 50/50 on whether this code should be changed. • Is combustion air required during furnace replacement in homes built before 1976? Yes, the MRC, MMC, and the International Fuel Gas Code (IFGC) all have sections that require the use of combustion air for the installation of fuel-burning appliances. • Do residential duct joints and seams need to be sealed? Yes, joints of duct systems shall be made substantially airtight by means of tapes, mastics, gasketing, or other approved closure systems. MIAM materials state, “According to HVAC industry studies, leakag
