​The 2012 Mechanical Code became effective September 1, 2011 and mandatory June 1, 2012.

Here are some of the new code sections or changes in the 2012 North Carolina Mechanical Code.  This list is not intended to be a complete list of changes.

  1. 304.6 Appliances located in public garages, repair garages and similar facilities shall be located a minimum of 8 feet above the floor and where vehicles are capable of passing under the appliance shall be located a minimum of 1 foot higher than the door opening.
  2. 304.10.3 Appliances located in a crawl space shall be supported at each corner with a minimum of 8-inch x 8-inch support. The unit shall be a minimum of 2 inches above grade. If the opening height will not keep the ducts a minimum of 4 inches above grade, the appliances shall be supported to provide the minimum 4 inches clearance required for the ducts.
  3. 312.1 For one- and two- family dwellings and townhouses, heating and cooling equipment shall be sized in accordance with ACCA Manual S based on building loads calculated in accordance with ACCA manual J.
  4. 504.6.1 Dryer Exhaust ducts shall have a smooth interior finish and shall be made of metal a minimum of .016-inch thickness. The duct shall be a minimum of 4 inches in diameter.
  5. 504.6.2 Dryer exhaust ducts shall be supported at 4 foot intervals and secured in place and terminate not less than 12 inches above finished grade.
  6. 504.6.3 Transition ducts for dryers shall be a single length that is listed and labeled in accordance with UL2158A. The transition ducts cannot exceed 8 feet in length, shall remain in the same room as the appliance and shall not be concealed by construction.
  7. 504.6.4 The maximum allowable exhaust duct length shall be determined by one of the methods specified in 504.6.4.1 or 504.6.4.2. 

         a. 504.6.4.1 The maximum length of the exhaust duct shall be 35 feet from the connection to the transition duct to the outlet terminal. Where fittings are used, the maximum length of the duct may be reduced in accordance with Table 504.6.4.1. 

          b.  504.6.4.2 The maximum length of the duct shall be determined by the    manufacturer’s installation instruction. The Code Official shall be provided with a copy of the installation instruction for the make and model of the dryer. If the exhaust duct is to be concealed, the Code Official shall be provided the installation instructions prior to the concealment inspection.
  8. 504.6.5 The equivalent length of the dryer exhaust duct shall be identified on a permanent tag or label. The tag or label shall be located with 6 feet of the exhaust duct connection.
  9. 505.2 Domestic kitchen exhaust hoods capable of exhausting in excess of 400 cfm shall be provided with makeup air. The makeup air systems shall be equipped with a means of closure and shall be automatically controlled to start and operate simultaneously with the exhaust system.