HVAC installation shall comply with the provisions of the IRC or the applicable mechanical and/or energy code. SIP homes require no special heating system. Forced air, electric, solar, radiant and wood burning systems are all suitable, though some are more appropriate than others for a specific home design. Central air conditioning requires ductwork and is therefore most compatible with forced-air heating systems. Because of the home’s tight construction, the fireplaces, wood burners, furnaces and any other combustion appliances should be supplied with an outside source of combustion air.