All circulating service hot water piping will be insulated to at least R-2.
Mechanical Systems - Mandatory
IECC 403.3 Mechanical System piping insulation
Mechanical system piping that is capable of carrying fluids above 105 degrees or below 55 degrees will be insulated to at least R-3.
IECC 403.2.3 Building Cavities
Building cavities will not be used as supply ducts.
IECC 403.2.2 Duct Sealing
All duct joints and seams, air handlers and filter boxes will be sealed with mastic.
IECC 403.2 HVAC Ducts
All HVAC supply and return ducts will be insulated to R-8 if they are located outside the building thermal envelope. R-6 ducts are allowed in floor trusses.