Orange County NC Website
Browse       Search
NCHFA HOUSING REHABILITATION PROGRAMS -- Energy Standards <br /> vapor retarder. <br /> 2.2.3 If interior surfaces of exterior walls, or interior walls separating <br /> unconditioned space from conditioned space, are to be replaced, cavities shall <br /> be insulated with R-13 unfaced Batts and continuous 6-mil poly vapor retarder. <br /> 2.2.4 If exterior siding is to be removed and replaced, cavities shall be <br /> insulated to R-13 with kraft- or foil-faced Batts and sheathed with R-3 <br /> (minimum) rigid foam board. If exterior siding is to be covered with new <br /> siding, cavities shall be insulated with blown-in dense-pack cellulose or <br /> approved alternative. <br /> 2.2.5 Uninsulated masonry block exterior walls should be treated by <br /> installing pressure-treated one-by (minimum) nailing strips vertically, no more <br /> than 24" o.c., on interior block surfaces, with 3/4" foam board insulation <br /> between nailers. If space and funds permit, it is preferable to construct a stud <br /> wall inside the existing exterior block wall and insulate with R-13 batts.) A <br /> continuous polyethylene moisture barrier must be stapled to the nailers prior to <br /> installation of finished wall material (sheetrock or paneling). <br /> 2.3 Insulation of FIoors. Kraft- or foil-faced R-19 insulation or approved <br /> alternative shall be installed between floor joists (with facing up) of all <br /> conditioned areas over basements, cantilevers or crawlspaces with 18" <br /> clearance or more. To include mudsill/band areas and through cross bridaina. <br /> 2.4 Insulation of Windows and Doors. <br /> 2.4.1 When windows or exterior doors are to be installed in new locations, <br /> 1/2"-1" rigid foam insulation board should be sandwiched between two-bys of <br /> headers. <br /> 2.4.2 When window casings are to be removed and/or replaced for any <br /> reason, all voids shall be filled with non-expanding insulating foam sealant or <br /> an approved alternative and a continuous 6-mil poly vapor retarder installed <br /> between framing and jambs. <br /> 2.5. Insulation of Ducts. <br /> 2.5.1 After sealing (see 2.5.3, below), all accessible heating and air <br /> conditioning ductwork shall be insulated to R-8 in unconditioned space or R-6 <br /> in conditioned space. Vertical clearance of (18" or more shall be deemed <br /> "accessible" in attics or crawlspaces. <br /> 4 <br />