Provide for review a list of all pipe and duct systems with a brief justification of insulation and thickness, or of no insulation if none is specified.
Include all field insulated equipment on the list.
As a minimum, insulation thickness to meet the requirements of the State Energy Code.
The insulation and jacketing shall be resistant to moisture and mold and shall be resistant to damage or deterioration under the service intended. Materials shall meet the smoke and flame spread ratings required by the governing codes.
Closed cell plastic insulation is preferred on refrigerant piping and cold equipment.
Surfaces, which will operate within 10 degrees F. of the ambient dew point, shall have a vapor barrier over the insulation.
Surfaces better than 90 degrees F. shall be insulated as required to protect personnel and/or conserve energy.
Insulation exposed to weather or to physical damage shall have suitable protection.
Aluminum jackets secured with aluminum bands on 12" centers with longitudinal seams lapped and turned down shall be installed on all piping exposed to weather. Provide similar protection at all valves, fittings, and flanges.
Insulation shall be installed such that service and maintenance points such as valve handles, access doors, pressure and temperature fittings, lubrication fittings, and strainers remain accessible without disturbing the insulation.
Vapor barrier jackets shall be sealed at locations to prevent the intrusion of moisture.
Use factory made PVC covers at fittings, flanges, and all other irregular shapes for which they are available.
Specify structurally rigid insulation sections at all hangers and supports to prevent damage to the insulation and jackets.
Size hangers and supports to go outside the insulation.
Provide steam traps 1” and over with snap on insulation.
Provide a vapor seal design at strap or rod hangers and a thermal conduction barrier at trapeze hangers and supports.
Require extra erosion protection at the upstream edge of duct lining sections such as a sheet metal flashing.
Internally lined ductwork
Internally lined ductwork shall be avoided, except when used for sound attenuation or when used in areas where external insulation is subject to damage (such as mechanical rooms).
Where internal insulation is used provide Mylar facing to allow cleaning.
Provide perforated liner over internal insulation inside mechanical units.
Access will be provided at elbows, turning vanes, and locations where debris collects.
Other sound isolation is anticipated when the insulation is external.
Use a maximum of six feet of flexible ductwork on diffuser and grille run outs.
Coordinate insulation and equipment specifications to be sure that the required insulation is field applied if equipment is not factory insulated.
Equipment such as chilled water pumps or heat exchangers which must be completely insulated shall be provided with boxed insulation which is designed and marked so it can be removed and replaced without destroying the utility and appearance, except for repairs needed on the jacket.
Chilled equipment insulation must not have voids, pockets, or air space that can allow condensation to form.