PRESTON HEALTH SERVICES ARCHITECT S NO. 2700

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1 SECTION HVAC INSULATION PART 1 - GENERAL 1.1 DESCRIPTION OF WORK: A. All work covered in this section consists of furnishing all labor, equipment, materials and accessories, and performing all operations required, for the correct fabrication and installation of thermal insulation applied to piping, equipment, and ductwork. 1.2 DEFINITIONS: A. Exposed piping and ductwork is that which can be seen when the building is complete without opening or removing access door panels, or ceilings tiles. This also includes all mechanical equipment rooms and pipe tunnels. B. Concealed piping and ductwork are those elements above ceilings, in chases, interstitial space and pipe spaces. Other piping and ductwork is considered to be exposed. C. Exterior piping and ductwork is that which is exposed to the weather and/or outside the building envelope. Piping and ductwork protected by overhangs, areaways, etc., exterior to the building envelope are considered exterior. D. ASJ: All service jacket, white finish facing or jacket. E. Air conditioned space: Space directly supplied with heated or cooled air. F. Cold: Equipment, ductwork or piping handling media at design temperature of 60 degrees F or below. G. FRK: Foil reinforced kraft facing. H. FSK: Foil-scrim-kraft facing. I. Hot: Ductwork handling air at design temperature above 60 degrees F; equipment or piping handling media above 105 degrees F. J. Pcf: Density, pounds per cubic foot. K. Runout: Branch pipe connection up to one inch nominal size to a one terminal piece of equipment (fan coil, terminal box). L. Thermal conductance: Heat flow rate through materials. 1. Flat surface: BTU per hour per square foot. 2. Pipe or cylinder: BTU per hour per linear foot. 3. Thermal conductivity (k): BTU per inch thickness, per hour, per square foot, HVAC INSULATION

2 1.3 QUALITY ASSURANCE: per degree Fahrenheit temperature difference. A. Products of the manufacturers, herein, will be acceptable for use for the specific functions noted. All materials shall be compatible with the materials to which they are applied, and shall not corrode, soften or otherwise attack such materials in either the wet or dry state. B. Materials shall be applied subject to their temperature limits. Any methods of application of insulation materials or finishes not specified in detail herein shall be in accordance with the particular manufacturer's published recommendations. C. Insulation shall be applied by experienced workers regularly employed for this type work. 1.4 RATING: A. All insulation shall have composite surface burning characteristic rating as tested by ASTM E 84, UL 723, or NFPA 255 not exceeding: Flame Spread 25 Smoke Developed 50 B. Composite shall include insulation, jacketing and adhesive used to secure jacketing or facing. All accessory items such as PVC jacketing and fittings, adhesive, mastic, cement, tape and cloth shall have the same component rating as specified above. 1.5 STANDARDS: A. ANSI/ASHRAE Standard Energy Standard for Buildings Except Lowrise Residential Buildings. B. Midwest Insulation Contractors Association Commercial and Industrial Insulation Standards - Third Edition. 1.6 SUBMITTALS: A. Submittals shall include all materials used, including: 1. Insulation 2. Jacketing 3. Tapes 4. Hardware 5. Mastics 6. Adhesives B. Submittals shall be formatted to include a list of materials for each service: C. Submittals shall use pages from Midwest Insulation Contractors Association - HVAC INSULATION

3 PART 2 - PRODUCTS Commercial and Industrial Insulation Standards for defining how insulation materials will be applied. 2.1 GLASS FIBER INSULATION: A. Piping: 1. Nominal minimum thicknesses are listed in the table at the end of this section. These thicknesses are based on insulation having a thermal resistivity between 4.0 to 4.6 sq. ft.-hr.-f/btu-in. on a flat surface resistivity to maintain equivalent insulation value. 2. Insulation shall be 850 deg. F rated as manufactured by Owens Corning, Manville or Knauf. 3. Insulation shall have factory-applied, reinforced, flame retardant, vapor barrier jacket equal to Owens-Corning ASJ with selfsealing lap. Butt joints shall be taped with field-applied ASJ tape 3 in. wide. 4. Refer to the table at the end of this section for required pipe insulation thicknesses. 5. Routed or molded fitting insulation shall be Hamfab. B. Ductwork (Insulation): 1. Insulation shall be 250 deg. F rated as manufactured by Owens Corning, Manville, Knauf, or Certainteed. 2. Duct Wrap: 2 in. thick, 1.0 PCF with aluminum or FRK facing, having a maximum vapor transmission of.02 perms. 3. Insulation Board: 2 in. thick 3 PCF with FRK facing. 2.2 ELASTOMERIC CLOSED CELL INSULATION: A. Tubing and Sheet insulation shall be flexible fire retardant closed cell, conforming to ASTM C 534, and ASTM Thermal resistivity shall be 3.70 sq.ft.-hr-f/btu-in. Insulation shall be Rubatex or Armaflex. 2.3 FINISHES: A. Metal jacketing, smooth.016 in. thick, type T 3003 aluminum with laminated moisture barrier. Jacketing shall be Childers, aluminum roll jacketing with Polykraft moisture barrier. Jacketing shall be embossed "No Asbestos" on a 6 inch spacing. B. Metal fitting covers shall be two piece aluminum. Covers shall be Ell-Jac. HVAC INSULATION

4 C. Foil scrim kraft (FSK) jacket, flame retardant vapor barrier. Jacket shall be Alpha Temp 10651, all service jacket. D. Fitting covers shall be one piece 20 mil PVC, covers shall be Ceel-Tite 550 PVC-UVR by Ceel-Co. Zeston and Proto are approved equals. E. Water based latex enamel equal to Armstrong WB Armaflex Finish. 2.4 MISCELLANEOUS: A. Adhesives: 1. Glass & Mineral Fiber - Foster / Vimasco Cellular Glass - Pittcote 300 / Childers CP-30. B. Mastic (Weather Barrier): 1. Foster Mastic / Vimasco. 2. Childers Vi-Cryl CP10/ Vimasco WC-5. C. Coatings: 1. Foster - Monolar Coating / Vimasco 2. Foster Sealfas / Vimasco 3. Foster Tite-Fit / Vimasco 4. Pittcote 300 D. Vapor Barrier Sealant: Foster Flextra E. FSK tape 3 in. wide, equal to Nashua FSK. F. Insulpins G. Roll on Corner bead (2 in. x 2 in., 26 ga. galvanized steel). H. Fiber reinforced tape - Nashua 357, or 398. I. Insulation protection shields - Grinnell fig 167. J. Rigid insulation inserts - Hamfab. K. Reinforcing Cloth - Vimasco, Elastafab 894, conforming to ASTM D1668. L. Bands in., aluminum, ½ in. wide, embossed continuously with the legend "No Asbestos". M. Hexagonal Wire Netting - One inch mesh, 22 ga. galvanized steel. HVAC INSULATION

5 PART 3 - EXECUTION 3.1 GENERAL: A. Insulation shall be applied to clean and dry surfaces after tests and approvals required by this specification have been completed. B. On cold surfaces where a vapor barrier must be maintained, insulation shall be applied with a continuous, unbroken moisture and vapor seal. All hangers, supports, anchors, or other projections that are secured to cold surfaces shall be insulated and vapor sealed to prevent condensation. C. All surface finishes shall be extended in such a manner as to protect all raw edges, ends and surfaces of insulation. D. All pipe or duct insulation shall be continuous through walls, ceiling or floor openings, or sleeves; except where firestop or firesafing materials are required. E. Metal shields shall be installed between hangers or supports and the piping insulation. Rigid insulation inserts shall be installed as required between the pipe and the insulation shields. Inserts shall be of equal thickness to the adjacent insulation and shall be vapor sealed as required. F. Size insulation to cover electric heat tracing on piping where it is specified. G. All clevis type pipe supports shall be sized to fit the outside diameter of the insulation. H. Insulate valves, fittings, flanges etc. with the same thickness of insulation as specified for piping. I. Install longitudinal jacketing laps to shed rainwater. J. Insulate items mounted in ductwork with the same thickness of insulation as specified for ductwork: including air measuring stations, smoke dampers, and automatic dampers. K. Repair insulation damaged by work under this contract to match existing work or replace damaged portion with insulation specified for new work. L. Standing seams and other projections in ductwork or casings shall have insulation applied so that at least ½" of insulation will cover such projections. M. Where ductwork is lined, no thermal insulation is required. N. Where unlined duct and lined duct connect, the insulation shall overlap lined section at least 6". O. Piping and ductwork covered with metal or P.V.C. jacketing systems shall have the joints made to shed water. Laps shall be positioned in the bottom quadrant on HVAC INSULATION

6 horizontal pipe and ductwork. 3.2 HVAC SYSTEMS: A. Concealed Ductwork: 1. Apply jacketed ductwrap to all concealed ductwork providing conditioned air, or outside air. Insulate return ductwork in non-conditioned spaces and in ceiling spaces below a roof. 2. Pull insulation snug, but do not compress insulation more than 1/4 inch. 3. Secure ductwrap insulation to ductwork using adhesive. Secure insulation on bottom on sides of horizontal ductwork and all sides of vertical ductwork with insulpins welded to duct on 12 to 18 inch centers and with clips slipped over the pins. Apply clips without compressing insulation. Make joints by lapping the facing a minimum of 2 inch and stapling with T-5 flared staples. Vapor - seal with Childers CP-30 Low Odor at all staples, clip locations and other penetrations. Seal joints with 3 inch wide FSK tape. 4. See schedule at end of this section for insulation thicknesses. B. Exposed Interior Ductwork: 1. Apply insulation board with FRK facing to all exposed ductwork providing conditioned air, or outside air. Insulate return ductwork in non-conditioned spaces. 2. Secure insulation with insulpins (all surfaces) welded to duct on 12 to 18 in. centers and with clips slipped over pins. Seams and joints shall be vapor sealed with 3 in. wide FSK tape. Corners and edges of ductwork shall be reinforced with roll-on corner bead. 3. Seal all break and punctures with vapor barrier sealant and FSK tape. 4. See schedule at end of this section for insulation thicknesses. C. Expansion Joints/flexible Connectors: 1. Insulate expansion joints with oversized sections of molded insulation. Use same material as on adjacent piping. Allow for pipe growth, and contraction. 2. Insulate flexible connectors with a flexible material as follows: Service Refrigerant Suction Lines Insulation 3/4" Elastomeric Tubular D. Elastomeric: HVAC INSULATION

7 1. Apply closed cell elastomeric insulation to all pipes, equipment and surfaces listed below. 2. Secure insulation with contact adhesive in accordance with manufacturers instructions. 3. Insulate fittings and valves with miter cut pieces of insulation same thickness as piping. 4. DX Systems: a. Apply one layer of 1 inch thick elastomeric closed cell tubular insulation to the refrigerant suction line, and the refrigerant liquid line after the expansion valve. 5. Cooling coil condensate piping - 1 in. thick 6. Covers and caps for all valve stems and operators, gauge cocks, thermometer wells and other appurtenances subject to sweating. E. Finishes: 1. Metal Jacketing (Aluminum): a. Cover the following insulated systems with metal jacketing: (1) Piping installed outdoors b. Cover with.016 in. thick aluminum jacket and hold in place with 2 in. wide aluminum bands on 9 in. centers. Fittings shall be covered with mitered segments of jackets or two piece preformed fitting covers. Provide angle ring escutcheons at wall, ceiling or floor penetrations. c. Machine cut the jacket to produce a straight, smooth edge. Lap longitudinal and circumferential seams not less than 2 in. Install jackets on horizontal piping with the longitudinal seam approximately midway between horizontal centerline and the bottom side of pipe. Install with the top edge of jacket overlapping the bottom edge of jacket and with the seam of each jacket slightly offset from the seam of the adjacent jacket. Install jackets on vertical piping and on piping pitched from the horizontal from low point to high point so that the lower circumferential edge of each jacket overlaps the jacket below it. 2. Metal Jacketing (Galvanized): a. Insulated ductwork installed outdoors![and insulated ductwork within 8 ft. of the finished floor in a mechanical room] shall be covered with 30 gauge galvanized steel. Covering shall be HVAC INSULATION

8 hemmed, and flanged. Secure with self tapping screws on eight inch centers. Do not puncture vapor barrier. 3. All Service Jacket/fitting Covers: 4. Paint: a. Exposed piping finish covering indoors shall be the All Service Jacket. Fittings shall be covered with molded fitting covers. b. Concealed Piping finish covering shall be the All Service Jacket. Fittings shall be covered by wrapping the fitting with fiber reinforced tape, with a 5 percent overlap. c. Pipe fittings larger than cataloged aluminum two piece or PVC covers shall be covered with vapor barriers mastic for cold lines, or two layers of hydraulic cement reinforced with wire mesh and finished with vinyl acrylic weather barrier mastic. a. Exposed or exterior installations of elastomeric closed cell insulation shall be painted with two coats of water base latex enamel. MINIMUM DUCT INSULATION REQUIREMENTS EXTERIOR ATTIC UNCONDITIONED SPACES INSIDE CONDITIONED SPACES SUPPLY DUCT Duct wrap -- 4" 2" 2" Rigid board 2" -- 2" 2" RETURN DUCT Duct wrap -- 2" 2" 1" Rigid board 2" OUTSIDE AIR Duct wrap -- 2" 2" 2" Rigid board 2" EXHAUST DUCT Duct wrap -- 1" 1" -- Rigid board 1" END OF SECTION HVAC INSULATION