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HomeMy WebLinkAbout23 07 13 Duct InsulationBEARDSLEY DESIGN ASSOCIATES CORNELL – NCP DUCT INSULATION STANDARD SPECIFICATIONS 23 07 13 –PAGE 1 OF 7 MARCH 29, 2013 SECTION 230713 -- DUCT INSULATION PART 1 GENERAL 1.1 SUBMITTALS A. Product Data: Provide for each type of product indicated. Include thermal conductivity, water-vapor permeance thickness, and jackets (both factory- and field-applied if any). 1.2 QUALITY ASSURANCE A. Installer Qualifications: Skilled mechanics who have successfully completed an apprenticeship program or another craft training program certified by the Department of Labor, Bureau of Apprenticeship and Training. PART 2 PRODUCTS 2.1 INSULATION THICKNESS AND TYPES A. All supply and return ductwork in non-conditioned spaces shall be insulated as follows: 1. Exposed Ductwork: 1.5-inches rigid fiberglass board, 3.0 pounds per cubic foot density, to a minimum R-value of 5, complete with a factory applied reinforced aluminum foil vapor barrier, suitably anchored and sealed at all points. 2. Concealed Ductwork: 1.5-inches fiberglass blanket, 0.75 pounds per cubic foot density, to a minimum R-value of 5, complete with a factory applied vapor barrier, suitably anchored and sealed at all points B. The use of flexible elastomeric insulation on ductwork is permitted as an acceptable alternative to fiberglass. Insulation shall be adhered to 100% of the duct surface area. C. Preferred Manuafacturers 1. Johns Manville 2. Knauf 3. Owens Corning 4. Armacell, LLC 2.2 ADHESIVES A. Materials shall be compatible with insulation materials, jackets, and substrates and for bonding insulation to itself and to surfaces to be insulated unless otherwise indicated. B. Flexible Elastomeric Adhesive: Comply with MIL-A-24179A, Type II, Class I. BEARDSLEY DESIGN ASSOCIATES CORNELL – NCP DUCT INSULATION STANDARD SPECIFICATIONS 23 07 13 –PAGE 2 OF 7 MARCH 29, 2013 1. For indoor applications, use adhesive that has a VOC content of 50 g/L or less when calculated according to 40 CFR 59, Subpart D (EPA Method 24). 2. Use adhesive that complies with the testing and product requirements of the California Department of Health Services' "Standard Practice for the Testing of Volatile Organic Emissions from Various Sources Using Small- Scale Environmental Chambers," including 2004 Addenda. C. Mineral-Fiber Adhesive: Comply with MIL-A-3316C, Class 2, Grade A. 1. For indoor applications, use adhesive that has a VOC content of 80 g/L or less when calculated according to 40 CFR 59, Subpart D (EPA Method 24). 2. Use adhesive that complies with the testing and product requirements of the California Department of Health Services' "Standard Practice for the Testing of Volatile Organic Emissions from Various Sources Using Small- Scale Environmental Chambers," including 2004 Addenda. D. ASJ Adhesive, and FSK Jacket Adhesive: Comply with MIL-A-3316C, Class 2, Grade A for bonding insulation jacket lap seams and joints. 1. For indoor applications, use adhesive that has a VOC content of 50 g/L or less when calculated according to 40 CFR 59, Subpart D (EPA Method 24). 2. Use adhesive that complies with the testing and product requirements of the California Department of Health Services' "Standard Practice for the Testing of Volatile Organic Emissions from Various Sources Using Small- Scale Environmental Chambers," including 2004 Addenda. 2.3 MASTICS A. Materials shall be compatible with insulation materials, jackets, and substrates; comply with MIL-PRF-19565C, Type II. 1. For indoor applications, use mastics that have a VOC content of 50 g/L or less when calculated according to 40 CFR 59, Subpart D (EPA Method 24). B. Vapor-Barrier Mastic: Water based; suitable for indoor use on below ambient services. 1. Water-Vapor Permeance: ASTM E 96/E 96M, Procedure B, 0.013 perm (0.009 metric perm) at 43-mil (1.09-mm) dry film thickness. 2. Service Temperature Range: Minus 20 to plus 180 deg F (Minus 29 to plus 82 deg C). 3. Solids Content: ASTM D 1644, 58 percent by volume and 70 percent by weight. 4. Color: White. 2.4 TAPES A. FSK Tape: Foil-face, vapor-retarder tape matching factory-applied jacket with acrylic adhesive; complying with ASTM C 1136. 1. Width: 3 inches (75 mm). 2. Thickness: 6.5 mils (0.16 mm). BEARDSLEY DESIGN ASSOCIATES CORNELL – NCP DUCT INSULATION STANDARD SPECIFICATIONS 23 07 13 –PAGE 3 OF 7 MARCH 29, 2013 3. Adhesion: 90 ounces force/inch (1.0 N/mm) in width. 4. Elongation: 2 percent. 5. Tensile Strength: 40 lbf/inch (7.2 N/mm) in width. 6. FSK Tape Disks and Squares: Precut disks or squares of FSK tape. 2.5 SECUREMENTS A. Insulation Pins and Hangers: 1. Cupped-Head, Capacitor-Discharge-Weld Pins: Copper- or zinc-coated steel pin, fully annealed for capacitor-discharge welding, 0.106-inch- (2.6- mm-) diameter shank, length to suit depth of insulation indicated with integral 1-1/2-inch (38-mm) galvanized carbon-steel washer. 2. Metal, Adhesively Attached, Perforated-Base Insulation Hangers: Baseplate welded to projecting spindle that is capable of holding insulation, of thickness indicated, securely in position indicated when self- locking washer is in place. Comply with the following requirements: a. Baseplate: Perforated, galvanized carbon-steel sheet, 0.030 inch (0.76 mm) thick by 2 inches (50 mm) square. b. Spindle: Copper- or zinc-coated, low-carbon steel, fully annealed, 0.106-inch- (2.6-mm-) diameter shank, length to suit depth of insulation indicated. c. Adhesive: Recommended by hanger manufacturer. Product with demonstrated capability to bond insulation hanger securely to substrates indicated without damaging insulation, hangers, and substrates. 3. Insulation-Retaining Washers: Self-locking washers formed from 0.016- inch- (0.41-mm-) thick, galvanized-steel sheet, with beveled edge sized as required to hold insulation securely in place but not less than 1-1/2 inches (38 mm) in diameter. a. Protect ends with capped self-locking washers incorporating a spring steel insert to ensure permanent retention of cap in exposed locations. B. Staples: Outward-clinching insulation staples, nominal 3/4-inch- (19-mm-) wide, stainless steel or Monel. PART 3 EXECUTION 3.1 GENERAL INSTALLATION REQUIREMENTS A. Install insulation materials, accessories, and finishes with smooth, straight, and even surfaces; free of voids throughout the length of ducts and fittings. B. Install accessories compatible with insulation materials and suitable for the service. Install accessories that do not corrode, soften, or otherwise attack insulation or jacket in either wet or dry state. C. Install insulation with longitudinal seams at top and bottom of horizontal runs. BEARDSLEY DESIGN ASSOCIATES CORNELL – NCP DUCT INSULATION STANDARD SPECIFICATIONS 23 07 13 –PAGE 4 OF 7 MARCH 29, 2013 D. Install multiple layers of insulation with longitudinal and end seams staggered. E. Keep insulation materials dry during application and finishing. F. Install insulation with tight longitudinal seams and end joints. Bond seams and joints with adhesive recommended by insulation material manufacturer. G. Install insulation with least number of joints practical. H. Where vapor barrier is indicated, seal joints, seams, and penetrations in insulation at hangers, supports, anchors, and other projections with vapor- barrier mastic. 1. Install insulation continuously through hangers and around anchor attachments. 2. For insulation application where vapor barriers are indicated, extend insulation on anchor legs from point of attachment to supported item to point of attachment to structure. Taper and seal ends at attachment to structure with vapor-barrier mastic. 3. Install insert materials and install insulation to tightly join the insert. Seal insulation to insulation inserts with adhesive or sealing compound recommended by insulation material manufacturer. I. Apply adhesives, mastics, and sealants at manufacturer's recommended coverage rate and wet and dry film thicknesses. J. Install insulation with factory-applied jackets as follows: 1. Draw jacket tight and smooth. 2. Cover circumferential joints with 3-inch- (75-mm-) wide strips, of same material as insulation jacket. Secure strips with adhesive and outward clinching staples along both edges of strip, spaced 4 inches (100 mm) o.c. 3. Overlap jacket longitudinal seams at least 1-1/2 inches (38 mm). Clean and dry surface to receive self-sealing lap. Staple laps with outward clinching staples along edge at 2 inches (50 mm) o.c. a. For below ambient services, apply vapor-barrier mastic over staples. 4. Cover joints and seams with tape, according to insulation material manufacturer's written instructions, to maintain vapor seal. 5. Where vapor barriers are indicated, apply vapor-barrier mastic on seams and joints and at ends adjacent to duct flanges and fittings. K. Cut insulation in a manner to avoid compressing insulation more than 75 percent of its nominal thickness. L. Finish installation with systems at operating conditions. Repair joint separations and cracking due to thermal movement. M. Repair damaged insulation facings by applying same facing material over damaged areas. Extend patches at least 4 inches (100 mm) beyond damaged areas. Adhere, staple, and seal patches similar to butt joints. BEARDSLEY DESIGN ASSOCIATES CORNELL – NCP DUCT INSULATION STANDARD SPECIFICATIONS 23 07 13 –PAGE 5 OF 7 MARCH 29, 2013 3.2 INSTALLATION OF MINERAL-FIBER INSULATION A. Blanket Insulation Installation on Ducts and Plenums: Secure with adhesive and insulation pins. 1. Apply adhesives according to manufacturer's recommended coverage rates per unit area, for 100 percent coverage of duct and plenum surfaces. 2. Apply adhesive to entire circumference of ducts and to all surfaces of fittings and transitions. 3. Install cupped-head, capacitor-discharge-weld pins on sides and bottom of horizontal ducts and sides of vertical ducts as follows: a. On duct sides with dimensions 18 inches (450 mm) and smaller, place pins along longitudinal centerline of duct. Space 3 inches (75 mm) maximum from insulation end joints, and 16 inches (400 mm) o.c. b. On duct sides with dimensions larger than 18 inches (450 mm), place pins 16 inches (400 mm) o.c. each way, and 3 inches (75 mm) maximum from insulation joints. Install additional pins to hold insulation tightly against surface at cross bracing. c. Pins may be omitted from top surface of horizontal, rectangular ducts and plenums. d. Do not overcompress insulation during installation. e. Impale insulation over pins and attach speed washers. f. Cut excess portion of pins extending beyond speed washers or bend parallel with insulation surface. Cover exposed pins and washers with tape matching insulation facing. 4. For ducts and plenums with surface temperatures below ambient, install a continuous unbroken vapor barrier. Create a facing lap for longitudinal seams and end joints with insulation by removing 2 inches (50 mm) from one edge and one end of insulation segment. Secure laps to adjacent insulation section with 1/2-inch (13-mm) outward-clinching staples, 1 inch (25 mm) o.c. Install vapor barrier consisting of factory- or field-applied jacket, adhesive, vapor-barrier mastic, and sealant at joints, seams, and protrusions. a. Repair punctures, tears, and penetrations with tape or mastic to maintain vapor-barrier seal. b. Install vapor stops for ductwork and plenums operating below 50 deg F (10 deg C) at 18-foot (5.5-m) intervals. Vapor stops shall consist of vapor-barrier mastic applied in a Z-shaped pattern over insulation face, along butt end of insulation, and over the surface. Cover insulation face and surface to be insulated a width equal to two times the insulation thickness, but not less than 3 inches (75 mm). 5. Overlap unfaced blankets a minimum of 2 inches (50 mm) on longitudinal seams and end joints. At end joints, secure with steel bands spaced a maximum of 18 inches (450 mm) o.c. 6. Install insulation on rectangular duct elbows and transitions with a full insulation section for each surface. Install insulation on round and flat- oval duct elbows with individually mitered gores cut to fit the elbow. 7. Insulate duct stiffeners, hangers, and flanges that protrude beyond insulation surface with 6-inch- (150-mm-) wide strips of same material BEARDSLEY DESIGN ASSOCIATES CORNELL – NCP DUCT INSULATION STANDARD SPECIFICATIONS 23 07 13 –PAGE 6 OF 7 MARCH 29, 2013 used to insulate duct. Secure on alternating sides of stiffener, hanger, and flange with pins spaced 6 inches (150 mm) o.c. B. Board Insulation Installation on Ducts and Plenums: Secure with adhesive and insulation pins. 1. Apply adhesives according to manufacturer's recommended coverage rates per unit area, for 100 percent coverage of duct and plenum surfaces. 2. Apply adhesive to entire circumference of ducts and to all surfaces of fittings and transitions. 3. Install either capacitor-discharge-weld pins and speed washers or cupped- head, capacitor-discharge-weld pins on sides and bottom of horizontal ducts and sides of vertical ducts as follows: a. On duct sides with dimensions 18 inches (450 mm) and smaller, place pins along longitudinal centerline of duct. Space 3 inches (75 mm) maximum from insulation end joints, and 16 inches (400 mm) o.c. b. On duct sides with dimensions larger than 18 inches (450 mm), space pins 16 inches (400 mm) o.c. each way, and 3 inches (75 mm) maximum from insulation joints. Install additional pins to hold insulation tightly against surface at cross bracing. c. Pins may be omitted from top surface of horizontal, rectangular ducts and plenums. d. Do not overcompress insulation during installation. e. Cut excess portion of pins extending beyond speed washers or bend parallel with insulation surface. Cover exposed pins and washers with tape matching insulation facing. 4. For ducts and plenums with surface temperatures below ambient, install a continuous unbroken vapor barrier. Create a facing lap for longitudinal seams and end joints with insulation by removing 2 inches (50 mm) from one edge and one end of insulation segment. Secure laps to adjacent insulation section with 1/2-inch (13-mm) outward-clinching staples, 1 inch (25 mm) o.c. Install vapor barrier consisting of factory- or field-applied jacket, adhesive, vapor-barrier mastic, and sealant at joints, seams, and protrusions. a. Repair punctures, tears, and penetrations with tape or mastic to maintain vapor-barrier seal. b. Install vapor stops for ductwork and plenums operating below 50 deg F (10 deg C) at 18-foot (5.5-m) intervals. Vapor stops shall consist of vapor-barrier mastic applied in a Z-shaped pattern over insulation face, along butt end of insulation, and over the surface. Cover insulation face and surface to be insulated a width equal to two times the insulation thickness, but not less than 3 inches (75 mm). 5. Install insulation on rectangular duct elbows and transitions with a full insulation section for each surface. Groove and score insulation to fit as closely as possible to outside and inside radius of elbows. Install insulation on round and flat-oval duct elbows with individually mitered gores cut to fit the elbow. BEARDSLEY DESIGN ASSOCIATES CORNELL – NCP DUCT INSULATION STANDARD SPECIFICATIONS 23 07 13 –PAGE 7 OF 7 MARCH 29, 2013 6. Insulate duct stiffeners, hangers, and flanges that protrude beyond insulation surface with 6-inch- (150-mm-) wide strips of same material used to insulate duct. Secure on alternating sides of stiffener, hanger, and flange with pins spaced 6 inches (150 mm) o.c. END OF SECTION 230713