SECTION 15562
HVAC DUCTWORK INSULATION
PART 1 - GENERAL
1.1 SUMMARY
A. Ductwork insulation.
B. Insulation jackets.
1.2 REFERENCES AND RELATED DOCUMENTS
A. National Fire Protection Association (NFPA):
1. NFPA 255 Building Materials, Test of Surface Burning Characteristics (ASTM E84).
B. American Society for Testing and Materials (ASTM):
1. ASTM C612 Specification for Mineral Fiber Block and Board Thermal Insulation.
C. Underwriters Laboratories (UL):
1. UL 723 Test for Surface Burning Characteristics of Building Materials
D. Drawings and general provisions of contract, including General and Supplementary Conditions and Division 1 specification sections, apply to this section.
E. MICA: National Commercial and Industrial Insulation Standards (Latest Edition).
1.3 SUBMITTALS
A. General
1. Submit the following in accordance with Conditions of Contract and Division 1 specification sections.
B. Product data for each type of ductwork insulation identifying k value, thickness, and accessories.
C. Material certificates, signed by the manufacturer, certifying that materials comply with specified requirements where laboratory test reports cannot be obtained.
D. Material test reports prepared by a qualified independent testing laboratory. Certify insulation meets specified requirements.
1.4 QUALITY ASSURANCE
A. Materials
1. Flame/Smoke Ratings: Provide composite insulation (insulation, jackets, coverings, sealers, mastics, and adhesives) with flamespread index of 25 or less, and smoke developed index of 50 or less as tested according to ASTM E84, NFPA 255 or by Underwriters Laboratories or other testing or inspection organization acceptable to the authority having jurisdiction. Label insulation with appropriate markings of testing laboratory
1.5 SCHEDULING AND SEQUENCING
A. Schedule insulation application after testing of duct systems.
PART 2 - PRODUCTS
2.1 MANUFACTURERS
A. Manufacturers: Subject to compliance with requirements, provide products by one of the following:
1. Glass Fiber:
a. Knauf Fiber Glass
b. Manville
c. Owens Corning Fiberglass Corporation
2.2 MATERIALS
A. Type A: Flexible Glass Fiber
1. ASTM C553 Type 1; "k" value of 0.29 at 75 ?F; foil scrim
perm rating.
B. Type B: Board
1. ASTM C 612, Class 2, semi-rigid jacketed board "k" value of 0.23 @ 75?F; FSK facing with 0.02 perm rating.
C. Adhesives
1. Waterproof fire-retardant type produced under the UL classification and follow- up service.
D. Lagging Adhesive
1. Fire resistive to NFPA 255 or UL 723.
E. Impale Anchors
1. Galvanized steel, 12 gage, self-adhesive pad.
F. Joint Tape
1. Glass fiber cloth, FSK backing.
G. Insulation Bands
1. ¾" wide, constructed of aluminum or stainless steel. Minimum thickness to be
0.15 inch for aluminum and .010 inch for stainless steel.
H. Tie Wire
1. Stainless steel, 16 gage.
I. Vapor Barrier Coating
1. Waterproof coating recommended by insulation manufacturer for outside service.
2.3 JACKETS
A. General
1. ASTM C 1136, except as otherwise indicated.
PART 3 - EXECUTION
3.1 PREPARATION
A. Surface Preparation
1. Clean, dry, and remove foreign materials such as rust, scale, and dirt.
B. Mix insulating cements with clean potable water. Mix insulating cements contacting stainless steel surfaces with demineralized water.
3.2 INSTALLATION
A. Refer to schedules at the end of this section for materials, forms, jackets, and thicknesses required for each ductwork system.
B. Select accessories compatible with materials suitable for the service. Select accessories that do not corrode, soften, or otherwise attack the insulation or jacket in either the wet or dry state.
C. Install vapor barriers on insulated ducts having surface operating temperatures below 60°F.
D. Install insulation, accessories and finishes in accordance with the latest edition of MCIA National Commercial and Industrial Insulation Standards and manufacturer's
installation instructions. Exceptions to these standards will be accepted where specifically modified in these specifications or where prior written approval has been obtained from the Engineer.
E. Install insulation with smooth, straight, and even surfaces.
F. Seal joints and seams to maintain vapor barrier on insulation requiring a vapor barrier.
G. Seal penetrations for hangers, supports, anchors, and other projections in insulation requiring a vapor barrier.
H. Seal Ends
1. Except for flexible elastomeric insulation, taper ends at 45 deg angle and seal with lagging adhesive. Cut ends of flexible elastomeric cellular insulation square and seal with adhesive.
I. Apply adhesives and coatings at manufacturer's recommended coverage per gallon rate.
J. Keep insulation materials dry during application and finishing.
K. Items Not Insulated: Unless otherwise indicated do not apply insulation to the following systems, materials, and equipment:
1. Fibrous glass ducts.
2. Factory insulated flexible ducts.
3. Factory insulated plenums, casings, terminal boxes, and filter boxes and sections.
4. Flexible connectors.
5. Vibration control devices.
6. Testing laboratory labels and stamps.
7. Access panels and doors in air distribution systems.
L. Install block and board insulation as follows:
1. Speed Washers Attachment: Secure insulation tight and smooth with speed washers and welded pins. Space anchor pins 18 inches apart each way and 3 inches from insulation joints. Apply vapor barrier tape to seal insulation in contact, open joints, breaks, punctures, and voids in insulation.
M. Blanket Insulation: Install tight and smooth. Secure to ducts having long sides or diameters as follows:
1. Smaller Than 24 Inches: Bonding adhesive applied in 6-inch wide transverse strips on 12-inch centers.
2. 24 Inches and Larger: Anchor pins spaced 12 inches apart each way. Apply bonding adhesive to prevent sagging of the insulation.
3. Overlap joints 3 inches.
4. Seal joints, breaks, and punctures with vapor barrier tape.
N. At test plugs, provide removable insulation plugs.
O. Insulate around damper operators so as to maintain full operating range of operator.
3.3 JACKETS
A. Foil and Paper Jackets (FSK)
1. Install jackets drawn tight. Install lap or butt strips at joints with material same as jacket. Secure with adhesive. Install jackets with 1 1/2 inch laps at longitudinal joints and 3-inch wide butt strips at end joints.
2. Seal openings, punctures, and breaks in vapor barrier jackets and exposed insulation with vapor barrier compound.
B. Install metal jacket with 2 inch overlap at longitudinal and butt joints. Overlap longitudinal joints to shed water. Seal butt joints with weatherproof sealant recommended by insulation manufacturer. Secure jacket with stainless steel draw bands 12 inches on center and at butt joints.
3.4 SCHEDULE
A. Unless otherwise indicated, insulate the following duct systems:
Field Applied Jacket
*Allow for maintenance access via duct access doors.
**Utilize factory FSK (foil-scrim-kraft) jackets
END OF SECTION
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