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HomeMy WebLinkAbout15891.pdf BICKFORD OF CARMEL, IN 12/12/2012 METAL DUCTWORK 15891-1 SECTION 15891 METAL DUCTWORK PART 1 - GENERAL 1.1 RELATED DOCUMENTS A. Drawings and general provisions of Contract, including General and Supplementary Conditions and Division-1 Specification sections, apply to work of this section. 1.2 COORDINATION A. The Contractor shall coordinate his work with other mechanical, electrical and plumbing systems and field measure, as required, prior to fabrication to facilitate a complete installation. 1.3 SUBMITTALS A. Product Data Submit manufacturer’s product data and catalogue information for each type duct, hanger and sealant etc. to be incorporated into the project. B. Record Drawings At project closeout, submit record drawings of installed metal ductwork and ductwork products. C. Test Reports Submit leak testing reports to the engineer for review upon completion of testing activities required under Part 3 Execution. D. Operating and Maintenance Manuals Submit Operating and Maintenance Manuals in accordance with Specification Section 15010 containing, but not limited too, all information required therein. 1.4 VERIFICATION A. Investigate the existing and proposed structural and finished conditions affecting the ductwork, and arrange the equipment accordingly, furnishing required fittings, offsets, and accessories. Route ductwork to avoid interference with other mechanical, electrical and plumbing systems. Consult with the Engineer before making any changes in the event it becomes necessary to make changes in pipe locations due to the building construction. Any such changes required shall be made without added cost to the Owner. 1.5 QUALITY ASSURANCE A. SMACNA Standards Comply with SMACNA’s “HVAC Duct Construction Standards, Metal and Flexible” for fabrication and installation of metal ductwork. B. ASHRAE Standards Comply with ASHRAE Handbook, Equipment Volume, Chapter 1 “Duct Construction”, for fabrication and installation of metal ductwork. C. NFPA Compliance BICKFORD OF CARMEL, IN 12/12/2012 METAL DUCTWORK 15891-2 Comply with NFPA 90A “Standard for the Installation of Air Conditioning and Ventilating Systems” and NFPA 90B “Standard for the Installation of Warm Air Heating and Air Conditioning Systems”. PART 2 - PRODUCTS 2.1 DUCTWORK MATERIALS A. Except as otherwise indicated, fabricate ductwork from galvanized sheet steel complying with ASTM A 527, lock-forming quality; with G 90 zinc coating in accordance with ASTM A 525; and mill phosphatized for exposed locations. 2.2 MISCELLANEOUS DUCTWORK MATERIALS A. Provide miscellaneous materials and products of types and sizes indicated and, where not otherwise indicated, provide type and size required to comply with ductwork system requirements including proper connection of ductwork and equipment. Provide fittings as detailed on the drawings and as detailed in SMACNA HVAC Duct Construction Standards. 1. Radius Elbows and Square Throat Elbows: Details on Drawings. 2. Reducing Transition Fittings: Details on Drawings. 3. Off-Sets and Transitions: Reference SMACNA Fig. 2-9. 4. Off-Sets Around Obstructions: Reference SMACNA Fig. 2-10, Figures B, C & E. 5. Access Doors: Provide as necessary to allow for proper maintenance and inspection. Reference SMACNA Fig. 2-12. 6. Turning Vanes: Single vane type, SMACNA Fig. 2-3. Double vane used in all supply air. 7. Rectangular to Rectangular Take-Off Fittings: Provide as indicated on the drawings. 8. Fittings: Provide as indicated on the drawings. Utilize rectangular widths equal to 1.5 times the duct dia. and rectangular depth equal to 1.0 times the duct dia. Fittings shall be 22 gauge shop fabricated with transitions not less than four inches long. 9. Volume Dampers: Provide as indicated on the drawings, reference SMACNA Figs. 2-14 and 2-15. 10. Duct Sealant: Non-hardening, non-migrating mastic or liquid elastic sealant, type applicable for fabrication/installation detail, as compounded and recommended by manufacturer specifically for sealing joints and seams in ductwork. 11. Ductwork Support Materials: Except as otherwise indicated, provide hot-dipped galvanized steel fasteners, anchors, rods, straps, trim and angles for support of ductwork. BICKFORD OF CARMEL, IN 12/12/2012 METAL DUCTWORK 15891-3 2.3 FABRICATION A. Shop fabricate ductwork of gages and reinforcement complying with SMACNA “HVAC Duct Construction Standards” as follows: SYSTEM CLASSIFICATION Exhaust air ductwork Table 1-5, 2” W.G. B. Fabricate ductwork with duct liner in each section of duct where specified. Laminate liner to internal surfaces of duct in accordance with instructions by manufacturers of lining and adhesive, and fasten with mechanical fasteners. C. Supply air ductwork shall be fabricated from 24-gage sheet steel minimum. 2.4 FACTORY-FABRICATED LOW PRESSURE DUCTWORK A. Subject to compliance with requirements, provide factory-fabricated ductwork of one of the following: Semco Mfg., Inc., United Sheet Metal Div., United McGill Corp. 2.5 ROUND DUCTWORK – LOW VELOCITY A. Construct of galvanized sheet steel complying with ASTM A 527 by the following methods and in minimum gages listed. Diameter Minimum Gage Method of Manufacture 6” to 26” 24 Longitudinal Seam for Concealed Round Ductwork 10” to 36” 22 Spiral Lockseam for Exposed Round Ductwork B. Fittings and Couplings Construct of fittings and couplings of minimum gages listed. Provide continuous welds along seams. Diameter Minimum Gage 6” to 36” 20 PART 3 - EXECUTION 3.1 INSTALLATION OF METAL DUCTWORK A. Assemble and install ductwork in accordance with recognized industry practices. Locate ductwork runs, except as otherwise indicated, vertically and horizontally and avoid diagonal runs wherever possible. Locate runs as indicted by diagrams, details and notations or, if not otherwise indicated, run ductwork in shortest route which does not obstruct useable space or block access for servicing building and its equipment. Hold ducts close to walls, overhead construction, columns, and other structural and permanent enclosure elements of building. Limit clearance to ½” where furring is shown for enclosure or concealment of ducts, but allow for insulation thickness, if any. Where possible, locate insulated ductwork for 1” clearance outside of insulation. Wherever possible in finished and occupied spaces, conceal ductwork from view, by locating in mechanical shafts, hollow wall construction or above suspended ceilings. Coordinate layout with suspended ceiling and lighting layouts and similar finished work. BICKFORD OF CARMEL, IN 12/12/2012 METAL DUCTWORK 15891-4 1. Penetrations Where ducts pass through interior partitions and exterior walls, and are exposed to view, conceal space between construction opening and duct or duct insulation with sheet metal flanges of same gage as duct. Overlap opening on 4 sides by at least 1-1/2”. Fasten to duct and substrate. 2. Fire and Smoke Barrier Penetrations Where ductwork passes through fire and smoke rated walls, partitions, ceilings or floors, the rated integrity shall be maintained. Refer to Section 15055 “Basic Piping Materials and Methods” for special sealers and materials. 3. Installation Install metal ductwork in accordance with SMACNA HVAC Duct Construction Standards. 24 gage minimum. 3.2 EQUIPMENT CONNECTIONS A. Connect metal ductwork to equipment as indicated, provide flexible connection for each ductwork connection to equipment mounted on vibration isolators, and/or equipment containing rotating machinery. Provide access doors as required. END OF SECTION