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OC Sportsplex Pool HVAC Unit Replacement <br />PDC Project 23022 HVAC Ducts and Casings 23 31 00 - 4 <br />H.Unless drawings indicate the required framing,provide angle iron framing around roof opening <br />where duct penetrates through roof decking,to maintain roof decking structural integrity in <br />accordance with roof decking manufacturer's recommendations. This is not required for concrete <br />decking. For concrete decking,consult with Structural Engineer for location and size of opening <br />prior to execution of Work. <br />I.For welded ducts,soldered ducts or ducts with water tight joints,do not use supports utilizing <br />screws or other penetrations into ductwork. <br />J.All hangers and supports shall be fully galvanized. <br />2.05 MANUFACTURED DUCTWORK AND FITTINGS <br />A.Double Wall Insulated Round Ducts: Round spiral lockseam duct with galvanized steel outer wall, <br />perforated aluminum inner wall;fitting with solid inner wall. <br />1.Manufacture in accordance with SMACNA (DCS). <br />2.Insulation: <br />a.Thickness: 1 inch. <br />b.Material: Fiberglass or elastomeric foam. <br />c.Finish:"Paint grip"galvanneal or mill phosphatized <br />3.Manufacturers: <br />a.MKT Metal Manufacturing​​ <br />b.Hamlin <br />c.SMC <br />d.McGill Airflow <br />e.Or Approved Equal <br />B.Double Wall Insulated Rectangular Ducts: Rectangular spiral lockseam duct with galvanized steel <br />outer wall,perforated aluminum inner wall;fitting with solid inner wall. <br />1.Manufacture in accordance with SMACNA (DCS). <br />2.Insulation: <br />a.Thickness: 1 inch. <br />b.Material:Fiberglass or elastomeric foam. <br />c.Finish:"Paint grip"galvanneal or mill phosphatized <br />2.06 LONGITUDINAL SEAM: <br />A.Rectangular Duct: <br />1.Unless otherwise indicated,use Pittsburgh lock seam construction. <br />2.Seal longitudinal seams with approved sealant or provide pre-sealed from factory with <br />encapsulated mastic. <br />3.Button punch snap lock construction (SMACNA L-2)is not allowed except for ductwork that is <br />both low pressure (2”WG or lower pressure class)and 18”and smaller duct width. <br />4.Button punch snap lock construction is not allowed for ductwork in chases and areas above <br />inaccessible ceilings. <br />5.Button punch snaplock construction is not allowed on exhaust ductwork or aluminum <br />ductwork <br />B.Round and Oval Duct <br />1.Unless otherwise indicated,longitudinal seams shall be in accordance with SMACNA HVAC <br />Duct Construction Standards with the following exceptions: <br />a.Snaplock seams are not allowed. <br />b.SMACNA seam types RL-3,6A,6B,7,and 8 shown in Figure 3-2 are not allowed, <br />except for 2"w.g.class round ducts 16"or less in diameter. <br />2.07 RECTANGULAR TRANSVERSE JOINT CONNECTORS: <br />A.Slide-on Transverse Joint Connectors: <br />1.Duct constructed using engineered slide-on connector systems must be submitted and <br />conform to manufacturer’s published duct construction standards and guidelines for joint <br />classification,sheet metal gauge,intermediate and joint reinforcement size and spacing, <br />Docusign Envelope ID: D4F3B98E-0756-4A0C-A3AD-05AA32D39F1C