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DocuSign Envelope ID: 9826C043- 4C32- 49CD- A4CC- DC28ABAB7CE7 <br />SECTION 238100 - HVAC INSULATION <br />rigid polyisocyan u rate may be substituted for calcium silicate provided insert and shield length and <br />shield gauge are increased to compensate for lower insulation compressive strength. <br />D. Precompressed 20# density molded fiberglass blocks, Hamfab or equal, of the same thickness as <br />adjacent insulation may be substituted for calcium silicate inserts with one 1 "x6" block for piping <br />through 2 -1/2" and three 1 "x6" blocks for piping through 4 ". Submit shield schedule to demonstrate <br />equivalency to preeng ineered/preman ufactu red product described above. <br />E. Wood blocks will not be accepted. <br />2.19 ACCESSORIES <br />A. All products shall be compatible with surfaces and materials on which they are applied, and be <br />suitable for use at operating temperatures of the systems to which they are applied. <br />B. Adhesives, sealants, and protective finishes shall be as recommended by insulation manufacturer for <br />applications specified. <br />C. Insulation bands to be 3/4 inch wide, constructed of aluminum or stainless steel. Minimum thickness <br />to be .015 inch for aluminum and .010 inch for stainless steel. <br />D. Tack fasteners to be stainless steel ring grooved shank tacks. <br />E. Staples to be clinch style. <br />F. Insulating cement to be ANSI /ASTM C195, hydraulic setting mineral wool. <br />G. Finishing cement to be ASTM C449. <br />H. Fibrous glass or canvas fabric reinforcing shall have a minimum untreated weight of 6 oz. /sq. yd. <br />I. Bedding compounds to be non- shrinking and permanently flexible. <br />J. Vapor barrier coatings and tapes to have maximum applied water vapor permeance of .05 perms. <br />K. Fungicidal water base coating (Foster 40 -20 or equal) to be compatible with vapor barrier coating. <br />PART 3 - EXECUTION <br />3.1 INSTALLATION <br />A. Install insulation, jackets and accessories in accordance with manufacturers instructions and under <br />ambient temperatures and conditions recommended by manufacturer. Surfaces to be insulated must <br />be clean and dry. <br />B. Do not insulate systems or equipment which are specified to be pressure tested or inspected, until <br />testing, inspection and any necessary repairs have been successfully completed. <br />C. Install insulation with smooth and even surfaces. Poorly fitted joints or use of filler in voids will not be <br />accepted. Provide neatly beveled and coated terminations at all nameplates, uninsulated fittings, or <br />at other locations where insulation terminates. <br />D. Install fabric reinforcing without wrinkles. Overlap seams a minimum of 2 inches. <br />E. Use full length material (as delivered from manufacturer) wherever possible. Scrap piecing of <br />insulation or pieces cut undersize and stretched to fit will not be accepted. <br />F. Insulation shall be continuous through sleeves and openings except where fire rated penetration <br />materials require interruption of insulation. Vapor barriers shall be maintained continuous through all <br />penetrations. <br />G. Provide a complete vapor barrier for insulation on the following systems: <br />1. Insulated Duct <br />2. Equipment or piping with a surface temperature below 65 degrees F <br />3.2 PIPE INSULATION: <br />A. General: <br />1. Install insulation with butt joints and longitudinal seams closed tightly. Provide minimum 2" lap <br />on jacket seams and 2" tape on butt joints, firmly cemented with lap adhesive. Additionally <br />secure with staples along seams and butt joints. Coat staples, longitudinal and transverse <br />seams with vapor barrier mastic on systems requiring vapor barrier. <br />2. Install insulation continuous through pipe hangers and supports with hangers and supports on <br />the exterior of insulation. Where a vapor barrier is not required or where roller hangers are not <br />being used, hangers and supports may be attached directly to piping with insulation <br />completely covering hanger or support and jacket sealed at support rod penetration. Where <br />riser clamps are required to be attached directly to piping requiring vapor barrier, extend <br />insulation and vapor barrier jacketing /coating around riser clamp. <br />3. Fully insulate all reheat coil piping, fittings and valves (with the exeption of unions) up to coil <br />connection to prevent condensation when coil is inactive during cooling season. <br />B. Insulation Inserts and Pipe Shields: Provide insulation inserts and pipe shields at all hanger and <br />support locations. Inserts may be omitted on 3/4" and smaller copper piping provided 12" long 22 <br />gauge pipe shields are used. <br />C. Fittings and Valves: Fittings, valves, unions, flanges, couplings and specialties may be insulated with <br />factory molded or built up insulation of the same thickness as adjoining insulation. Cover insulation <br />with fabric reinforcing and mastic or where temperatures do not exceed 150 degrees, PVC fitting <br />covers. Secure PVC fitting covers with tack fasteners and 1 -1/2" band of mastic over ends, throat, <br />seams and penetrations. On systems requiring vapor barrier, use vapor barrier mastic. <br />D. Mineral Fiber: Secure each 3' section with three stainless steel bands or five 16 gauge stainless <br />steel or annealed copper tie wires evenly spaced and at ends. Twist wire ends, snip off excess and <br />turn ends over into insulation. Stagger joints where more than one layer is used. <br />E. Elastomeric and Polyolefin: Where practical, slip insulation on piping during pipe installation when <br />pipe ends are open. Miter cut fittings allowing sufficient length to prevent stretching. Completely seal <br />Reece, Noland & McElrath, Inc. 238100-3 Orange County Board of Elections <br />Orange Co., NC 05/04/18 <br />