Orange County NC Website
Browse       Search
DocuSign Envelope ID: B94F2D40-3B3C-47A7-86C2-6F1 B4F92C62C <br /> SECTION 07 92 00 -ELASTOMERIC JOINT SEALANTS <br /> 2. Color: Match silicone seal. <br /> PART 3 -EXECUTION <br /> 3.1 EXAMINATION <br /> A. Contractor shall inspect joints and substrate for soundness and notify Engineer in writing of any unacceptable <br /> conditions. <br /> B. Commencement of work signifies Contractor's acceptance of substrate. Any defects in sealant work resulting from <br /> such accepted substrates shall be corrected by the Contractor at no additional expense to the Owner. <br /> 3.2 PREPARATION <br /> A. General <br /> 1. Contractor shall follow all of the applicable preparation requirements published by the Manufacturer. <br /> 2. Substrate shall be dry and cleaned free of loose debris and foreign matter prior to installation of materials. <br /> 3. Contractor shall inspect substrate for unacceptable conditions, and inspect the environment for materials <br /> incompatible with silicone sealant. <br /> 4. Contractor shall dig-out or grind-out, and remove all old sealants and loose materials in joint. Contractor shall <br /> not re-seal over existing sealant. <br /> 5. Prime masonry substrates.Contractor shall apply primer to substrates where required for adhesion.Avoid primer <br /> contact with bond-breaker materials. Refer to Manufacturer's published literature for substrates commonly <br /> requiring primer. When condition of substrate is suspect,Contractor shall apply Manufacturer's primer to ensure <br /> proper adhesion. <br /> 6. Apply backer-rod in open joints to prevent 3-sided adhesion. Backer-rod shall be sized per Manufacturer's <br /> published literature. Closed cell backer-rod shall not be punctured during installation to prevent out-gassing that <br /> may result in bubbling/blistering in sealant. <br /> 7. Where shallow joints cannot accept backer-rod, Contractor shall install polyethylene strip or tape to prevent 3- <br /> sided adhesion at back of the joint. <br /> B. Protection <br /> 1. Protect building surfaces and interior with canvas or suitable tarp wherever equipment or materials are taken up <br /> to or down from roof. <br /> 2. Protect building interiors using suitable methods against any damage from roofing activities. <br /> 3.3 APPLICATION <br /> A. Joints(masonry joints, routed CMU cracks and other exposed building joints): <br /> 1. Apply polyurethane sealant at joints in the CMU colored band. <br /> 2. Placement Procedure: Prime substrate as required based upon the recommendations of the sealant <br /> Manufacturer, when field testing indicates need, and when the joints may be subject to water immersion after <br /> cure, and as approved by the Engineer. <br /> 3. Install approved backer rod or bond breaker tape in all joints subject to thermal movement to prevent 3-sided <br /> bonding, and to set the depth of the sealant at a maximum of 1/2 in., measured at the center point of the joint <br /> width. <br /> 4. Where aesthetics require, joints shall be masked (taped) to prevent discoloration or application on unwanted <br /> areas, as directed by the Owner and/or Engineer. If masking tape is used, it shall not be removed before tooling, <br /> yet must be removed before the initial cure of the sealant. Do not apply the masking tape until just prior to the <br /> sealant application. <br /> 5. Install sealant into the prepared joints when the joint is at the mid-point of its expansion and contraction cycle. <br /> Place the nozzle of the gun, either hand, air, or electric powered, into the bottom of the joint and fill entire joint. <br /> Keep the tip of the nozzle in the sealant; continue with a steady flow of sealant preceding the nozzle to avoid air <br /> entrapment.Avoid overlapping the sealant to eliminate the entrapment of air. <br /> 6. Contractor shall tool sealant to properly fill the joint. <br /> 7. Application shall be in accordance with the sealant Manufacturer's published requirements and all limitations and <br /> precautions for the silicone sealant shall be followed. <br /> B. Install sealant into the prepared joints at exterior pipes, conduits, louvers or vents penetrating the CMU that are to <br /> remain. <br /> C. Sealing sheet metal coping joints, sheet metal counterflashing joints and sheet metal flashing joints: <br /> 1. Remove any existing exposed sealant and prepare/prime metal substrate as required by the preformed silicone <br /> seal manufacturer. <br /> 2. Apply preformed silicone strip sealant to joints. <br /> D. At the gutter ends adjacent to the CMU walls, apply backing material and sealant between the metal fascia and the <br /> CMU walls. <br /> ©BOOMERANG DESIGN 07 92 00-3 510 Meadowlands Drive,Hillsborough,NC <br /> BD#1835 ORANGE COUNTY, NC 12/07/2018 <br />