Specification:Joint sealer properties and application

__NUMBEREDHEADINGS__ =GENERAL=

DESCRIPTION
 This specification provides guidance for identifying joint sealer properties and appropriate applications. This specification has been developed for use on historic properties (defined as any district, site, building, structure, or object that is listed in or eligible for listing in the National Register of Historic Places) and provides an overview of accepted practices. Site-specific specifications will be provided by the Architect when appropriate. All work described herein and related work must conform to the Secretary of Interior’s Standards for the Treatment of Historic Properties. The Contractor shall provide all labor, materials, equipment, and operations required to complete the rehabilitation work indicated herein. All work described herein and related work must have the approval of a Cultural Resources Manager, Conservator, Historic Architect, or other professional who meets the standards outlined in the Secretary of the Interior’s Standards – Professional Qualifications Standards pursuant to 36 CFR 61. Such person is referred to in this document as the Architect. 

SECTION INCLUDES
 Furnish and Install Caulking and Sealants 

RELATED SECTIONS
<ol type="A"> Section 03700 – Restoration of Concrete</li> Section 03732 – Composite and Mechanical Concrete Repair</li> Section 04110 – Historic Stucco</li> Section 04211 – Historic Brick</li> Section 04214 – Terra Cotta and Ceramics</li> Section 04500 – Masonry Restoration</li> Section 04720 – Historic Cast Stone</li> Section 06200 – Finish Carpentry</li> Section 06220 – Architectural Woodwork</li> Section 07315 – Slate Roofing</li> Section 07600 – Metal Roofing</li> Section 07631 – Flashing, Gutters and Drains </li> Section 08510 – Metal Window Restoration</li> Section 08610 – Wood Windows</li> Section 09910 – Exterior Paint</li> </ol>

SUBMITTALS
<ol type="A"> Product Literature: Submit manufacturer’s product literature including technical data, application instructions and standard color cards for each type of joint sealant and accessory product required. Product literature shall demonstrate conformance with the physical properties and technical standards referenced herein.</li> <li> Samples: <ol> <li>Submit manufacturer's standard bead samples consisting of strips of actual product, showing full range of colors available for each sealant product exposed to view. Color(s) to be selected by the Architect.</li> <li>Submit a 12-inch long sample of each type of backer rod required.</li> </ol> </li> <li>Submit written certification from sealant manufacturer or manufacturer's representative that, after visiting the site and examining the conditions and locations where sealants are to be installed, the sealant specified is correct for the use intended. If the sealant is not correct for the situation, the manufacturer shall submit in writing to the Architect the recommendation for the correct sealant to be used.</li> </ol>

QUALITY ASSURANCE
<ol type="A"> <li>Work Experience: The Contractor performing the work of this section shall have a minimum of seven years experience in the installation of latex and elastomeric sealants on wood, metal and masonry substrates and shall have successfully completed at least three projects of similar scope within the previous five years. He/she shall demonstrate a working knowledge of The Secretary of the Interior’s Standards for the Treatment of Historic Properties with Guidelines for Preserving, Rehabilitating, Restoring &amp; Reconstructing Historic Buildings.</li> <li>Installer shall provide a written warranty against defects in material and installation for a period of five years.</li> </ol>

MOCK-UPS
<ol type="A"> <li>The Contractor shall prepare two mock-up installations of each type of sealant joint to be installed at locations selected by the Architect. Joint mock-ups shall be a minimum of four feet and not to exceed 10 feet. Mock-ups will be inspected for both color and installation technique.</li> <li>After curing and prior to approval of the test panel, the installer shall test adhesion of the sealant joint by manually trying to pull the sealant from one of the mock-ups of each sealant type. Test shall be performed in the presence of the Architect.</li> <li>The Contractor shall prepare up to three additional mock-ups of each sealant type at no additional cost to the Owner if required to secure approval. Once approved, the remaining mock-up shall remain in place as a standard for evaluating all future work. Once each sealant type is approved, single mock-ups of any additional colors may be required for evaluation of appearance only.</li> </ol>

DELIVERY, STORAGE AND HANDLING
<ol type="A"> <li>Deliver all products in original packaging, unopened, with manufacturer’s name and product identification visible thereon. Store in a protected area within the temperature range recommended by the sealant manufacturer.</li> </ol>

PROJECT / SITE CONDITIONS
<ol type="A"> <li>Sealant installation shall occur only when surface and ambient temperatures are within the range specified by the manufacturer and in accordance with favorable conditions as defined in ASTM C1193. Do not install sealants when moisture or frost is present on the surface.</li> <li>The Contractor shall protect adjacent materials during execution of the work. Excess sealant on adjacent materials must be removed before curing to avoid stains and discoloration.</li> <li>Coordinate sealant installation with the roofing, carpentry, sheet metal, masonry restoration and other trade Contractors as required to minimize disruption of the work.</li> </ol> =PRODUCTS=

ACCEPTABLE MANUFACTURERS
<ol type="A"> <li>Product manufacturers shall be approved by the Architect. </li> </ol>

CAULKING
<ol type="A"> <li>Exterior Caulking: shall be paintable urethane for existing exterior woodwork (ASTM C920, Type S, Grade NS, Class 25) or paintable, exterior grade siliconized acrylic caulk (ASTM C834). Careful consideration must be used in order to avoid trapping moisture under exterior surfaces. For instance, weatherboards shall only be caulked on the vertical, not horizontal gaps.</li> <li>Interior Caulking: Acrylic painter’s caulk; ASTM C834. Interior caulking is only acceptable on surfaces the Architect approves for paint. For instance, caulk is not to be used on plaster or masonry.</li> </ol>

WOOD AND MASONRY SEALANTS:
<ol type="A"> <li>Sealants shall not be used on historic masonry. However, the Architect may allow joint sealants on concrete which utilizes modern mixes. See reports 03700.01-Concrete Properties and 03732.01-Composite and Mechanical Concrete Repair for detailed information on concrete repairs.</li> <li>Exterior Grade Sealant for specified joints in masonry shall be a non-sag, gun grade, single or multi-component urethane sealant complying with ASTM C920, Type M or S, Grade NS, Class 25, use group NT, M, A and O. The Architect shall select color from manufacturer's full range of colors. </li> <li> Exterior Grade Sealant for perimeter of existing wood window and door frames shall be silicone or urethane; ASTM C920-05, Type S, Grade NS, Class 25. Use group M, A or O as applicable. All products and placements must be approved by the Architect. </li> </ol>

TRAFFIC SEALANTS
<ol type="A"> <li>Sealants shall not be used on historic masonry roads or sidewalks. </li> <li>Exterior Grade Sealant for traffic surfaces shall be a non-sag, gun grade, single or multi-component urethane sealant complying with ASTM C920-05, Type M or S, Grade NS, Class 25, use group NT, M, A and O. The Architect shall select color from manufacturer's full range of colors. </li> </ol>

GUTTER AND ROOFING SEALANTS
<ol type="A"> <li>For joints in metal gutters and slate roofs, provide butyl rubber sealant conforming to the requirements of ASTM C 1085 and  approved by the Architect. See reports 07600.01 and 07631.01 for detailed information on the repair of metal roofs and gutters.</li> </ol>

SANITARY SEALANTS
<ol type="A"> <li>Mildew-resistant silicone sealant conforming to ASTM C920, Type S, Grade NS, Class 25, Use Group NT, G and A. </li> </ol>

ACCESSORY MATERIALS
<ol type="A"> <li>Backer Rod: Required where depth of joint exceeds 1/2 inch. Backer rod shall be closed cell polyethylene or polyurethane foam rod, nonabsorbent to water or gas, of diameter recommended by the manufacturer for the opening width. Product shall comply with ASTM D1623 and ASTM C1083. Verify compatibility of backer rod and sealant before installation. </li> <li>Bond Breaker Tape: Required where backer rod is not employed. As recommended by the sealant manufacturer.</li> <li>Joint primer and cleaner shall be as recommended by the sealant manufacturer for joint surfaces. Contractor shall verify with the manufacturer the need for primer and the correct product for type of substrate on which sealant is to be applied. The manufacturer's literature shall not be used as a basis for determining primer requirements.</li> <li>Masking tape for protection of materials adjacent to joints shall be a non-staining, non-absorbent type compatible with sealant and substrate. </li> </ol> =EXECUTION=

GENERAL
<ol type="A"> <li>Follow manufacturer’s instructions for installation of sealants, backer rods and bond breaker. Install elastomeric sealants in accordance with ASTM 1193.</li> <li>Review the extent of the work with the Architect prior to beginning sealant installation.</li> <li>All scheduled surface cleaning work shall be completed prior to installation of new joint sealants. Coordinate with Contractors responsible for cleaning to avoid delays in work and leakage into the building due to open joints.</li> </ol>

SEALANT INSTALLATION
<ol type="A"> <li>Inspect all joints to receive sealant prior to commencing work for compliance with joint requirements, tolerances and other conditions affecting sealant performance. Notify the Architect of any unsatisfactory conditions. Do not proceed with sealant installation until corrections or adjustments have been made.</li> <li>Clean out joints to receive sealant of all dirt, grease, or other foreign materials. </li> <li>Vacuum or brush joints using non-ferrous brush and blow dry at a pressure not to exceed 500 psi.</li> <li>Install backer rod packed into joint to provide sealant depth recommended by manufacturer. Backer rod shall be selected to allow for a minimum of 30 percent compression of the backing when inserted into the joint. <ol> <li>Do not leave gaps between ends of backer rod.</li> <li>Do not stretch, twist, puncture or tear backer rod.</li> <li>Backer rod installation shall absolutely ensure that sealant adheres to the two opposing sides of the joint only.</li> </ol> </li> <li>Where backer rod is not employed, install bond breaker tape to ensure that sealant adheres to the two opposing sides of the joint only.</li> <li>Tape shoulders of joint with masking tape during installation and tooling of sealant to aid in removal of excess sealant and to prevent staining of adjacent surfaces. Remove tape after tooling of joint.</li> <li>Fill joint completely with sealant in accordance with the manufacturer's instructions.</li> <li>Tool sealant immediately after application to ensure firm, full contact with the inner faces of the joint. Finished bead shall be smooth, continuous, and slightly concave.</li> <li>Clean all excess sealant off adjacent surfaces immediately after tooling and removal of tape. Do not use any cleaners or agents that will stain the sealant or adjacent surfaces.</li> </ol>

FINAL REPORT
<ol type="A"> <li>The Contractor shall provide a final report of completed work including all approved submittals and photographs of the repaired areas taken before, during and after the work.</li> </ol>