2016 Capital Improvement Project REHABILITATION OF METAL ROOFING SECTION REHABILITATION OF METAL ROOFING PART 1 - GENERAL

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1 REHABILITATION OF METAL ROOFING SECTION REHABILITATION OF METAL ROOFING 1.1 RELATED DOCUMENTS PART 1 - GENERAL A. Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 01 Specification Sections, apply to this Section. 1.2 SUMMARY A. This Section includes the following: 1. Detail course on metal roof panel joints, fasteners, and flashings, and cleaning in preparation for metal roof coating system. 2. Application of elastomeric acrylic based coating system on metal roofing, flashings and skirt. 1.3 MATERIALS OWNERSHIP A. Demolished materials shall become Contractor's property and shall be removed from Project site. 1.4 DEFINITIONS A. Roofing Terminology: Refer to ASTM D 1079 and glossary in NRCA's "The NRCA Roofing and Waterproofing Manual" for definition of terms related to roofing work in this Section. B. Existing Roofing System: Metal roofing and components and accessories. C. Roofing Coating Preparation: Existing roofing that is to remain and be prepared to accept restorative coating application. D. Existing to Remain: Existing items of construction that are not indicated to be removed. 1.5 ACTION SUBMITTALS A. Product Data: For each type of product specified. 1.6 INFORMATIONAL SUBMITTALS A. Manufacturer s Certificate: Submit certificate, indicating products intended for Work of this Section, including product names, with statement indicating that products to be provided meet the requirements of the Contract Documents. B. Installer Certificates: Signed by roofing system manufacturer certifying that Installer is approved, authorized, or licensed by manufacturer to install roofing system. C. Product Test Reports: Based on evaluation of comprehensive tests performed by manufacturer and witnessed by a qualified testing agency, for components of roofing rehabilitation system. D. Warranties: Unexecuted sample copies of specified warranties. E. Inspection Reports: Daily reports of Roofing Inspector. Include description of work performed, tests performed, defective work observed, and corrective actions required and carried out. 1.7 CLOSEOUT SUBMITTALS A. Maintenance Data: To include in maintenance manuals.

2 REHABILITATION OF METAL ROOFING B. Completion Report: Report from manufacturer showing photos taken during every-other-day technical inspections, and descriptions of work stages completed. C. Warranties: Executed copies of approved warranty forms. 1.8 QUALITY ASSURANCE A. Installer Qualifications: Engage an experienced installer to perform Work of this Section who has specialized in installing cold process roofing systems; who is approved, authorized, or licensed by the roofing system manufacturer to install manufacturer s product; and who is eligible to receive and issue the roofing manufacturer s warranty as specified. B. Applicators to include a list of three (3) projects completed within the last three years, of similar size and within 75 miles of project site, using the submitted manufacturer's products. List to include names and full contact information for the projects, architects and Owners and shall be submitted with bid. Owner's Representative may require copies of existing warranties for referenced projects. 1. Bids that fail to submit required references may be rejected without cause by the Owner's Representative. C. Inspection Reports: Provide copies of the roofing system manufacturer s inspection reports noted during and at the completion of the new roof installation. Manufacturer s Technical (non-sales) Representative must inspect roof installation every other day and report progress to Owner s Representative. Provide progress photos for application of each operation of roofing system. In addition to regular inspections, Manufacturer s Technical (non-sales) Representative shall be present for roof work starts at each section. Manufacturer s Technical Representative shall provide proof of no less than 10 years experience in the Roofing Industry. D. Roofing Inspector Qualifications: A full time Technical Representative of manufacturer (nonsales) experienced in the installation and maintenance of the specified roofing system, qualified to perform roofing observation and inspection specified in Field Quality Control Article, to determine Installer s compliance with the requirements of this Project, and approved by the manufacturer to issue warranty certification. 1. The presence and activity of the manufacturer's Technical Representative, Independent Representative and/or Owner's Representative shall in no way relieve the contractor of contract responsibilities or duties. 2. It is the sole responsibility of the installing Contractor to contact the roofing manufacturer s inspector by phone on the morning of each day that roofing materials are being installed. E. The Roofing Inspector shall be one of the following: 1. An authorized full-time technical employee of the manufacturer with 10 years experience in commercial roofing. 2. If manufacturer does not employ full time technical personnel, inspection personnel shall be certified as a Registered Roof Observer by the Roof Consultants Institute, and shall be experienced in the installation and maintenance of the specified roofing system and qualified to determine Installer s compliance with the requirements of this Project. F. Source Limitations: Obtain roofing system components from or approved in writing by roofing system manufacturer. G. If Contractor chooses to bid a substitute system, Contractor must bid specified system and submit separate bid for the substitute system. Substitute system must be identified publicly during the pre-bid conference to give all bidders equal opportunity. Bidding contractors proposing

3 REHABILITATION OF METAL ROOFING substitutes shall submit the following to Architect a minimum of 10 (ten) business days prior to bid date: 1. Written explanation of why the substitute system should be considered. 2. Accredited third-party testing certifications showing that the physical and performance characteristics of the substitute system s products will meet or exceed those of the specified materials. 3. Printout of current UL listing, meeting or exceeding the required wind uplift and fire rating requirements, showing exact proposed substitute materials. 4. A written summary sheet showing a comparison of physical properties all of the specified products against the proposed substitute products; including printed versions of all manufacturers current product data sheets for all products being proposed or compared in the required summary. 5. List minimum five (5) roofing projects, installed within 50 miles of the project site, using the exact combination of proposed substitute materials. Include all project contact information including project size, names, addresses and contact phone numbers of Owners and Architects involved. Include copies of current warranties for verification. 6. Smallest standard package of, and product data sheets for, all proposed substitute adhesives, mastics, sealants, base coat, top coat, reinforcements, ply sheets and flashings. 7. Any proposed substitute system that the Architect deems as qualified to compete for the project will be acknowledged by written addendum before the bid date. 8. Voluntary alternate roofing systems submitted by the low bid Contractor, without preapproval acknowledged by the Architect through the published addendum process, may be rejected without cause by the Owner's Representative. H. Pre-Bid Roofing Conference: Conduct conference at Project site. 1. Roofing Rehabilitation Preinstallation Conference: Conduct conference at Project site to comply with requirements in Division 01 Section "Project Management and Coordination." Review methods and procedures related to roofing system. 2. Meet with Owner; roofing coating materials manufacturer's representative; roofing coating Installer including project manager and foreman; and installers whose work interfaces with or affects rehabilitation including installers of roof accessories and roofmounted equipment requiring removal and replacement as part of the Work. 3. Review methods and procedures related to coating preparation, including metal roofing coating system manufacturer's written instructions. 4. Review temporary protection requirements for existing roofing system that is to remain uncoated, during and after installation. 5. Review roof drainage during each stage of coating and review roof drain plugging and plug removal procedures. 6. Review and finalize construction schedule, and verify availability of materials, Installer's personnel, equipment, and facilities needed to make progress and avoid delays. 7. Review base flashings, special roofing details, drainage, penetrations, equipment curbs, and condition of other construction that will affect coating. 8. Review HVAC shutdown and sealing of air intakes. 9. Review shutdown of fire-suppression, -protection, and -alarm and -detection systems. 10. Review governing regulations and requirements for insurance and certificates if applicable. 11. Review existing conditions that may require notification of Owner before proceeding.

4 REHABILITATION OF METAL ROOFING PROJECT CONDITIONS A. Weather Limitations: Proceed with rehabilitation work only when existing and forecasted weather conditions permit Work to proceed without water entering into existing roofing system or building. B. Store all materials prior to application at temperatures between 60 and 90 deg. F. C. Apply coatings within range of ambient and substrate temperatures recommended by manufacturer. Do not apply materials when air temperature is below 50 or above 110 deg. F. D. Do not apply roofing in snow, rain, fog, or mist. E. Protect building to be rehabilitated, adjacent buildings, walkways, site improvements, exterior plantings, and landscaping from damage or soiling from rehabilitation operations. F. Maintain access to existing walkways, corridors, and other adjacent occupied or used facilities. G. Daily Protection: Coordinate installation of roofing so insulation and other components of roofing system not permanently exposed are not subjected to precipitation or left uncovered at the end of the workday or when rain is forecast. H. Owner will occupy portions of building immediately below re-coating area. Conduct re-coating so Owner's operations will not be disrupted. Provide Owner with not less than 24 hours' notice of activities that may affect Owner's operations WARRANTY A. Manufacturer's Warranty for Roof Rehabilitation: Written warranty in which Manufacturer agrees to repair roof rehabilitation installations that fail due to defects in rehabilitation materials or workmanship within specified warranty period. 1. Warranty Period: 12 years from date of completion of rehabilitation work. 2. Failures include, but are not limited to, the following: 3. Rehabilitated membrane failures including rupturing or cracking due to a manufacturing or installation defect. 4. Deterioration of applied rehabilitation materials beyond normal weathering. 5. Limit of Warranty Coverage for Repair of Roof Rehabilitation: Not to exceed original purchase price of manufacturer's recoating materials, except that manufacturer may elect to apply the limit amount toward the following: B. Qualified Installer Warranty Requirement: Installer must meet requirements of Quality Assurance Article. C. Installation Inspection Warranty Requirement: By Roofing Inspector in accordance with requirements of Quality Assurance Article. D. Manufacturer Inspection Requirement: By manufacturer's technical (non-sales) representative, to report maintenance responsibilities to Owner necessary for preservation of Owner's warranty rights. The cost of manufacturer's annual inspections and preventive maintenance is included in the Contract Sum. a. Inspections to occur in Years two (2) and five (5) following completion. E. Installer/Roofing Contractor Warranty: Submit roofing Installer's warranty, signed by Installer, covering the Work of this Section and related Sections indicated above, including all components of both roof coating systems. F. The warranty shall guarantee material and workmanship for water-tightness and against all leaks for a period of two (2) years. During the two-year period, the contractor shall respond and fix all

5 REHABILITATION OF METAL ROOFING reported leaks within 24 hours from time of notification, and fix all leaks without any cost to the Owner. G. Warranty Period: Two years from date of Substantial Completion. 2.1 MANUFACTURERS PART 2 - PRODUCTS A. Basis-of-Design Manufacturer/Product: The roof system specified in this Section is based upon products of Tremco, Inc., that are named in other Part 2 articles. 1. Subject to compliance with requirements, provide the named product by one of the following: a. Tremco, Inc. b. Sika c. Ecology 2.2 PERFORMANCE REQUIREMENTS A. General: Provide coated metal roofing and modified-bitumen-lined gutter system that remains weathertight; does not permit the passage of water; and resists thermally induced movement, and exposure to weather without failure. B. Material Compatibility: Provide roofing materials that are compatible with one another under conditions of service and application required, as demonstrated by roofing manufacturer based on testing and field experience. C. The following coating products are not equals to those specified and therefore not permitted on this project: Polymethyl-methacrylate (PMMA), silicone, catalyzed resins and/or components are not permitted. 2.3 MATERIALS, GENERAL A. General: Rehabilitation materials recommended by roof coating manufacturer for intended use and compatible with components of existing metal and modified-bitumen roofing systems. 2.4 METAL ROOF COATING MATERIALS A. Metal Roof & Skirt Coating: ASTM D 6083, elastomeric acrylic roof coating system consisting of a separately applied base coat and two top coats. 1. Tremco, SOLARGARD 6083 Base Coat, SOLARGARD 6083 White Top Coat. (Basisof-Design) 2. Sika, Sikacoat BC420, Sikacoat FC3500 White. 3. Ecology, ERS-White Roof Coating Base Coat, ERS-White Roof Coating Top Coat. B. Metal Roof & Skirt Elastomeric Seam Sealer: One part urethane/polyurethane seam sealer for metal panel seams and fasteners. 1. Tremco, SOLARGARD Seam Sealer (Basis-of-Design). 2. Sika, Sikacoat S Ecology, ERS-M10. C. Metal Roof & Skirt Metal Rust Primer: One-part metal and rust primer. 1. Tremco, SOLARGARD Rust Primer WB (Basis-of-Design) 2. Sika, Sikacoat P400R. 3. Ecology, ERS-RC Primer.

6 REHABILITATION OF METAL ROOFING AUXILIARY ROOFING REHABILITATION MATERIALS A. General: Auxiliary materials recommended by roofing system manufacturer for intended use and compatible with existing roofing system and roofing coating system. B. Seam Reinforcing Mesh: Polyester mesh reinforcement, four-inch minimum width. C. Sealant: Single component, high solids, moisture curing, urethane sealant. D. Fasteners: Factory-coated steel fasteners and metal plates meeting corrosion-resistance provisions in FM 4470; designed for fastening metal roofing components to substrate; tested by fastener manufacturer for required pullout strength; and acceptable to roofing system manufacturer. E. Metal Flashing Sheet: Provide metal flashing sheet matching type, thickness, finish, and profile of existing metal flashing and trim. 3.1 EXAMINATION PART 3 - EXECUTION A. Examine existing roofing substrates, with Installer present, for compliance with requirements and for other conditions affecting application and performance of roof coatings B. For the record, prepare written report, endorsed by Installer, listing conditions detrimental to performance. 1. Verify compatibility with and suitability of substrates. 2. Verify that substrates are visibly dry and free of moisture. 3. Verify that metal roofing is free of rust affecting structural integrity of roofing, or other indications of impending metal roof system failure. C. Application of coatings indicates acceptance of surfaces and conditions. 3.2 PREPARATION A. Complete abatement of hazardous materials materials, following all prescribed legal requirements, as specified separately. B. Owner will occupy portions of building immediately below reroofing area. Conduct reroofing so Owner's operations will not be disrupted. Provide Owner with not less than 72 hours' notice of activities that may affect Owner's operations. C. Coordinate work activities daily with Owner so Owner can place protective dust or water leakage covers over sensitive equipment or furnishings, shut down HVAC and fire-alarm or detection equipment if needed, and evacuate occupants from below the work area if desired. D. Before working over structurally impaired areas of deck, notify Owner to evacuate occupants from below the affected area. Verify that occupants below the work area have been evacuated before proceeding with work over the impaired deck area. E. Protect building area to be repaired, adjacent buildings, walkways, site improvements, exterior plantings and landscaping from damage or soiling from reroofing operations. F. Maintain access to existing walkways, corridors, and other adjacent occupied or used facilities. G. Owner assumes no responsibility for condition of area to be reroofed. H. Conditions existing at time of the prebid conference and walk-through will be maintained by Owner as far as practical.

7 REHABILITATION OF METAL ROOFING I. Protect existing membrane roofing system and newly installed roofing system that will remain during roof preparation, wet area removals and infills. 1. Loosely lay 1-inch minimum thick, extruded polystyrene (XPS) insulation over the existing roofing membrane. Loosely lay 15/32-inch plywood or OSB panels over XPS. Extend XPS past edges of plywood or OSB panels a minimum of 1 inch. 2. Limit traffic and material storage and staging to areas of existing roofing membrane that have been protected. 3. Maintain temporary protection, ballast properly, and leave in place until replacement roofing has been completed. J. Protect existing membrane roofing system and newly installed roofing system that will remain during roof preparation, wet area removals, infills and patching. K. Shut down air intake equipment in the vicinity of the Work in coordination with the Owner. Cover air intake louvers before proceeding with rehabilitation work that could affect indoor air quality or activate smoke detectors in the ductwork 1. Verify that rooftop utilities and service piping affected by the Work have been shut off before commencing Work. L. Maintain roof drains in functioning condition to ensure roof drainage at end of each workday. Prevent debris from entering or blocking roof drains and conductors. Use roof-drain plugs specifically designed for this purpose. Remove roof-drain plugs at end of each workday, when no work is taking place, or when rain is forecast M. Do not permit water to enter into or under existing metal roofing system components that are to remain. 3.3 ROOFING COATING PREPARATION A. Metal Roofing Surface Preparation: B. Remove ridges, buckles, failed or loose roofing fasteners, and other substrate irregularities from existing metal roofing that would inhibit application of uniform, weathertight coating. C. Repair metal roofing at locations where irregularities have been removed. D. Provide replacement fasteners where required. E. Provide additional fasteners where required to meet performance requirements. F. Remove debris from roof surface. G. Clean mechanically stripped roofing substrate of contaminants such as dirt, debris, oil, and grease that can affect adhesion of coating by power washing at minimum 2000 psi. Allow to dry thoroughly. H. Verify that existing substrate is dry before proceeding with application of coating. I. Uplift Securement: As directed by manufacturer s technical inspector, after mechanical stripping has been completed, provide additional uplift securement for existing metal roofing system with new screws and plates, applied to each roof zone at the following densities: 1. Field of roof, one fastener for every 2 square feet. 3.4 FLASHING REPAIR A. Repair existing base flashings around parapets, curbs, walls, and penetrations. B. Do not damage metal flashings that are to remain.

8 REHABILITATION OF METAL ROOFING C. Replace metal flashings damaged during preparation work with counter flashings of same metal, weight or thickness, and finish. D. Repair flashings, copings, and other roof-related sheet metal and trim elements. Reseal joints, replace loose or missing fasteners, and replace components where required to leave in a watertight condition. 3.5 ROOF COATING APPLICATION A. Primer: Prime entire prepared metal roofing areas with metal primer at manufacturer s recommended application rate and allow to dry. B. Detail Course: C. Metal Roofing & Skirt: Coat horizontal and vertical seams with detail course of elastomeric brush grade sealer, working material into overlaps and around all fasteners to completely encapsulate. 1. Four-inch wide fabric should be incorporated into the repair for areas of high stress, including flashings and transition areas. 2. Provide detail course at transition from metal skirt to counter flashings. 3. Provide bead of urethane sealant beneath eave edge of metal roofing where roofing meets the metal skirt below. 4. If left uncoated for more than 72 hours, re-primer needs to be applied before installing the coating system. D. Coating System: Once detail course has adequately cured, apply the following minimum thicknesses of base coat and finish coat, according to manufacturer's written instructions, and as follows: 1. Metal Roofing & Skirt: 2. Base Coat: Apply at rate of one (1) gallons per 100 square feet to provide 16 wet mils coverage. a. Apply base coat in one single coat. 3. Top Coat: Apply at total rate one (1) gallon per 100 square feet to provide 16 total wet mils coverage. a. Apply top coat in 2 separate coats, at.50 gallons per 100 square feet at 8 wet mils per coat, to provide total 16 wet mils. 4. Increase application rates by 15 percent for uneven and non-smooth metal roof surface. 3.6 FIELD QUALITY CONTROL A. Manufacturer s Technical Representative must inspect roof installation every other day and report progress to Owner s Representative. 1. Manufacturer must provide a photo summary report, showing installation methods and conditions, to the Owner's Representative at the completion of the project. B. Final Roof Inspection: Arrange for roofing system manufacturer's technical personnel to inspect roofing installation on completion and submit report to Architect. 1. Notify Architect or Owner 24 hours in advance of date and time of final inspection. 2. Results will be made available to Owner s Representative in written form. Any defects found within the new roof coating system installation will be removed and replaced at the installing contractor s expense. 3. Repair or remove and replace components of roofing coating systems where test results or inspections indicate that they do not comply with specified requirements. 4. Additional testing and inspecting, at Contractor's expense, will be performed to determine compliance of replaced or additional work with specified requirements.

9 REHABILITATION OF METAL ROOFING C. Contractor to repair or remove and replace components of roof coating system where test results or inspections indicate that they do not comply with specified and warranty requirements. 3.7 PROTECTING AND CLEANING A. Protect roofing system from damage and wear during remainder of construction period. B. Correct deficiencies in or remove coating that does not comply with requirements, repair substrates, and reapply coating. C. Clean overspray and spillage from adjacent construction using cleaning agents and procedures recommended by manufacturer of affected construction. END OF SECTION