14.2. Copper Wall Cladding

SECTION 074210

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THIS SECTION USES THE TERM "ARCHITECT." CHANGE THIS TERM AS NECESSARY TO MATCH THE ACTUAL TERM USED TO IDENTIFY DESIGN PROFESSIONAL AS DEFINED IN THE GENERAL AND SUPPLEMENTARY CONDITIONS.

WALL PANELS ARE PART OF A SYSTEM. COORDINATE WALL PANELS WITH SHEATHING AND AIR BARRIERS COVERING SHEATHING OR WALL SYSTEMS.

FLAT SEAM WALL PANELS ARE USUALLY INSTALLED WITH DRY JOINTS - NO SEALANT OR SOLDER.

PART 1-GENERAL

1.1 SUMMARY

  1. Section Includes:

    EDIT LIST BELOW TO SUIT PROJECT.

    1. Horizontal siding.
    2. Horizontal profiled wall cladding.
    3. Flat-seam copper wall cladding.
    4. Beveled panel cladding.
    5. Corrugated panel cladding.
    6. Standing seam cladding.
    7. Batten seam cladding.
    8. Horizontal seam (Bermuda) cladding.
    9. Soffit panels and cladding.

    RETAIN BELOW FOR FIELD PAINTING (ALSO FOR OTHER FINISHING).

  2. Related Requirements:
    1. Drawings and general provisions of Contract, including General and Supplementary Conditions and Division 01 Specification Sections, apply to this Section.
    2. Division 05 Sections for structural and light-gauge framing.
    3. Division 06 Section for wall sheathing.
    4. Division 07 Section "Thermal Insulation" for wall insulation.
    5. Section 076110 - Copper Roofing.
    6. Section 076210 - Manufactured Copper Roofing Specialties: Accessories on roof other than mechanical and structural items.
    7. Section 076215 - Copper Flashing and Trim: Flashing and other trim not part of roofing.
    8. Section 076220 - Copper Gutters and Downspouts: Gutters and downspouts associated with roofing.
    9. Section 079514 - Copper Expansion Joint Cover Assemblies.

      ABOVE MAY BE EDITED TO IDENTIFY SPECIFIC ITEMS SUCH AS REGLETS, RELIEF VENTS, ROOF EXPANSION ASSEMBLIES, ORNAMENTAL ITEMS, ETC.

    10. Division 07 Section "Joint Sealants" for field-applied panel sealants.
    11. Wood framing and decking is specified in a Division 06 Section.

DELETE ANY OF THE FOLLOWING PROVISIONS WHICH ARE NOT APPLICABLE TO THE TYPE OF WALL CLADDING REQUIRED.

1.2 COORDINATION

  1. Coordinate copper wall cladding with wall air retarders and rain drainage work, including, flashing, gutters, downspouts, trim and construction to provide permanently watertight, secure, and noncorrosive installation.

1.3 PERFORMANCE REQUIREMENTS

DESIGN PROFESSIONAL IS RESPONSIBLE FOR DESIGNING SYSTEM, INCLUDING ANCHORAGE, FASTENER SIZE, AND SPACING.

  1. Installation Requirements: Fabricator is responsible for installing system, including anchorage to substrate and necessary modifications to meet specified and drawn requirements and maintain visual design concepts in accordance with Contract Documents and following installation methods as stipulated in the "Copper in Architecture" handbook published by the Copper Development Association Inc. (CDA)
    1. Drawings are diagrammatic and are intended to establish basic dimension of units, sight lines, and profiles of units.
    2. Make modifications only to meet field conditions and to ensure fitting of system components.
    3. Obtain Architect's approval of modifications.
    4. Provide concealed fastening wherever possible.
    5. Attachment considerations: Account for site peculiarities and expansion and contraction movements so there is no possibility of loosening, weakening and fracturing connection between units and building structure or between components themselves.
    6. Obtain Architect's approval for connections to building elements at locations other than indicated in Drawings.
    7. Accommodate building structure deflections in system connections to structure.
  2. Performance Requirements:
    1. System shall accommodate movement of components without buckling, failure of joint seals, undue stress on fasteners, or other detrimental effects when subjected to seasonal temperature changes and live loads.
    2. Design system capable of withstanding building code requirements for negative wind pressure.
  3. Interface With Adjacent Systems:
    1. Integrate design and connections with adjacent construction.
    2. Accommodate allowable tolerances and deflections for structural members in installation.

1.4 SUBMITTALS

  1. General: Submit the following in accordance with Conditions of Contract and Division 01 Specification Sections.
  2. Product data including copper manufacturer's specifications, installation instructions, and general recommendations for wall cladding applications. Include certification or other data substantiating that materials comply with requirements.

    DELETE BELOW IF DETAILS OF NO IMPORTANCE OR COVERED ADEQUATELY BY WORKING DRAWINGS.

  3. Shop Drawings:
    1. Provide elevations showing seam layout and pattern.
    2. Show manner of forming, joining, and securing copper cladding to Project substrate.
    3. Show expansion joint details and waterproof connections to adjoining work and at obstructions and penetrations.

    DELETE BELOW IF WORK is FULLY CONCEALED, TO BE UNFINISHED, OR FIELD PAINTED, OR IF EXPOSURE is OF NO VISUAL IMPORTANCE OR IS WELL-KNOWN.

  4. Samples consisting of 6-inch (150 mm) or 12-inch (300 mm) square specimens of specified copper wall cladding material.
  5. Certificates: Fabricator's certification that products furnished for Project meets or exceeds specified requirements.

1.5 CLOSEOUT SUBMITTALS

  1. Provide maintenance data in Operations and Maintenance manual for maintaining applied coatings on copper panels.

1.6 QUALITY ASSURANCE

  1. Fabricator's Qualifications: Company specializing in copper sheet metal wall cladding work with three years experience in similar size and type of installations.
  2. Installer: A firm with 3 years of successful experience with installation of copper wall cladding of type and scope equivalent to Work of this Section.
  3. Industry Standard: Except as otherwise shown or specified, comply with applicable recommendations and details of the "Copper in Architecture " handbook published by the Copper Development Association Inc. (CDA). Conform to dimensions and profiles shown.

    DELETE ENTIRE MOCK-UP PROVISION BELOW UNLESS THE EXPENDITURE IS JUSTIFIED BY AN EXTENSIVE, UNUSUAL, OR CRUCIAL APPLICATION OF COPPER WALL CLADDING.

  4. Mock-Up: Before proceeding with final purchase of materials and fabrication of copper wall cladding components, prepare a mock-up of work. Incorporate materials and methods of fabrication and installation identical with project requirements. Install mock-up at wall cladding area location directed by Architect. Retain accepted mock-up as quality standard for acceptance of completed copper wall cladding. If accepted, mock-up may be incorporated as part of copper wall cladding work.
    1. Mock-up area is indicated on Drawings.

      DELETE EITHER ABOVE OR BELOW.

    2. Provide mock-up of sufficient size and scope to show typical pattern of seams, fastening details, edge construction.

1.7 DELIVERY, STORAGE, AND HANDLING

  1. Packing, Shipping, Handling, and Unloading: Protect finish panel faces.
  2. Acceptance at Site: Examine each panel and accessory as delivered and confirm that finish is undamaged. Do not accept or install damaged panels.
  3. Storage and Protection:
    1. Stack pre-formed material to prevent twisting, bending, and abrasions.
    2. Provide ventilation.
    3. Prevent contact with materials which may cause discoloration or staining.

1.8 WARRANTY

  1. Warrant installed system and components to be free from defects in material and workmanship for period of 2 years.
  2. Include coverage against leakage and damages to finishes.

PART 2-PRODUCTS

2.1 MANUFACTURERS

DELETE THIS ARTICLE IF OWNER-IMPOSED OR OTHER PROJECT REQUIREMENTS PROHIBIT MENTION OF MANUFACTURERS' NAMES.

  1. Available Manufacturers: Subject to compliance with requirements, manufacturers offering materials that may be incorporated in the Work include, but are not limited to, the following:

    RETAIN ABOVE FOR NONPROPRIETARY OR BELOW FOR SEMIPROPRIETARY SPECIFICATION. REFER TO DIVISION-1 SECTION "MATERIALS AND EQUIPMENT."

  2. Manufacturers: Subject to compliance with requirements, provide materials by one of the following:

    BELOW ARE EXAMPLES ONLY. RETAIN OR INSERT ONLY THOSE MANUFACTURERS BELOW WHOSE MATERIALS CORRESPOND WITH OTHER REQUIREMENTS AND WHOSE AVAILABILITY AND SUITABILITY FOR APPLICATION INDICATED HAVE BEEN VERIFIED.

    1. Hussey Copper, Ltd.
    2. Aurubis Buffalo, Inc.
    3. PMX Industries Inc.
    4. Revere Copper Products, Inc.

2.2 MATERIALS

  1. Copper Wall Cladding Sheets: Cold-rolled copper sheet complying with ASTM B 370 temper H00, unless otherwise indicated, and as follows:
    1. Weight: 16 oz. per sq. ft. (0.0216-inch thick) (0.55 mm) unless otherwise indicated.

      DELETE ABOVE OR BELOW OR EDIT AS APPROPRIATE. REFER TO MANUFACTURERS' LITERATURE FOR SELECTION OF THICKNESS APPROPRIATE TO APPLICATION INDICATED.

    2. Weight: 20 oz. per sq. ft. (0.0270-inch thick) (0.69 mm) unless otherwise indicated.
  2. Miscellaneous Materials: Provide materials and types of fasteners, protective coatings, separators, sealants and accessory items as recommended by copper sheet manufacturer for copper wall cladding work, except as otherwise indicated.

    REVISE BELOW WITH SPECIFIC REQUIREMENTS WHERE DESIRED FOR PROJECT.

  3. Accessories: Except as indicated as work of another specification Section, provide components required for a complete wall cladding system, including trim, copings, fascias, ridge closures, cleats, seam covers, battens, flashings, gutters, louvers, sealants, gaskets, vents, and closure strips. Match materials and finishes of wall cladding .
    1. Sealing Tape: Pressure-sensitive 100 percent solids polyisobutylene compound sealing tape with release paper backing. Provide permanently elastic, nonsag, nontoxic, nonstaining tape.
    2. Joint Sealant: One-part, copper compatible elastomeric polyurethane, polysulfide, butyl or silicone rubber sealant as tested by sealant manufacturer for copper substrates. Refer to Division 07.

      SELECT WALL CLADDING TYPE BELOW.

    3. Cleats:
      1. Concealed type as indicated in the "Copper in Architecture" handbook published by the Copper Development Association Inc. (CDA) for [wall panels] [flat-seam wall cladding] to resist negative wind pressure.
      2. Fabricate cleats to allow thermal movement of copper wall cladding panels while preventing copper panel distortion due to negative wind pressure.
    4. Trim, [Soffits,] Closure Pieces, and Accessories:
      1. Same material, thickness, and finish as adjacent copper wall cladding panels, formed to required profiles.
      2. Comply with standards conforming to recognized industry standard sheet metal practice.
    5. Flashings: Formed copper sheet, minimum 16 oz. per sq. ft. (0.0216 inch thick) (0.55 mm) unless otherwise indicated; finished to match panels.
  4. Bituminous Coating: SSPC-Paint 12, Cold-Applied Asphalt Mastic (Extra Thick Film), nominally free of sulfur, compounded for 15-mil dry film thickness per coat.

    COORDINATE WITH BUILDING AIR BARRIER SYSTEM. DELETE BELOW IF NOT REQUIRED.

  5. Building Paper: Grade D, 60-minute water resistance minimum, ASTM D779.

    USE BELOW UNDER COPPER INSTALLED ON building paper SHEETS.

  6. Paper Slip Sheet: Minimum 4-lb. red rosin-sized building paper.
  7. Nails for Wood Substrates: Copper or hardware bronze, 0.109 inch minimum not less than 7/8-inch (22 mm) long barbed with large head.
  8. Screws & Bolts: Copper, bronze, brass, or passivated stainless steel (300 Series) of sufficient size and length to sustain imposed stresses.
    1. Neoprene (resilient) gasketed washers tested to be compatible with copper and exposed screw head color matched to adjacent panel where exposed. Use exposed fasteners only where absolutely necessary to attach trim and at corrugated metal panels.
  9. Fixed cleats: Same weight as wall cladding. 2-inch (50-mm) wide x 3-inch (75-mm) long.
  10. Rivets:
    1. Pop Rivets: 1/8-inch (3-mm) to 3/16-inch (4.5-mm) diameter, with solid brass mandrels.
    2. Provide solid copper rivet (tinner's rivets) where structural integrity of seam is required.

2.3 FABRICATION

  1. General Metal Fabrication: Shop-fabricate work to greatest extent possible. Comply with details shown and with recognized industry standards as shown in the "Copper in Architecture" handbook published by the Copper Development Association Inc. (CDA) and other recognized industry practices. Fabricate for waterproof and weather-resistant performance with expansion provisions for running work, sufficient to permanently prevent leakage, damage, or deterioration of the work. Form work to fit substrate. Comply with material manufacturer's instructions and recommendations for forming material. Form exposed copper work without excessive oil-canning, buckling, and tool marks, true to line and levels indicated, with exposed edges folded back to form hems.
    1. Fabricate to allow for adjustments in field for proper anchoring and joining.
    2. Form sections true to shape, accurate in size, square, free from distortion and defects.
    3. Cleats: Fabricate cleats and starter strips of same or thicker material as sheet, interlockable with sheet in accordance with CDA recommendations.
    4. Flat Seam Panel Seams:
      1. Fabricate seams for panels to be installed in overlapped, interlocking shingle manner.
      2. Fold two adjacent edges over 180 degrees for width of 3/4 inch and other two adjacent edges under 3/4 inch (19 mm). Refer to CDA "Copper in Architecture" handbook.
      3. Fabricate flat seam wall cladding from pans 18 inches (450 mm) by 24 inches (600 mm) in size.
      4. Form interlocking seams with cleats folded into seam
    5. Flat Siding Panels:
      1. Interlocking flat panel without stiffener ribs.
      2. Factory tongue and groove type interlock to receive concealed fasteners.
      3. Profile and size as indicated on Drawings.
      4. Form interlocking seams with cleats folded into seam
    6. Beveled Metal Panel:
      1. Overlapping and interlocking beveled panel.
      2. Factory fabricated for concealed cleats and fasteners.
      3. Profile and size as indicated on Drawings.
      4. Form interlocking seams with cleats folded into seam
    7. Corrugated Panels: Overlapping panels for exposed fasteners.
      1. Match selected profile.
      2. Corrugations sizes as indicated.
    8. Standing Seam Panels:
      1. Fabricate pans to interlock standing seam with center to center seam spacing as indicated on Drawings.
      2. Fabricate interlocking seams to heights and patterns indicated.
      3. Form interlocking seams with cleats folded into seam
      4. Form overlapping and interlocking transverse joints.
    9. Batten Seam Panels:
      1. Fabricate pans to create center to center batten seam spacing as indicated on Drawings.
      2. Fabricate battens to sizes indicated.
      3. Form interlocking seams with cleats folded into seam
      4. Form overlapping and interlocking transverse joints.
      5. Provide ½-inch (13-mm) single lock seam at batten caps.
    10. Horizontal Seam (Bermuda) Panels:
      1. Fabricate pans with long runs and pan size as indicated on Drawings.
      2. Form interlocking seams with cleats folded into seam.
      3. Seam height of ¾-inch (19-mm) offset from adjacent panel.
      4. Form overlapping transverse joints.
  2. Seams: Fabricate seams in copper sheet with flat seams.
  3. Expansion Provisions: Where lapped or bayonet-type expansion provisions in work cannot be used, or would not be sufficiently water/weatherproof, form expansion joints of intermeshing hooked flanges, not less than 1-inch (25-mm) deep, filled with mastic sealant (concealed within joints).
  4. Sealant Joints: Where movable, non-expansion-type joints are indicated or required for proper performance of work, form copper to provide for proper installation of elastomeric sealant, in compliance with CDA standards.
  5. Separations: Provide for separation of copper from noncompatible metal or corrosive substrate by coating concealed surfaces at locations of contact, with bituminous coating or other permanent separation as recommended by manufacturer/fabricator.

2.4 FINISHES

  1. Natural weathering mill finished copper. No applied finish.
    ***** OR *****

    REVIEW PAINT SELECTION WITH COATINGS MANUFACTURER, REFER TO DIVISION 09.

  2. To retard natural weathering, apply a uniform coating of high-grade paraffin oil, or a clear lacquer coat.

    CLEAR COATINGS TO RETARD WEATHERING NOT RECOMMENDED DUE TO MAINTENANCE REQUIREMENTS.

  3. Clear Lacquer Coating:
    1. Clear, Organic Coating: Clear, air-drying, acrylic lacquer specially developed for coating copper alloy products, equivalent to Incralac by StanChem applied by air spray in 2 coats per manufacturer's directions, with interim drying, to total thickness of 1.0 mil.

PART 3-EXECUTION

3.1 EXAMINATION

  1. General: Examine conditions and proceed with work when substrates are ready.
  2. Confirm that substrate system is even, smooth, sound, clean, dry, and free from defects.
  3. Verify wall openings, pipes, sleeves, ducts, and vents through wall assembly are solidly set, and fastener strips located.

3.2 PREPARATION

  1. Clean surfaces to receive copper wall cladding . Substrate to be smooth and free of defects. Drive all projecting nails or other fasteners flush with substrate.

    COORDINATE WITH BUILDING AIR BARRIER SYSTEM OR USE BUILDING PAPER AS FOLLOWS.

  2. Building Paper:
    1. Weather lap sheets 2 inches (50 mm).
    2. Lap sheet 6 inches (150 mm) at ends.
    3. Attach to sheathing in accordance with sheathing manufacturer's recommendations to prevent leaks and sheathing deterioration.
    4. Provide 2 layers with joints shingled for overlaps.
  3. Install building paper and paper slip sheet on substrate under copper wall cladding to greatest extent possible unless otherwise recommended by manufacturer of sheet metal. Paper slip sheets must be installed over underlayment. Use adhesive for temporary anchorage to minimize use of mechanical fasteners under copper wall cladding. Lap joints 2 inch (50 mm) minimum.

3.3 INSTALLATION

  1. Manufacturer's Recommendations: Except as otherwise shown or specified, comply with recommendations and instructions of manufacturer of copper being fabricated and installed.
  2. General:
    1. Separate dissimilar metals by painting each metal surface in area of contact with a bituminous coating, by applying rubberized asphalt or butyl underlayment to each metal surface, or by other permanent separation as recommended by manufacturers of dissimilar metals.
    2. Form and fabricate sheets, seams, strips, cleats, flashings, edge treatments, and other components of copper wall cladding to profiles, patterns, and drainage arrangements shown and as required for permanently leak proof construction. Provide for thermal expansion and contraction of the work, as indicated. Seal joints as shown and as required for leak proof construction. Shop-fabricate materials to greatest extent possible.
    3. Sealant-Type Joints: Where sealant-filled joints are used, embed hooked flanges of joint members not less than 1 inch (25 mm) into sealant. Form joints to conceal sealant completely. When ambient temperature is moderate at time of installation, 40 degrees to 70 degrees F (4 degrees to 21 degrees C), set joint members for 50 percent movement either way. Adjust setting proportionately for installation at higher ambient temperatures. Do not install sealant-type joints at temperatures below 40 degrees F (4 degrees C). Comply with requirements of Division 07 "Joint Sealant" Sections for handling and installing sealants.
    4. Fabricate and install work with lines and corners of exposed units true and accurate. Form exposed faces flat and free of buckles, excessive waves, and avoidable tool marks considering temper and reflectivity of metal. Provide uniform, neat seams. Except as otherwise shown, fold back sheet metal to form a hem on concealed side of exposed edges.
    5. Conceal fasteners and expansion provisions where possible in exposed work, and locate so as to minimize possibility of leakage. Cover and seal fasteners and anchors as required for a tight installation.

    DELETE FLAT SEAM CLADDING TYPE BELOW IF NOT USED.

  3. Flat Seam Wall Cladding:
    1. Install copper work in accordance with the "Copper in Architecture " handbook published by the Copper Development Association Inc. (CDA) for flat seam joints.
    2. Flat Seam Metal Wall Cladding Panels: Fasten system to substrate with concealed metal cleats and screws/nails at spacing required to resist negative wind pressure.
    3. Align, level, and plumb system with structure.
    4. Set panels with horizontal [diagonal] orientation.
    5. Fasten cleats using cleats mated to folded flat seams and fastener pattern to resist design loads with screws or barbed nails of sufficient length to penetrate substrate.
    6. Fully seat adjacent panel to on two sides to achieve continuous engagement of seam joint.

    DELETE STANDING SEAM CLADDING TYPE BELOW IF NOT USED.

  4. Standing Seam Cladding:
    1. Fold lower end of each pan under ¾-inch (19-mm). Slit fold one inch (25-mm) away from corner to form tab where pan turns up to make standing seam. Fold upper end of each pan over 2-inches (50-mm). Hook fold on lower end of upper pan into fold on upper end of underlying pan.
    2. Apply pans beginning at bottom of wall.
    3. Finish standing seams 1-inch (25-mm) [1 ½-inch (38-mm)] high. Bend up one side edge 1 ½-inch (38-mm) [ 2-inch (50-mm) ] and other 1 ¾-inch (44-mm) [ 2 ¼-inch (66-mm )] . Make first fold ¼-inch (6-mm) wide single fold and second fold ½-inch (13-mm) wide, providing locked portion of standing seam with 5 plies in thickness.

    DELETE BATTEN SEAM CLADDING TYPE BELOW IF NOT USED.

  5. Batten Seam Cladding:
    1. Turn up sides of sheets to extend above top of battens ½-inch (13-mm). Turn this ½-inch (13-mm) at right angles to battens.
    2. Form cross seams with ¾-inch (19-mm) fold under on lower end and 2-inch (50-mm) fold over on upper end. Slit folds in cross seams at each corner 1-inch (25-mm) in from batten to form tab. Hook fold on lower end of pan into fold on upper end of underlaying pan.
    3. Apply pans beginning at bottom of wall.
    4. Place cover strips over battens, locking edges with flanges of pan malletted down against sides of battens. Cover batten ends with cap folded and locked into extensions of batten covers and vertical legs of pans.

    DELETE HORIZONTAL SEAM CLADDING TYPE BELOW IF NOT USED.

  6. Horizontal Seam (Bermuda) Panels:
    1. Install wood nailers parallel to long seam.
    2. Infill between nailers with tapered insulation or fiberboard.
    3. Start panel installation at bottom of wall.
    4. Interlock cleat into joints of adjacent panel.
    5. Fasten cleats to wood nailers on 12-inch (300-mm) centers.
    6. Install overlapping transverse joints in accordance with CDA "Copper in Architecture" handbook.
  7. Fastening:
    1. Provide expansion and contraction movement capability as necessary.
    2. Permanently shim and fasten panel system to substrate system at spacing required by panel manufacturer.
    3. Align, level, and plumb, within specified tolerances.
    4. Use concealed fasteners for flat panels; exposed fasteners may only be used on portions of applied trim if necessary.
    5. Locate and space exposed fasteners in true vertical and horizontal alignment, unless indicated otherwise by Architect.
    6. Use proper tools to obtain controlled uniform compression for positive seal without rupture of resilient washer.
  8. Install accessories, flashings, closures, and related trim to provide complete watertight system.
  9. Coordinate installation of panels with adjacent construction to ensure watertight enclosure.
  10. Tolerances:
    1. Maximum offset from true alignment between adjacent members butting or in line: 1/8-inch (3-mm).
    2. Maximum variation from plane or location indicated on Drawings: ¼-inch (6-mm).
  11. Field adjust and align using adjustments within fastening methods.

3.4 CLEANING

  1. Remove protective film (if any) from exposed surfaces of copper wall cladding promptly upon installation. Strip with care to avoid damage to finishes.
  2. Upon completion of each area of soldering, carefully remove flux and other residue from surfaces. Neutralize acid flux by washing with baking soda solution, and then flushing clean water rinse. Use special care to neutralize and clean crevices.
  3. Clean exposed metal surfaces of substances that would interfere with normal oxidation and weathering.

3.5 PROTECTION

  1. Provide final protection in a manner acceptable to installer that ensures that copper wall cladding is without damage or deterioration at time of Substantial Completion.