1-0 SPECS 07510.doc

IDC Base Roof Repair

DIVISION 7 – THERMAL & MOISTURE PROTECTION

SECTION 07600 – SHEET METALWORK

PART 1 – GENERAL

1.01 APPLICABLE PUBLICATIONS: The publications listed below form a part of this specification to the extent referenced. The publications are referred to in the text by basic designation only.

A. Federal Specification (Fed Spec):

UU-B-790a Building Paper, Vegetable Fiber: (Kraft, Water-

& Int Am-1 proofed, Water Repellent and Fire Resistant)

B. American Society for Testing and Materials (ASTM) Publications:

A 167-82 Stainless and Heat-Resisting Chromium-Nickel

Steel Plate, Sheet, and Strip

A 525-83 General Requirements for Steel Sheet, Zinc-

Coated (Galvanized) by the Hot-Dip Process

A 527-85 Steel Sheet, Zinc-Coated (Galvanized) by the

Hot-Dip Process, Lock-Forming Quality

B 101-83 Lead-Coated Copper Sheets

B 221-83 Aluminum-Alloy Extruded Bars, Rod, Wire, Shapes, and Tubes

B 370-83 Copper Sheet and Strip for Building Construction

B 486-74 Paste Solder

(R 1980)

B 560-81 Copper-Clad Stainless Steel Sheet and Strip for

Building Construction

D 226-82 Asphalt-Saturated Organic Roofing Felt Used in

Roofing and Waterproofing

D 751-79 Testing Coated Fabrics

D 1670-74 Failure End Point in Accelerated and Outdoor

Weathering of Bituminous Materials

D 1784-81 Rigid Poly (Vinyl Chloride) (PVC) Compounds and

Chlorinated Poly (Vinyl Chloride) (CPVC)

Compounds

D 2247-68 Testing Coated Metal Specimens at 100% Relative

(R 1980) Humidity

D 2822-75 Asphalt Roof Cement

(R 1982)

E 96-80 Water Vapor Transmission of Materials in Sheet

Form

G 7-77a Atmospheric Environmental Exposure Testing of

Nonmetallic Materials

1.02 GENERAL REQUIREMENTS: Sheet metalwork shall be accomplished to form weathertight construction. Work shall be installed without waves, warps, buckles, fastening stresses or distortion and shall allow for expansion and contraction. Cutting, fitting, drilling, and other operations in connection with sheet metal required to accommodate the work of other trades shall be performed by sheet metal mechanics. Exposed edges shall be hemmed. Bottom edges of exposed vertical surfaces shall be angled to form angle drips. Flashing at the end of a run shall be formed into a three-dimensional configuration to direct water to the outside of the system. Joints shall be installed as specified on the drawings. Accessories and other items essential to complete the sheet metal installation, though not specifically indicated or specified, shall be provided. Roof flanges of sheet metal shall be set in bituminous cement over built-up roofing or shall be woven into shingle roofing before nailing. Application of bituminous strip flashing over roof flanges of various sheet metal items is covered in SECTION: BUILT-UP ROOFING. Installation of sheet metal items used in conjunction with roofing shall be coordinated with roofing work to permit continuous roofing operations. Factory-fabricated components shall be packed in cartons marked with the manufacturer’s name or trademark printed or embossed at frequent intervals permit easy identification.

1.03

SUBMITTALS:

A. Shop Drawings: Shop drawings shall be submitted for approval in accordance with the SPECIAL PROVISIONS. Materials shall not be delivered to the site until after the approved shop drawings have been returned to the contractor. Drawings shall show weights, gages, or thickness of sheet metal; type of materials; joining, expansion-joint spacing, and fabrication details; and installation procedures.

B. Samples: Samples of materials proposed for use shall be submitted for approval upon request.

1.04 DELIVERY, STORAGE, AND HANDLING: Materials shall be adequately packaged and protected during shipment and shall be inspected for damage, dampness, and wet-storage stains upon delivery to the job site. Materials shall be clearly labeled as to type and manufacturer. Sheet metal items shall be carefully handled to avoid damage. Materials shall be stored in dry, weathertight, ventilated areas until immediately before installation.

PART 2 – PRODUCTS

2.01 MATERIALS: Materials shall conform to the requirements specified below. Different items need not be of the same metal, except that if copper or copper clad stainless steel is selected for any exposed item, all exposed items shall be either copper or copper clad stainless steel.

A. Aluminum Extrusions: ASTM B 221, Alloy 6063, Temper T5.

B. Bituminous Cement: ASTM D 2822, Type I.

C. Fasteners: Fasteners shall be the best type for the application as recommended by the manufacturer.

D. Felt: ASTM D 2178, Type III or IV.

E. Plastic Hardsetting Sealant: As recommended by aluminum manufacturers.

F. Polyvinyl Chloride (PVC) Reglets: ASTM D 1784.

G. Sheet Metal:

1. Galvanized Sheet Steel: ASTM A 525, 24 Gauges, for flashing and ASTM A 527, 24 Gauges, for downspouts and gutters.

2. Copper: ASTM B 370. Temper Hol.

3. Copper Clad Stainless Steel: ASTM B 506, Type 409 core. Thickness of copper on each side shall be 10 percent of total thickness.

4. Lead-Coated Copper: ASTM B 101, Type I, Class A. Copper shall weight not less than that shown for the item designated in Table 1, before coating.

5. Stainless Steel: Corrosion-resisting steel, hereinafter referred to as “stainless steel”; ASTM A 167, Type 302 or 304; fully annealed, dead soft temper.

H. Solder: ASTM B 486, Alloy 50B, for use with copper and Alloy 60B for use with Stainless steel.

I. Slip Sheet: Fed Spec UU-B-790, Type I, Style 1b, Grade A.

J. Through-Wall Flashing, Wall Cavities less than ¾ inch.

1. Electro-sheet copper not less than 5 ounces, factory coated both sides with acid- and alkali-resistant bituminous compound not less than 6 ounces per square foot or factory covered both sides with asphalt-saturated cotton fabric, glass-fiber fabric, or with 40-pound reinforced kraft paper bonded with asphalt.

2. Electro-sheet copper completely encased by, and chemically and physically bonded to a sheet of lead, coated with asphalt mastic on both sides, bonded under pressure between two layers of asphalt-saturated woven cotton fabric or glass-fiber fabric. Total weight to be not less than 5 ounces per square foot.

3. Electro-sheet copper not less than 5 ounces, bonded to lead foil not less than 2 ounces per square foot covered both sides with asphalt mastic and bonded between 2-ply reinforced kraft paper.

4. Stainless steel, Type 304, not less than 0.003-inch thick, completely encased by and permanently bonded on both sides to 50 pound high strength bituminized crepe kraft paper, using hot asphalt, heat, and pressure.

5. Nonreinforced, waterproof, impermeable extruded elastomeric single ply sheeting not less than 30-mils thick.

6. Three ounce copper core, with 2 mils of dense, clear, polyethylene sheet bonded to each side of the copper.

7. Electro-sheet copper completely encased by and physically bonded to a sheet of lead, coated on both sides with an elastic asphalt compound.

K. Through-Wall Flashing, Wall Cavities Exceeding ¾ Inch: Flashing shall be copper, stainless steel or copper-clad stainless steel having factory-formed deformations providing mechanical bond in mortar joints. Minimum metal thickness shall be as indicated on the drawings.

L. Optional Through-Wall Flashing Materials: Other through-wall flashing material may be used for flashing if the following performance criteria are met:

1. No cracking or flaking when bent 180 degrees over a 1/32-inch mandrel and rebent at the same point over the same mandrel in an opposite direction at 0 degree C.

2. Impermeable to a hydrostatic head of 10 feet of water. Test for permeability shall be in accordance with ASTM E 96.

3. Minimum tensile strength of 40 psi when tested in accordance with ASTM D 751.

4. No visible deterioration after being subjected to a 400-hour direct weathering test in accordance with ASTM G 7 and evaluated according to ASTM D 1670 or D 2247.

5. Not affected by a 10-day exposure to 5 percent solutions of sulphuric acid, hydrochloric acid, sodium hydroxide, or saturated lime solution.

2.02 SEALANT: Sealant shall be gun grade synthetic rubber caulking, back-up sealing compound which air dries to a permanent, flexible sealant offering exceptional resistance to outdoor weathering and water. The materials shall be recognized for sealing joints between similar and dissimilar surfaces and capable of adhering to unprimed and painted metals, galvanized steel, wood, cold-rolled steel and shall be equal to No. 202 Weatherban Brand Sealant produced by “3M” Company, 3M Center 223-6NE, St Paul, Minnesota 55101, with the following properties:

Base: Synthetic Elastomer

Solvent: Aromatic

Color: White, Gray, or Aluminum

Consistency: Medium heavy paste

Solids Content: 76% (Approximate)

Application Method: Hand caulking or pressure gun application

PART 3 - EXECUTION

3.01 PROTECTION OF ALUMINUM: Aluminum shall not be used where it will be in contact with copper or where it will contact water which flows over copper surfaces. Aluminum that will be in contact with wet or pressure-treated wood, mortar, concrete, masonry, or ferrous metal shall be protected against galvanic or corrosive action by one of the following methods:

A. Paint: Aluminum surfaces to be protected shall be solvent cleaned and given a coat of zinc-chromate primer and one coat of aluminum paint. Aluminum paint shall conform to the requirements of Steel Structures Painting Council (SSPC) 101-64T, Type 1.

B. Nonabsorptive Tape or Gasket: Nonabsorptive tape or gasket shall be placed between the adjoining surfaces and shall be cemented to the aluminum surface using a cement compatible with aluminum.

3.02 SOLDERING, RIVETING, SEAMING, AND SEALING: Where soldering is specified herein it shall apply to copper, copper clad stainless steel, and stainless steel items. Where riveting and sealing are specified for aluminum it shall apply to aluminum 0.-40 inch or less in thickness. Riveting shall apply to either metal as specified.

A. Soldering: Edges of sheet metals, except lead coating materials shall be pretinned before soldering is begun. Soldering shall be done slowly with well heated soldering irons so as to thoroughly heat the seams and completely sweat the solder through the full width of the seam. Edges of lead coated material to be soldered shall be scraped or wire-brushed to produce a bright surface, and seams shall have a liberal amount of flux brushed in before soldering is begun. Edges of stainless steel to be pretinned shall be treated with soldering acid flux. Soldering shall follow immediately after application of the flux. Upon completion of soldering the acid flux residue shall be thoroughly cleaned from the sheet metal with a solution of washing soda in water and rinsed with clean water. Joints in aluminum sheets 0.040 inch or less n thickness shall be made mechanically and sealed with the sealant specified.

B. Seams: Seams shall conform to the following requirements:

1. Flat-lock seams shall finish not less than 1-inch wide.

2. Soldered-lap seams shall finish not less than 1-inch wide.

3. Unsoldered plain-lap seams shall lap not less than 3 inches unless otherwise specified.

4. Flat seams shall be made in the direction of the flow.

3.03 COVERING ON MINOR FLAT, PITCHED, OR CURVED SURFACES: Unless otherwise specified or indicated, all minor flat, pitched, or curved surfaces, such as crickets, bulkheads, dormers, and small decks, shall be covered or flashed with 18- by 24-inch metal sheets and secured with cleats. One ply of felt covered with one ply of slip sheet shall be applied as underlayment on wood surfaces. Two cleats shall be placed on the long side and one cleat shall be placed on the short side. Seams in materials other than aluminum shall be locked and soldered. Seams in aluminum shall be locked and sealed with plastic hardsetting sealing material recommended by aluminum supplier.

3.04 DOWNSPOUTS: Downspouts shall be set plumb and not less than 1 inch from the wall. Leaders shall connect gutters on overhanging eaves to downspouts. Leaders shall be set with a slope not less than 1/16-inch per foot or more than 30 degrees below a horizontal line. Leaders shall fit over the outlet tube in gutter bottom and shall fit into and be riveted to the downspout. Rivet spacing shall be not more than 2 inches. Strainers shall be set loosely in the eaves tube opening in gutter. Joints between lengths of downspouts shall be made by telescoping the end of the upper lengths at least ¾ inch into the lower length. Downspouts terminating in drainage lines shall be neatly fitted into the downspout boots and the joint filled with a portland cement mortar cap sloped away from downspout. Downspouts terminating at splash blocks or splash pans shall be provided with stock elbow-type fittings. Downspout hangers shall be provided adjacent to the joint at the top of each section of downspout except that the bottom section shall have an additional strap adjacent to the bottom joint when splash blocks or splash pans are required. Hangers shall be 1/16- by 1-inch flat stock of the same material as the downspout.

3.05 EDGE STRIP: A continuous edge strip shall be provided where indicated or specified to secure loose edges of the sheet metalwork. Butt joints shall be spaced approximately 1/8-inch apart. The strip shall be fastened to the supporting construction with nails evenly spaced not over 12 inches on centers. Where the fastening is to be made to concrete or masonry, screws shall be used and shall be driven in expansion shields set in concrete or masonry. The strip for fascia anchorage shall be installed to extend below the supporting construction to form a drip and to allow the flashing to be hooked over the lower edge at least ¾ inch. The strip shall be of sufficient width to provide adequate bearing area to insure a rigid installation. Where horizontal nailer is vented for insulation and the strip is placed over masonry or concrete, the strip shall be installed over 1/16-inch thick metal washers placed at screws. Washers shall be of metal that is electrolytically compatible with the edge strip.

3.06 EXPANSION JOINTS: Expansion joints shall be provided at 40-foot intervals for copper and stainless steel and at 32-foot intervals for aluminum, except that where the distance between the last expansion joint and the end of the continuous run is more than half the required interval spacing an additional joint shall be provided. Joints shall be evenly spaced. Extruded aluminum gravel stops and fascia shall be joined by expansion and contraction joints at not more than 12-foot spacing.

3.07 FLASHINGS: Flashings shall be installed at intersections of roof with vertical surfaces and at projections through roof. Cap flashings shall be turned around exterior corners of masonry or concrete walls at least 2 inches, shall be secured into masonry joints and into concrete with expansion anchors and sealed with No. 2 or 4 sealing compound. Cap and base for exterior and interior corners shall be factory-fabricated units. Corner units shall have mitered joints, shall be installed with 6-inch lap joint over flashings on each side. Unless otherwise indicated, through-wall flashing shall be terminated ½ inch inside each exposed face in the wall. Except as otherwise indicated, cap flashings shall be provided over base flashings. Perforations in flashings made by masonry anchors shall be covered by an application of bituminous plastic cement in the perforation. Flashing shall be installed on top of joint reinforcement.

A. Base Flashings: Base flashing shall extend out on the roof or horizontal surface not less than 4 inches. Metal base flashing shall be installed at locations indicated and shall be coordinated with roofing work. Metal base flashing shall be set in plastic bituminous cement over the roofing felts, and nailed to nailing strip and shall be secured in place on the roof side with nails spaced not more than 3 inches on centers.

B. Cap Flashing: Cap flashing shall be installed either in a reglet specified in paragraph REGLETS or shall consist of a two-piece combination unit with the receiver component built in the construction and the cap component interlocking not less than 1-1/2 inches into the receiver. The flange of the receiver component installed into masonry shall extend not less than 4 inches into the joint. Flange shall be located not less than 8 inches nor more than 16 inches above roofing not having cant strips or shall be located not less than 5 inches nor more than 13 inches above cant strip. Cap flashing shall overlap metal base flashing not less than 3 inches and when used with reglets shall extend into reglets not less than 1-1/8 inches. Where bituminous base flashings are provided, the cap flashing shall extend down as close as practicable to the top of the cant strip. Cap flashing shall be factory formed to provide spring action against the base flashing. Lower edge shall have a longitudinal V-5ype crimp or shall be folded under not less than ½-inch. Cap flashing terminations shall be sealed.

C. Stepped Flashing: Stepped flashing shall be installed where sloping roofs surfaced with shingles abut vertical surfaces. Separate pieces of base flashing shall be placed in alternated shingle courses. Each piece of base flashing shall extend out onto the roof at least 4 inches and shall be nailed to the deck. The stepped base flashing shall extend up along the wall not less than 4 inches and stop beneath the cap flashing or shall be anchored beneath wood siding in frame construction. Cap flashings shall be set in a reglet into masonry and concrete construction, and cap flashing shall lap over the flashing below not less than 3 inches. The stepped base flashing at vertical joints between the sections shall be lapped not less than 3 inches.

D. Through-Wall Flashing: Through-wall flashing includes sill, lintel, and spandrel flashing. The kind of through-wall flashing material used below the roofline is determined by the width of the wall cavity. The flashing shall be laid with a layer of mortar above and below the flashing so that the total thickness of the two layers of the mortar and flashing are the same thickness as the regular mortar joints. Flashing shall be one piece for lintels and sills.

1. Lintel flashing shall extend the full length of lintel. It shall extend through the wall one masonry course above the lintels and shall be bent down over the vertical leg of the outer steel lintel angle not less than 2 inches, or shall be applied over top of masonry and precast concrete lintels. Bed joints of lintels at control joints shall be underlaid with sheet metal bond breaker.

2. Sill flashing shall extend the full width of the sill and not less than 4 inches beyond ends of sill except at control joint where the flashing shall be terminated at the end of the sill.

E. Valley Flashing: Valley flashing shall be free from longitudinal seams and shall be of a width sufficient to extend not less than 5 inches under the roof covering on each side. The sheets shall lap not less than 8 inches in the direction of flow and shall be secured to roofing construction with cleats on each side. Cleats shall be spaced not more than 24 inches on centers. The exposed flashing shall be not less than 4 inches in width at the top and shall increase 1 inch in width for each additional 8 feet in length. Where the slope of the valley is 6 inches or less per foot, or the intersecting roofs are on different slopes, an inverted V-joint 1 inch high, shall be provided along the centerline of the valley, and the edge of the valley sheets shall extend 8 inches under the roof covering on each side.

3.08 GRAVEL STOPS AND FASCIA: Sheets shall be fabricated without longitudinal joints except where two-piece fascia are used when fascia depth exceeds 7 inches. Provision for expansion shall be provided at joints. Factory fabricated internal and external corner units with mitered joints shall be provided. Roof flange and splice plate of the gravel stop and fascia shall extend out on the roof not less than 4 inches, and shall be set in bituminous cement over the roofing felt. Roof flange shall be secured with nails spaced not greater than 3 inches on centers located within 1 inch of the outer edge of the flange. The fascia section shall not be face nailed except as specified for two-piece fascia. The upper piece of two-piece fascia is the same as specified above except that the fascia depth shall be at least 3-1/2 inches, and it shall overlap the lower fascia not less than 2 inches. The upper fascia shall be hemmed ½ inch at lower edge and shall be formed to fit tight against lower fascia. Either smooth or corrugated sheets may be used.

A. Extrusions: The extruded type of aluminum gravel stop and fascia shall be a factory fabricated, prepackaged, complete system with fastenings, of the style indicated. The system shall be installed in accordance with the manufacturer’s recommendations and the other requirements herein specified.

B. Sheets, Smooth: Gravel stops shall be installed with ½-inch space between sections. The cover plate shall be embedded in bituminous cement, nailed through the opening between the gravel stop sections and loose locked to the drip edge. The lower edge of fascia shall be hooked 3/4 inch over an edge strip and bent outward at an angle of 30 degrees.

3.09 GUTTERS: Gutter ends shall terminate at least ½ inch away from vertical surfaces. Gutter brackets and spacers shall be fastened to roof nailers by screws or deformed shank-type nails and shall interlock with or be fastened o the leading edge of gutter. Gutter spacers shall be 1/6-inch by 1-inch flat-stock of the same material as the gutter. Brackets and spacers shall be alternate at not more than 36 inches on centers. Gutters shall be hung with high points equidistant from downspouts and shall have a slope of not less than 1/16 inch per foot.

3.10 LOUVERS: Louvers shall be fabricated of aluminum or stainless steel to the dimensions indicated. Blades shall be accurately fitted and firmly secured to the frame by riveting and soldering if stainless steel and by riveting and sealing if aluminum. The edges of louver blades shall be folded or beaded for rigidity, and baffled to exclude driving rain. Louvers shall be provided with insect screens or bird screens as indicated.

3.11 REGLETS: Reglets shall be a factory fabricated product of proven design, complete with fittings and special shapes as may be required. Open-type reglets shall be filled with fiberboard or other suitable separator to prevent crushing of the slot during installation. Reglets shall be located not less than 8 inches nor more than 16 inches above roofing not having cant strips or shall be located not less than 5 inches nor more than 13 inches above cant strip. Reglet plugs shall be spaced not over 12 inches on centers and reglet grooves shall be filled with sealant. Friction or slot-type reglets shall have metal flashings inserted the full depth of slot and shall be lightly punched every 12 inches to crimp the reglet and cap flashing together.

3.12 SCUPPER LININGS: The interior of scupper openings shall be lined with sheet metal. The lining shall be formed to return not less than 1 inch against both faces of the wall or parapet with the outside edges folded under ½ inch less on the top and sides. The perimeter of the lining shall be approximately ½ inch less than the perimeter of the scupper. The top and sides of scuppers on the roof-deck side shall be joined to base flashing by a locked and soldered joint. The bottom edge shall be joined by a locked and soldered joint to the base flashing and where required, shall be formed with a ridge to act as a gravel stop around the scupper inlet. Surfaces to receive the lining shall be coated with bituminous cement.

3.13 SPLASH PANS: Splash pans shall be installed where downspouts discharge. Splash pans shall be the pre-cast concrete type of minimum dimensions 12” x 24” x 3” thick.

3.14 CONTRACTOR QUALITY CONTROL: The Contractor shall establish and maintain a quality control procedure for sheet metal used n conjunction with roofing to assure compliance of the installed sheet metalwork with the contract requirements. Any work found not to be in compliance with the contract shall be promptly removed and replaced or corrected in an approved manner. Quality control shall include, but not be limited to, the following:

A. Observation of environmental conditions; number and skill level of sheet metal workers; condition of substrate.

B. Verification of compliance of materials before, during, and after installation.

C. Inspection of sheet metalwork, for proper size and thickness, fastening and joining, and proper installation.

Procedure shall be submitted for approval prior to start of roofing work and shall include a checklist of points to be observed. The actual quality control observations and inspections shall be documented and a copy of the documentation furnished to the Contracting Officer at the end of each day.

Sheet Metal Selection Guide

Table 1

Galvanized

Lead-Coated

Detail Item

Steel Copper Copper

Counterflashings

24 gauge 16 ounce 16 ounce

Pressure bars

1- 1/4x3/16x2”

Wall Coping

16 ounce

Continuous Cleat

20 gauge 20 ounce 20 ounce

Expansion joint curb clip 1/8x8 N/A N/A

Counterflashing receiver 20 gauge 20 ounce 20 ounce

Gravel stop and fascia

24 gauge 16 ounce

Scupper, conductor head and conductor

16 ounce

Gutter

Cradle support

3/16x1 3/16x1 3/16x1

Sanitary vent pipe flashing 24 gauge 16 ounce 16 ounce

Tubular penetration flashing 24 gauge 16 ounce

Pitch Pan

16 ounce

“H” column hood

16 gauge N/A N/A

Roof drain gravel stop

N/A 16 ounce 16 ounce

NOTE: This table covers the detail conditions shown in the standard NRC/SMACCNA drawings. If project conditions result in increased sheet metal cross-sectional width, comply with applicable SMACCNA gauge, thickness and weight requirements.

* 4 lb lead and preformed neoprene are also recommended for metal and PVC pipes, respectively.

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SECTION 07600 PAGE 10