Specification_07550 _Modified_Bituminous_Roofing _GAF_System.pdf

GAF® LIBERTY™ DESIGN LINE June 5, 2014

GUIDE SPECIFICATION

SECTION 07550

MODIFIED BITUMINOUS ROOFING

USFS

Building #2208

Priest Lake Ranger Station

PREPARED BY:

GAF® Architectural Information Services

PROJECT NO: G-15059

Note: GAF® does not practice architecture or engineering. This Design Line is provided as a guide specification and is based on criteria provided to GAF®. GAF® has not observed the jobsite conditions, contract specifications, or other documents and shall not be construed in any manner to be the designer of record.

07550-

GAF® LIBERTY™ DESIGN LINE

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Rev 01/13

PART 1 GENERAL

1.01 SUMMARY

A. Section Includes

1. Asphaltic modified bituminous roofing

2. Insulation

B. Related Sections

1. Section 06100: Rough Carpentry

2. Section 07620: Sheet Metal Flashing and Trim

3. Section 15430: Plumbing Specialties

1.02 REFERENCES

A. Factory Mutual (FM Global) - Approval Guide

B. Underwriters Laboratories (UL) - Roofing Systems and Materials Guide (TGFU R1306)

C. American Society for Testing and Materials (ASTM) - Annual Book of ASTM Standards

D. Sheet Metal and Air Conditioning Contractors National Association, Inc. (SMACNA) - Architectural Sheet

Metal Manual

E. Asphalt Roofing Manufacturers Association (ARMA)

F. National Roofing Contractors Association (NRCA)

G. American Society of Civil Engineers (ASCE)

1.03 DEFINITIONS

A. Roofing Terminology: Refer to ASTM D1079 and the glossary of the National Roofing Contractors

Association (NRCA) Roofing and Waterproofing Manual for definitions of roofing terms related to this section.

1.04 PERFORMANCE REQUIREMENTS

A. Provide an installed roofing membrane and base flashing system that does not permit the passage of water, and will withstand the design pressures calculated in accordance with the most current revision of ASCE 7.

B. GAF® shall provide all primary roofing materials that are physically and chemically compatible when installed in accordance with manufacturers current application requirements.

1.05 SUBMITTALS

A. Product Data: Provide product data sheets for each type of product indicated in this section.

B. Shop Drawings: Provide manufacturers standard details and approved shop drawings for the roof system specified.

C. Samples: Provide samples of insulation(s), fasteners and roll goods for verification of quality.

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D. Certificates: Installer shall provide written documentation from the manufacturer of their authorization to install the roof system, and eligibility to obtain the warranty specified in this section.

1.06 QUALITY ASSURANCE

A. Manufacturer’s Qualifications: GAF® shall provide a roofing system that meets or exceeds all criteria listed in this section.

B. Installer’s Qualifications:

1. Installer shall be classified as a Master or Master Select contractor as defined and certified by GAF®.

C. Source Limitations: All components listed in this section shall be provided by a single manufacturer or approved by the primary roofing manufacturer.

D. Final Inspection

Manufacturer’s representative shall provide a comprehensive final inspection after completion of the roof system. All application errors must be addressed and final punch list completed.

1.07 PRE-INSTALLATION CONFERENCE

A. Prior to scheduled commencement of the roofing installation and associated work, conduct a meeting at the project site with the installer, architect, owner, GAF® representative and any other persons directly involved with the performance of the work. The installer shall record conference discussions to include decisions and agreements reached (or disagreements), and furnish copies of recorded discussions to each attending party.

The main purpose of this meeting is to review foreseeable methods and procedures related to roofing work.

1.08 REGULATORY REQUIREMENTS

A. All work shall be performed in a safe, professional manner, conforming to all federal, state and local codes.

1.09 DELIVERY, STORAGE AND HANDLING

A. Deliver all roofing materials to the site in original containers, with factory seals intact. All products are to carry either a GAF® or BMCA® label.

B. Store all pail goods in their original undamaged containers in a clean, dry location within their specified temperature range.

C. Store roll goods on end on pallets in a clean, dry, protected area. Take care to prevent damage to roll ends or edges. Do not double stack modified bitumen products.

D. Do not expose materials to moisture in any form before, during, or after delivery to the site. Reject delivery of materials that show evidence of contact with moisture.

E. Remove manufacturer supplied plastic covers from materials provided with such. Use “breathable” type covers such as canvas tarpaulins to allow venting and protection from weather and moisture. Cover and protect materials at the end of each work day. Do not remove any protective tarpaulins until immediately before the material is to be installed.

F. Materials shall be stored above 55°F (12.6°C) a minimum of 24 hours prior to application.

1.10 PROJECT CONDITIONS

A. Weather

1. Proceed with roofing only when existing and forecasted weather conditions permit.

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2. Ambient temperatures must be above 45°F (7.2°C) when applying hot asphalt or water based adhesives.

1.11 WARRANTY

A. Provide Manufacturers standard WeatherStopper® Diamond Pledge Guarantee with single source coverage* and no monetary limitation, where the manufacturer agrees to repair or replace components in the roofing system, which cause a leak due to a failure in materials or workmanship.

1. Duration: Fifteen (15) years from the date of completion.

*Materials and workmanship of listed products within this section when installed in accordance with current

GAF® application and specification requirements. Contact GAF® Contactor Services for the full terms and conditions of the guarantee.

PART 2 PRODUCTS

2.01 ACCEPTABLE MANUFACTURER

A. GAF® - 1361 Alps Road, Wayne, NJ 07470

2.02 INSULATION

A. Rigid, high-density polyisocyanurate board, with a strong white or black fibrous glass facer conforming to or exceeding the requirements of ASTM C 1289 / FS HH-I-1972. EnergyGuard HD Polyiso, with the following characteristics:

1. Board Thickness: ½”

2. Thermal Resistance (R value) of: 2.5

3. Compressive Strength: 80 psi

2.03 INSULATION ACCESSORIES

A. Cant Strip: Factory fabricated rigid perlite strip cut at angles to provide a true 45 Angle between horizontal and vertical surfaces, EnergyGuard Perlite Cant Strip, by BMCA®

B. Tapered Edge Strip: Factory fabricated rigid perlite strip cut at angles to provide a smooth transition between differences in elevation. EnergyGuard Tapered Edge Strip, by BMCA®

2.04 BASE / PLY SHEETS

A. Durable, film surfaced asphalt modified bitumen membrane containing a core glass mat coated with flexible, SBS polymer-modified asphalt, and a self adhering underside. Underside is protected with a silicone coated release film. Each roll contains two squares of material, 39.4” x 66’ (1 m x 20.1 m), 82 lbs. (37.2 kg), Liberty™ Self Adhering Base/Ply Sheet

2.05 MEMBRANE MATERIALS

A. Premium, granule surfaced asphalt modified bitumen membrane containing a core of non-woven polyester mat coated with flexible, SBS polymer-modified asphalt, and a self-adhering underside. Underside is protected with a silicone coated release film. Each roll contains one square of material, 39.4” x 34’ (1 m x 10.4 m), 94.5 lbs. (42.9 kg), Liberty™ Cap

2.06 FLASHING MATERIALS

A. Durable, film surfaced asphalt modified bitumen membrane containing a core of non-woven polyester mat coated with flexible, SBS polymer-modified asphalt, and a self adhering underside. Underside is protected

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83.7 lbs. (38 kg), Liberty™ Self Adhering Base/Ply Sheet

B. Premium, granule surfaced asphalt modified bitumen membrane containing a core of non-woven polyester mat coated with flexible, SBS polymer-modified asphalt, and a self-adhering underside. Underside is protected with a silicone coated release film. Each roll contains one square of material, 39.4” x 34’ (1 m x 10.4 m), 94.5 lbs. (42.9 kg), Liberty™ Cap

2.07 BITUMEN / ADHESIVES

A. Asphalt Primer: ASTM D 41 Leakbuster™ Matrix 307 Premium Asphalt Primer, by BMCA®

2.08 ACCESSORIES

A. Mechanical Fasteners

1. Drill•Tec Standard Roofing Fastener: Alloy steel fastener with CR-10 coating with a .220” diameter thread: Factory Mutual Standard 4470 Approved, #3 Phillips truss head or hex head.

2. Drill•Tec 3" Galvalume Plate: Galvalume, 3” (7.5 cm) diameter, center hole .25” (inch), for use with

Standard, Heavy Duty, CD-10, Fluted Nail or Toggle Bolt.

B. Standard Vents

1. A spun aluminum vent, pre-flashed with modified bitumen designed to waterproof soil pipes and roofing protrusions. The Standard MVent, by MWeld®.

NOTE: Not for use over active pipes that emit steam or excessive moisture vapor, condensation may occur. Not for use over boiler or heater/furnace vent pipes.

C. Adjustable Vents

1. A two-piece roof-flashing unit consisting of a pre-flashed spun aluminum base and a flexible upper boot, allowing for waterproofing of tall or awkward roof protrusions. The Adjustable MVent, by MWeld®.

D. Plumbing Vents

1. A pre-flashed with modified bitumen membrane and is designed to waterproof vent pipes. It can be used as a pipe cover to replace finger and cap flashing on standard vent pipe details. The Pre-Flashed Plumbing

Vent, by MWeld®.

E. Drains

1. A spun aluminum (or copper) roof drain with gravel guard, strainer cap, and waterproofing plumbing seal attached. Pre-flashed with modified bitumen and available in full and insert sizes to accommodate new construction and retrofit applications. The MDrain, by MWeld®.

2. A Pre-flashed metal through-wall roof drain designed for easy installation to aid in quick lateral removal of water. The Mscupper, by MWeld®.

F. Sealant Pans

1. A structural urethane outer shell, bonded to the roof surface, filled with a urethane rubber sealant. The urethane sealant conforms to the shape of any roof penetration through a roof surface to protect the roof system from moisture. The M-Curb and M-Thane, by MWeld®

G. Expansion Joint Covers

1. Factory fabricated assemblies used to accommodate three-dimensional joints in a roof structure. Heavy reinforced flexible cover with a flexible flame retardant foam bellows for support. Nailing flanges conform to curb irregularities. The Metalastic® Expansion Joint Cover, by BMCA®.

H. Gravel Guard

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1. Three-piece fascia system with roof flange design that creates water and wind proof seals at the building perimeter. The Gravel Guard MB, by BMCA®.

PART 3 EXECUTION

3.01 EXAMINATION

A. Verify that the surfaces and site conditions are ready to receive work.

B. Verify that the deck is supported and secured.

C. Verify that the deck is cleaned and smooth, free of depressions, waves, or projections, and properly sloped to drains, valleys, eaves, scuppers or gutters.

D. Verify that the deck surfaces are dry and free of ice or snow.

E. Verify that all roof openings, curbs, pipes, sleeves, ducts, vents or other penetrations through the roof are solidly set, and that all flashings are tapered.

3.02 SUBSTRATE PREPARATION

A. Plywood Deck

1. Plywood sheathing must be exterior grade, minimum 4 ply, and not less than 15/32” (12 mm) thick.

2. Preservatives or fire retardants used to treat the decking must be compatible with roofing materials.

3. The deck must be installed over joists that are spaced 24” (61 cm) o.c. or less.

4. The deck must be installed so that all four sides of each panel bear on and are secured to joist and cross blocking. “H” clips are not acceptable.

5. Panels must be installed with a 1/8” to 1/4” (3mm – 6mm) gap between panels and must match vertically at joints to within (1/8” (3mm).

6. Decking should be kept dry and roofed promptly after installation.

7. Light metal wall ties or other structural metal exposed on top of the wood deck shall be covered with one ply of a heavy roofing sheet, such as Stratavent Eliminator Nailable Base Sheet, extending 2”-6” (5.1 cm – 15.2 cm) beyond the metal in all directions. Nail in place before applying the base ply.

8. Tape and staple fastening systems may be used on wood decks when they comply with local building codes.

9. Attach an acceptable base sheet through flat metal caps or use nails with attached 1” (25 mm) square or round metal caps that have a minimum withdrawal resistance of 40 pounds each (178 N).

B. Recover

1. Suitable roofs for recover shall be free of dust, dirt, debris, and any contaminants that may adversely affect the performance of the new roof. Areas of substantial deck deflection or membrane imperfections shall be corrected prior to installing any new roofing.

2. For recover installations over single-ply, fluid applied, coal tar and metal roofs, contact GAF® Contractor

Services for prior approval and technical requirements.

3. Taking test cuts to verify the existing roof construction and condition. Three test cuts should be made for roofs under 100 squares and one test cut per 100 squares above the minimum amount. It is highly recommended and in certain circumstances, required that a moisture survey be made to determine the extent of wet insulation and moisture entrapment. Contract GAF® Contractor Services for more information on moisture surveys.

4. Proper drainage of the new roof system is required to eliminate ponding. Provisions must be made to insure the new roof system has proper drainage, i.e., placement of additional roof drains, use of tapered insulation, use of crickets, etc., as appropriate.

5. Existing substrates and insulation (if applicable) must be dry over the majority of the roof area. Wet or deteriorated areas of insulation and substrate must be removed and replaced with new materials. When

- 6 adhering insulation or new roofing directly to the existing roof surface, the existing roof system components must be well attached to each other and their substrate.

6. All applicable code requirements must be met for recover over an existing roofing system.

7. When Stratavent® Eliminator™ Venting Base Sheet is used as the first ply, the surface of the old smooth membrane must be primed using Matrix™ 307 Asphalt/concrete Primer and allowed to dry. Install

Stratavent® Eliminator™ Venting Base Sheet and the proper roof specification listed in this Manual.

8. GAF® does not recommend partial recover or re-roofing of a single roof area due to the potential for defects in the portion of the roof system not replaced, to damage or negatively affect the performance of the new membrane. When required by project conditions or budget considerations, GAF® requires full separation of the old and new roof areas by means of a full curb mounted expansion joint or area divider installed to provide a complete watertight seal or break between areas. Tie-in constructions, in which the old and new membranes are adhered directly to each other and stripped in are not acceptable.

3.03 INSTALLATION - GENERAL

A. Install GAF®’s Ruberoid® roofing system according to all current application requirements in addition to those listed in this section.

B. GAF® Ruberoid Specification #: RI02LC

C. When the slope of the roof is ½” per foot or greater, install all plies parallel with the slope of the roof, and install intermediate wood nailers as required for the specific roof slope. Plies must extend over ridges and nailed on 6” centers.

D. Start the application of membrane plies at the low point of the roof or at the drains, so that the flow of water is over or parallel to, but never against the laps.

3.04 INSULATION - GENERAL

A. Do not apply roof insulation or roofing until all other work trades have completed jobs that require them to traverse the deck on foot or with equipment. A vapor retarder coated lightly with asphalt may be applied to protect the inside of the structure prior to the insulation and final roofing installation. Before the application of the insulation, any damage or deterioration to the vapor retarder must be repaired.

B. Do not install wet, damaged or warped insulation boards.

C. Install insulation boards with staggered board joints in one direction (unless taping joint).

D. Install insulation boards snug. Gaps between board joints must not exceed ¼” (6 mm). All gaps in excess of

¼” (6 mm) must be filled with like insulation material.

E. Wood nailers must be 3-1/2” (8.9 cm) minimum width or 1” (25 mm) wider than metal flange. They shall be of equal thickness as the insulation with a minimum 1” (25 mm) thickness. All nailers must be securely fastened to the deck.

F. Do not kick insulation boards into place.

G. Miter and fill the edges of the insulation boards at ridges, valleys and other changes in plane to prevent open joints or irregular surfaces. Avoid breaking or crushing of the insulation at the corners.

H. Do not install insulation over old lightweight insulating concrete decks without the use of a vapor retarder.

Insulation should not be installed over new lightweight insulating concrete.

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I. Cant strips must be installed at the intersection of the roof and all walls, parapets, curbs, or transitions approaching 90°, to be flashed. They shall be approximately 4” (10.2 cm) in horizontal and 4” (10.2 cm) in vertical dimension. The face of the cant shall have an incline of not more than 45 degrees with the roof.

J. Roof tape, if required over insulation joints, must be laid evenly, smoothly and embedded in a uniform coating of hot steep asphalt with 4” (10.2 cm) end laps. Care must be taken to assure smooth application of tape, and full embedment of the tape in the asphalt.

K. Do not install any more insulation than will be completely waterproofed each day.

3.05 INSULATION

A. The insulation must be securely attached to the roof deck. A minimum FMRC 1-60 attachment is recommended. Refer to FMRC Approval Guide for FM fastening patterns. Factory Mutual requires fastener density increased in corner areas for FM 1-60 and perimeter, and corner area fastener density increases for FM

1-90 or greater. Refer to FM Loss Prevention Data Sheets 1-7, 1-28, and 1-49.

B. Use only fasteners with a minimum 3 inch (7.6 cm) stress plate when mechanically attaching insulation. Do not attach insulation with nails.

3.06 INTERPLY SHEET

A. Coiled rolls should be unrolled and allowed to relax prior to installation. Cut sheets into manageable lengths that will allow for a wrinkle and void free installation.

B. Prior to installation, clean the surface of the installed Liberty™ SBS MA Base Sheet or insulation, removing all debris, dirt, moisture and other contaminants. Repair any punctures, fishmouths, wrinkles, open seams and other defects prior to installation of succeeding courses.

C. Starting at the low point of the roof, install one ply of Liberty™ SBS Self-Adhering Base Ply lapping 3” (7.6

cm) on sides and 6” (15.2 cm) on ends. Fold the bottom half of the sheet back and remove the release film from this part of the roll. Working from the center of the sheet, carefully roll and hand press the sheet back into place over the base ply being careful to avoid wrinkles and trapped air while maintaining proper alignment. Fold the upper portion of the sheet back on itself to expose and remove the remaining release film and finish the roll. Install the upper portion of the roll working from the center of the sheet outward toward the ends. Firmly hand press the sheet to avoid wrinkles and trapped air and finish with a weighted roller over the entire sheet to insure full contact with the base sheet. All side and end laps must be staggered and offset from underlying courses a minimum of 6” (15.2 cm).

D. Interply End Lap Detail: End laps must be a minimum of 6” (15.2 cm), staggered and offset from adjacent courses a minimum of 3’ (91.4 cm). On the overlapping sheet, cut the selvage edge at a 45º angle to provide a tapered transition at the “T” joints formed by succeeding courses. See “T”-Joint Selvage Cuts drawing in paragraph 8.01 N. in the GAF® Application and Specifications Manual. Remove the release film from the underside of the overlapping sheet and form the lap without wrinkles or voids. Firmly press and roll this overlap seam with a weighted roller to complete.

E. Prior to installing succeeding coursed, apply a 3/8” bead of Matrix™ 201 SBS Flashing Cement along the top edge of each course and along the 45º angle at all selvage edge “T” joint to minimize the potential for voids, blisters or open seams. Install subsequent courses as detailed above, carefully working each sheet into the laps without wrinkles or trapped air. Firmly hand press the sheet and complete the side lap by rolling with a weighted hand roller.

3.07 CAP SHEET

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A. SBS membranes must not be applied during adverse weather or without precautionary measures in temperatures below 60ºF. Contact GAF® Contractor Services for details.

B. Installation of Liberty™ SBS Self-Adhering Cap sheet in temperatures below 60º F requires heatwelding of membrane sidelaps with a hot air welder.

C. Coiled rolls should be unrolled, placed upside down and allowed to “relax” prior to installation. Then re-roll to apply.

D. Starting at the low point of the roof install one ply of Liberty™ SBS Self-Adhering Cap sheet lapping 4” (10.2

cm) on sides and 6” (15.2 cm) on ends. Fold the bottom half of the sheet back and remove the release film from this part of the roll leaving approximately 8” (20.3 cm) at the end of the roll where it will lap the previous sheet. Working from the center of the sheet, carefully roll and hand press the sheet back into place over the interply being careful to avoid wrinkles and trapped air while maintaining proper alignment. Fold the upper portion of the sheet back on itself to expose and remove the remaining release film and finish the roll. Install the upper portion of the roll working from the center of the sheet outward toward the ends. Firmly hand press the sheet to avoid wrinkles and trapped air and finish with a weighted roller over the entire sheet to insure full contact with the underlying membrane. All side and end laps must be staggered and offset from underlying courses a minimum of 6” (15.2 cm).

E. Cap sheet end lap detail: End laps must be a minimum of 6” (15.2 cm), staggered and offset from adjacent courses a minimum of 3’ (91.4 cm). After aligning end lap, fold back the overlapping sheet and apply a 1/16”

(1.6 mm) to 1/8” (3.8 mm) thick troweling of Matrix™ 201 SBS Flashing Cement to the underlying granule surface. On the overlapping sheet, cut the selvage edge at a 45º angle to provide a tapered transition at the “T” joints formed by succeeding courses. Remove the release film from the underside of the overlapping sheet and form the lap without wrinkles or voids, pressing the sheet firmly so that a uniform bead is squeezed out at the lap edges and along the transition cut. Firmly press and roll the completed end lap with a weighted roller.

Prior to installing succeeding courses, apply a bead of Matrix™ 201 SBS Flashing Cement along the top edge of each course and along the 45º angle at all selvedge edge, “T” joints to minimize the potential for voids, blisters or open seams. Install subsequent courses as detailed above, carefully working each sheet into the laps without wrinkles or trapped air. Firmly hand press the sheet and complete the side lap by rolling with a weighted hand roller.

3.08 BITUMINOUS BASE FLASHINGS

A. Install GAF® base flashing specification 2WSASA over all cant strips, horizontal to vertical transitions, roof edges and roof penetrations. Flashings are to be secured in accordance with current GAF® application guidelines.

B. Prime all surfaces with asphalt primer, and allow adequate drying time prior to adhering flashing plies.

C. Backer plies installed over masonry or other non-nailable substrates must be cut into manageable lengths to ensure adequate adhesion to the cant strip and vertical surfaces without excessive voids. All vertical laps shall be 4” (10.2 cm). Backer plies shall extend onto the field of the roof as shown in the applicable GAF® construction detail.

D. The finished ply of base flashing shall be run vertically to provide a selvage edge that will aid in achieving proper adhesion at the 3” (7.6 cm) vertical laps. If the sheet is run horizontally, the vertical laps must be a minimum of 6” (15.2 cm) and the selvage edge must be removed from the sheet or fully covered by the counterflashing. The finished flashing ply must extend out onto the field of the roof as shown in the applicable

GAF® construction detail, and must be extended a minimum of 4” (10.2 cm) beyond the edge of the prior flashing plies. The flashing must be soundly adhered to the parapet, cant area and roof surface to result in a minimum void, non-bridging construction.

E. Base flashing heights must be a minimum of 8” (20.3 cm) and a maximum of 24” (61.0 cm) above the roofline.

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F. Use only trowel-grade modified adhesive. Apply using a trowel or wide-edged putty knife with a uniform 1/8” thickness throughout. Firmly press sheets into the adhesive, and immediately nail the top of the flashing as specified in the appropriate flashing detail.

G. Corner membrane flashings, such as “bow ties” for outside corners and “footballs” for inside corners or other membrane reinforcements are required to ensure that base flashing corners are sealed at cant areas. An alternate method of corner reinforcing is to install a smooth MB membrane reinforcement piece on the prepared corner substrate prior to final surfacing membrane. Refer to MB Flashing Details section of the

GAF® Application and Specifications Manual.

3.09 PENETRATIONS

A. Horizontal penetrations shall be flashed with M-Curbs filled with M-Thane sealant, then coated with Topcoat®

Flexseal

B. Vertical penetrations shall be flashed with Topcoat® Flashing Fabric embedded between two coats of

Topcoat® Flexseal.

3.10 SHEET METAL

A. Metal should not be used as a component of base flashing. Because of the high coefficient of expansion of sheet metals and the large temperature changes that can be experienced on a roof, sheet metal or exposed metal components must be isolated from the waterproofing components of the roofing and flashing system as efficiently as possible to prevent the metal from splitting the membranes. GAF® assumes no responsibility for damage to the roofing system caused by the movement of accessory metal.

B. When it is unavoidable to use metal in the roofing system (i.e., lead flange at drains, gravel stops), treated wood nailers and insulation stops, 1” (25 mm) wider than the metal flange, should be provided for metal flange attachment. Metal flanges must always be set on top of the roof membrane with modified trowel grade cold adhesive applied material for SBS roof systems. The metal flange is then sealed using the applicable construction detail to meet applicable guarantee requirements. Metal accessories (gravel stops, counter flashing, etc.) should be 16 oz. (0.56 mm) copper, 24 gauge (0.71 mm) galvanized or stainless steel, 2 1/2 to 4 lb (1.1-1.8 kg) lead, or 0.032” (0.81 mm) aluminum.

C. Fabricate and install all sheet metal materials as shown in applicable construction details. Refer to SMACNA

(Sheet Metal and Air Conditioning Contractors National Association, Inc.) for guidance on sheet metal treatments not addressed in this specification.

D. Clean metal and apply asphalt primer to all sheet metal surfaces that will come into contact with asphalt or other bituminous materials; allow the primer adequate time to dry.

E. Use fastener types compatible with the sheet metal type.

1. Copper or lead-coated copper: use copper or bronze fasteners.

2. Lead and galvanized steel: use galvanized or cadmium-plated sheet fasteners.

3. Aluminum: use aluminum fasteners.

4. Stainless steel: use stainless steel fasteners.

F. Metal counter-flashing shall have a minimum 4” (10.2 cm) face with a drip lip. The bottom edge of the counterflashing shall cover the roofing membrane and/or base flashing by a minimum of 4” (10.2 cm). Metal counter flashing used for masonry walls, wooden walls, or through wall metal flashings should be a two piece design to allow for installation and later removal. Metal counter-flashings for stucco, EIFS, wood siding or similar materials should be designed appropriately, such as “Z” type flashing. End joints shall be lapped 3”

(7.6 cm) or more. Adequate fasteners must be provided to secure against wind forces. Skirt fasteners shall be watertight.

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G. Metal termination bars shall be a minimum of 1/10” (3 mm) thick x 1” (25 mm) wide with preformed sealant edge lap. Bar should have 1/4” (6 mm) x 3/8” (10 mm) slotted holes on 4” (10.2 cm) centers to facilitate mechanical anchorage.

Note: Termination bars are not suitable in all base flashing and wall flashing conditions. Termination bars may only be used in conjunction with an appropriate counter-flashing extending a minimum of 4”

(10.2 cm) below the termination bar.

H. Metal flanges for gravel stops, eave strips, and pitch pockets to be used in conjunction with roofing shall be primed (both sides), set in modified trowel grade cold adhesive applied material for SBS roof systems. Flanges shall be a minimum of 3 1/2” (8.9 cm) wide for gravel stops or eave strips and 4” (10.2 cm) wide for projections and extensions through the roof. The gravel stop lip should be at least 3/4” (19 mm) high. Eave strip lips shall be at least 3/8” (10 mm) high. Provisions must be made for securing the skirt to the face of the wall. This may be a wood nailer strip for masonry and metal construction. In all cases, gravel stop and eave strip nailer should be fastened to the deck or deck system with adequate resistance against wind forces.

I. Stacks shall have metal sleeve flashing a minimum of 8” (20.3 cm) high. Pitch pockets for brackets, supports, pad-eyes, etc., shall have a 4” (10.2 cm) minimum height metal sleeve.

J. On re-roofing projects, provisions shall be made for reinstallation of existing sheet metal duct work, equipment, coping metal and counter-flashing removed in conjunction with the new work. Also, provide for cleaning and repairing of existing defective sheet metal, and replacement of missing and irreparable sheet metal to match existing types. Light gauge sheet metal flashings which are incorporated into the Ruberoid® roof system are not suitable for re-use and must be replaced with new material.

K. Conduits and piping such as electrical and gas lines must be set on wood blocking or some other form of support. Wood blocking/supports must be set on pads constructed of an additional layer of roof membrane material.

3.11 WALKWAYS

A. Walkways for normal rooftop traffic may be constructed from two plies of Liberty™ membrane. This type of walkway is not for sidewalk or patio-type use.

B. Construct walkways by solidly adhering a first ply of smooth surfaced membrane to the field of the roof followed by a granule surfaced membrane to the surface of the first ply.

C. Walkway sections should be no longer than 10’ (3 m), with a 6” (15.2 cm) minimum gap between each section to allow for drainage.

3.12 ROOF PROTECTION

A. Protect all partially and fully completed roofing work from other trades until completion.

B. Whenever possible, stage materials in such a manner that foot traffic is minimized over completed roof areas.

C. When it is not possible to stage materials away from locations where partial or complete installation has taken place, temporary walkways and platforms shall be installed in order to protect all completed roof areas from traffic and point loading during the application process.

D. Temporary tie-ins shall be installed at the end of each workday and removed prior to commencement of work the following day.

3.13 CLEAN-UP

A. All work areas are to be kept clean, clear and free of debris at all times.

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B. Do not allow trash, waste, or debris to collect on the roof. These items shall be removed from the roof on a daily basis.

C. All tools and unused materials must be collected at the end of each workday and stored properly off of the finished roof surface and protected from exposure to the elements.

D. Dispose of or recycle all trash and excess material in a manner conforming to current EPA regulations and local laws.

E. Properly clean the finished roof surface after completion, and make sure the drains and gutters are not clogged.

F. Clean and restore all damaged surfaces to their original condition.

END OF SECTION