UFGS_07_51_13_EDITED_(002).pdf

SECTION 07 51 13 Page 1

SECTION TABLE OF CONTENTS

DIVISION 07 - THERMAL AND MOISTURE PROTECTION

SECTION 07 51 13

BUILT-UP ASPHALT ROOFING

05/12

PART 1 GENERAL

1.1 REFERENCES

1.2 DESCRIPTION OF ROOF MEMBRANE SYSTEM[S]

1.5 DELIVERY, STORAGE, AND HANDLING

1.5.1 Delivery

1.5.2 Storage

1.5.3 Handling

1.6 ENVIRONMENTAL CONDITIONS

1.7 SEQUENCING

1.8 WARRANTY

1.8.1 Roof Membrane Manufacturer Warranty

1.8.2 Roofing System Installer Warranty

1.9 CONFORMANCE AND COMPATIBILITY

PART 2 PRODUCTS

2.1 GENERAL

2.2 FIBERGLASS FELT MATERIALS

2.3 BASE FLASHING MEMBRANE

2.4 ASPHALT

2.5 SURFACING MATERIAL

2.5.1 Aggregate for Surfacing Built-up Roofing

2.6 PRIMER

2.7 ASPHALT ROOF CEMENT

2.8 CANT STRIPS

2.9 UNSATURATED FELT OR ROSIN-SIZED BUILDING PAPER

2.10 FASTENERS AND PLATES

2.10.1 Wood Substrates and Nailers

2.10.2 Masonry or Concrete Walls and Vertical Surfaces

2.10.3 Metal Plates

2.11 PRE-MANUFACTURED ACCESSORIES

2.11.1 Pre-fabricated Curbs

2.12 WALKPADS

2.12.1 ROOF WALKWAYS

2.14 ROOF INSULATION BELOW MEMBRANE SYSTEM

PART 3 EXECUTION

3.1 VERIFICATION OF CONDITIONS

3.2 PREPARATION

3.2.1 Protection of Property

3.2.1.1 Protective Coverings

3.2.1.2 Bitumen Stops

3.2.2 Equipment

SECTION 07 51 13 Page 2

3.2.2.1 Mechanical Application Devices

3.2.2.2 Flame-Heated Equipment

3.2.2.3 Open Flame Application Equipment

3.2.3 Priming of Surfaces

3.2.3.1 Priming of Concrete and Masonry Surfaces

3.2.3.2 Priming of Metal Surfaces

3.2.4 Covering of Wood Substrate

3.2.5 Heating of Asphalt

3.2.5.1 Temperature Limitations for Asphalt

3.3 APPLICATION

3.3.1 Phased Membrane Construction

3.3.2 Temporary Roofing and Flashing

3.3.2.1 Removal

3.3.3 Base Sheet Application - General

3.3.3.1 Ventilating Base Sheets

3.3.4 Ply Felts

3.3.4.1 Hot-Mopping of Ply Felts

3.3.4.2 Backnailing of Ply Felts

3.3.4.3 Valleys and Ridges

3.3.5 Membrane Flashing

3.3.5.1 Strip Flashing

3.3.5.2 Membrane Flashing at Roof Drain

3.3.5.3 Pre-fabricated Curbs

3.3.5.4 Set-On Accessories

3.3.5.5 Lightning Protection

3.3.6 Roof Walkpads

3.3.7 Elevated Metal [Walkways] [and] [Platforms]

3.3.9 Aggregate Surfacing

3.3.11 Correction of Deficiencies

3.3.12 Clean Up

3.4 PROTECTION OF APPLIED ROOFING

3.4.1 Protection Against Moisture Absorption

3.4.2 Water Cutoffs

3.4.3 Temporary Flashing for Permanent Roofing

3.4.4 Temporary Walkways, Runways, and Platforms

3.4.5 Glaze Coat

3.5 FIELD QUALITY CONTROL

3.5.1 Test for Surface Dryness

3.5.2 Construction Monitoring

-- End of Section Table of Contents --

SECTION 07 51 13 Page 3

USACE / NAVFAC / AFCEC / NASA UFGS-07 51 13 (May 2012)

Change 2 - 11/18

Preparing Activity: NAVFAC Superseding UFGS-07 51 13 (February 2012)

UNIFIED FACILITIES GUIDE SPECIFICATIONS

References are in agreement with UMRL dated April 2019

SECTION 07 51 13

BUILT-UP ASPHALT ROOFING

05/12

PART 1 GENERAL

1.1 REFERENCES

The publications listed below form a part of this specification to the extent referenced. The publications are referred to within the text by the basic designation only.

AMERICAN SOCIETY OF CIVIL ENGINEERS (ASCE)

ASCE 7 (2017) Minimum Design Loads for Buildings and Other Structures

ASTM INTERNATIONAL (ASTM)

ASTM C1153 (2010) Standard Practice for Location of

Wet Insulation in Roofing Systems Using

Infrared Imaging

ASTM C208 (2012; R 2017; E 2017) Standard

Specification for Cellulosic Fiber

Insulating Board

ASTM C728 (2017a) Standard Specification for Perlite

Thermal Insulation Board

ASTM D1863/D1863M (2005; R 2011; E 2012) Mineral Aggregate

Used on Built-Up Roofs

ASTM D1864/D1864M (1989; E 2009; R 2009) Moisture in Mineral

Aggregate Used on Built-Up Roofs

ASTM D1970/D1970M (2018) Standard Specification for

Self-Adhering Polymer Modified Bituminous

Sheet Materials Used as Steep Roofing

Underlayment for Ice Dam Protection

ASTM D2170/D2170M (2018) Standard Test Method for Kinematic

Viscosity of Asphalts (Bitumens)

ASTM D2178/D2178M (2015a) Asphalt Glass Felt Used in Roofing

SECTION 07 51 13 Page 4 and Waterproofing

ASTM D312/D312M (2016a) Standard Specification for Asphalt

Used in Roofing

ASTM D3617 (2007; R 2015; E 2015) Sampling and

Analysis of New Built-Up Roof Membranes

ASTM D41/D41M (2011; R 2016) Standard Specification for

Asphalt Primer Used in Roofing, Dampproofing, and Waterproofing

ASTM D4263 (1983; R 2012) Standard Test Method for

Indicating Moisture in Concrete by the

Plastic Sheet Method

ASTM D4402/D4402M (2015) Viscosity Determination of Asphalt at Elevated Temperatures Using a

Rotational Viscometer

ASTM D448 (2012; R 2017) Standard Classification for

Sizes of Aggregate for Road and Bridge

Construction

ASTM D4586/D4586M (2007; E 2012; R 2012) Asphalt Roof

Cement, Asbestos-Free

ASTM D4601/D4601M (2004; R 2012) Asphalt-Coated Glass Fiber

Base Sheet Used in Roofing

ASTM D4637/D4637M (2015) EPDM Sheet Used in Single-Ply Roof

Membrane

ASTM D4869/D4869M (2016a) Standard Specification for

Asphalt-Saturated Organic Felt

Underlayment Used in Steep Slope Roofing

ASTM D4897/D4897M (2016) Standard Specification for

Asphalt-Coated Glass-Fiber Venting Base

Sheet Used in Roofing

ASTM D517 (1998; R 2008) Asphalt Plank

ASTM D6162/D6162M (2016) Standard Specification for Styrene

Butadiene Styrene (SBS) Modified

Bituminous Sheet Materials Using a

Combination of Polyester and Glass Fiber

Reinforcements

ASTM D6163/D6163M (2016) Standard Specification for Styrene

Bituminous Sheet Materials Using Glass

Fiber Reinforcements

ASTM D6164/D6164M (2016) Standard Specification for Styrene

Bituminous Sheet Materials Using Polyester

Reinforcements

ASTM D6757/D6757M (2018) Standard Specification for

Underlayment Felt Containing Inorganic

SECTION 07 51 13 Page 5

Fibers Used in Steep-Slope Roofing

ASTM E108 (2011) Fire Tests of Roof Coverings

FM GLOBAL (FM)

FM 4470 (2010) Single-Ply, Polymer-Modified

Bitumen Sheet, Built-up Roof (BUR), and

Liquid Applied Roof Assemblies for Use in

Class 1 and Noncombustible Roof Deck

Construction

FM APP GUIDE (updated on-line) Approval Guide http://www.approvalguide.com/

NATIONAL ROOFING CONTRACTORS ASSOCIATION (NRCA)

NRCA RoofMan (2017) The NRCA Roofing Manual

SINGLE PLY ROOFING INDUSTRY (SPRI)

ANSI/SPRI RD-1 (2014) Performance Standard for Retrofit

Drains

U.S. DEPARTMENT OF ENERGY (DOE)

Energy Star (1992; R 2006) Energy Star Energy

Efficiency Labeling System (FEMP)

UNDERWRITERS LABORATORIES (UL)

UL 790 (2004; Reprint Jul 2014) Standard Test

Methods for Fire Tests of Roof Coverings

UL RMSD (2012) Roofing Materials and Systems

Directory

1.2 DESCRIPTION OF ROOF MEMBRANE SYSTEM[S]

Asphalt applied, four-ply felt, aggregate surfaced built-up roof membrane system.

1.2.1 Qualifications of Applicator

The roofing system applicator must be approved, authorized, or licensed in writing by the roofing system manufacturer and must have a minimum of 3 years experience as an approved, authorized, or licensed applicator with the manufacturer and be approved at a level capable of providing the specified warranty.

1.4 Fire Resistance

Complete roof covering assembly must:

a. Be Class A rated in accordance with ASTM E108 , FM 4470, or UL 790; and

1.5 DELIVERY, STORAGE, AND HANDLING

1.5.1 Delivery

http://www.approvalguide.com/

SECTION 07 51 13 Page 6

Deliver materials in manufacturers' original unopened containers and rolls with manufacturer's labels intact and legible. Mark and remove wet or damaged materials from site. Where materials are covered by a referenced specification, container must bear specification number, type, and class, as applicable. Indicate on labels or bill of lading for roofing asphalt the asphalt type, finished blowing temperature (FBT), flash point (FP), and equiviscous temperature (EVT), that is, the temperature at which the viscosity is either 125 centistokes when tested in accordance with

ASTM D2170/D2170M or 75 centipoise when tested in accordance with

ASTM D4402/D4402M. Deliver materials in sufficient quantity to allow work to proceed without interruption.

1.5.2 Storage

Protect materials against moisture absorption, contamination, or other damage. Avoid crushing or crinkling of roll materials. Store roll materials on end on clean raised platforms in dry locations in enclosed buildings or trailers with adequate ventilation. Do not store roll materials in buildings under construction until concrete, mortar, and plaster work are finished and dry. Do not store materials outdoors unless approved by the Contracting Officer. Completely cover felts stored outdoors, on and off roof, with waterproof canvas protective covering. Do not use polyethylene sheet as a covering. Tie covering securely to pallets to make completely weatherproof and yet provide sufficient ventilation to prevent condensation. Maintain roll materials at temperature above 10 degrees C 50 degrees F for a 24-hour period immediately prior to application. Keep aggregate dry as defined by ASTM D1863/D1863M. Place only those materials to be used during one day's work on the roof at one time. Remove unused materials from the roof at the end of each day's work.

Immediately remove wet, contaminated or otherwise damaged or unsuitable materials from the site. Damaged materials may be marked by the

Contracting Officer.

1.5.3 Handling

Prevent damage to edges and ends of roll materials. Do not install damaged materials in the work. Select and operate material handling equipment so as not to damage materials or applied roofing.

1.6 ENVIRONMENTAL CONDITIONS

Do not install roofing during precipitation, or fog, or when air temperature is below 4 degrees C 40 degrees F, or when there is ice, frost, moisture or visible dampness on roof deck.[ Restriction on application of roofing materials below 4 degrees C 40 degrees F may be waived if

Contractor devises a means, satisfactory to Contracting Officer, of: (1) maintaining surrounding temperature above 4 degrees C 40 degrees F; (2) maintaining application temperature of heated materials without exceeding maximum specified heating temperature; and follows other recommendations of the membrane manufacturer for application in cold weather conditions.

1.7 SEQUENCING

Coordinate the work with other trades to ensure that components which are to be secured to or stripped into the roofing system are available and that permanent flashing and counterflashing are installed as the work progresses. Ensure temporary protection measures are in place to preclude moisture intrusion or damage to installed materials.[ Install roofing immediately following application of insulation as a continuous operation.

Coordinate roofing operations with insulation work so that all roof insulation applied each day is covered with complete felt ply installation

SECTION 07 51 13 Page 7 the same day.]

1.8 WARRANTY

1.8.1 Roofing System Installer Warranty

The roof system installer must warrant for a minimum period of one year that the roof system, as installed, is free from defects in installation workmanship, to include the roof membrane, flashing, insulation, accessories, attachments, and sheet metal installation integral to a complete watertight roof system assembly. Write the warranty directly to the Government. The roof system installer is responsible for correction of defective workmanship and replacement of damaged or affected materials.

The roof system installer is responsible for all costs associated with the repair or replacement work.

1.8.2 Continuance of Warranty

Approve repair or replacement work that becomes necessary within the warranty period and accomplished in a manner so as to restore the integrity of the roof system assembly and validity of the roof membrane manufacturer warranty for the remainder of the manufacturer warranty period.

1.9 CONFORMANCE AND COMPATIBILITY

Provide the entire roofing and flashing system in accordance with specified and indicated requirements, including fire and wind resistance requirements. Work not specifically addressed and any deviation from specified requirements must be in general accordance with recommendations of the NRCA RoofMan, membrane manufacturer published recommendations and details, and compatible with surrounding components and construction.

Submit any deviation from specified or indicated requirements to the

Contracting Officer for approval prior to installation.

PART 2 PRODUCTS

2.1 GENERAL

Furnish a combination of specified materials that comprise the membrane manufacturer's standard system of the number and type of plies specified.

Provide materials approved by the roof membrane manufacturer and suitable for the service and climatic conditions of the installation.

2.2 FIBERGLASS FELT MATERIALS

Perforated venting base sheet option should only be used for application directly on concrete deck.

Base sheets with perforations are rolled into place and then top mopped with hot asphalt. Base sheets without perforations are mechanically attached to nailable substrates.

a. Venting Base Sheet: ASTM D4897/D4897M, Type II, [without][with] perforations and as approved by the roof membrane manufacturer.

SECTION 07 51 13 Page 8

b. Ply Felt: ASTM D2178/D2178M, as approved by roof membrane manufacturer.

2.3 BASE FLASHING MEMBRANE

ASTM D6163/D6163M. Membrane manufacturer's standard, minimum two-ply modified bitumen membrane flashing system compatible with the built-up roof membrane and as recommended in membrane manufacturer's published literature. Provide a minimum base ply of flashing membrane of 1.8 mm 70 mils thick. Provide a minimum granule surface modified bitumen flashing cap sheet of 3 mm 120 mils thick on the selvage edge.

2.4 ASPHALT

NOTE: Asphalt type based on roof slope.

Adhere to the following general requirements:

Roof Slope, mm/m in./ft Type Asphalt

Less than 25 Less than 1/2 Type II, Type III in hot climate

25 to 50 1/2 to 1 Type III

50 to 75 1 to 1-1/2 Type III, climate

Type IV in hot

In locations where ambient temperature frequently exceeds 38 degrees C 100 degrees F and roof slope is

15 mm 1/2 inch per foot or greater, specify Type IV asphalt.

ASTM D312/D312M, Type [II] [or] [III] [or] [IV], in accordance with membrane manufacturer requirements and compatible with the slope conditions of the installation.

2.5 SURFACING MATERIAL

NOTE: Do not use coral as a gravel surface in humid locations or project locations with Environmental

Severity Classifications (ESC) of C3 thru C5. Coral usually blackens with algae and deteriorates, becoming a growth medium for sprouting seeds. Humid locations are those in ASHRAE climate zones 0A, 1A, 2A, 3A, 3C, 4C and 5C (as identified in ASHRAE

90.1). See UFC 1-200-01 for determination of ESC for project locations.

2.5.1 Aggregate for Surfacing Built-up Roofing

Water-worn gravel, crushed stone, or crushed slag, conforming to

ASTM D1863/D1863M, or marble, expanded slag, or expanded shale, conforming to ASTM D1863/D1863M except density not less than 880 kg per cubic meter 55 pcf. Aggregate conforming to gradation sizes No. 6, No. 7, and No. 67 in conformance with ASTM D448 is acceptable provided other requirements of

ASTM D1863/D1863M are met. Provide 2 percent maximum moisture content as

SECTION 07 51 13 Page 9 determined by ASTM D1864/D1864M. Provide light colored and opaque aggregate. Limestone, volcanic rock, crushed shells, and cinders are prohibited.

2.6 PRIMER

ASTM D41/D41M for asphalt roofing systems and as approved by the membrane manufacturer.

2.7 ASPHALT ROOF CEMENT

ASTM D4586/D4586M for use with asphalt roofing systems, Type II for vertical surfaces and built-up bituminous flashings; Type I for horizontal surfaces and as recommended by the membrane manufacturer.

2.8 CANT STRIPS

NOTE: Use wood cant in non-supported flashing and wood blocking details (i.e., expansion joints, area dividers, and wall/roof intersections where roof deck is not supported by a wall).

Provide standard perlite cant strips conforming to ASTM C728[ or wood fiber conforming to ASTM C208] treated with bituminous impregnation, sizing, or waxing and fabricated to provide maximum 45 degree change in direction of membrane. Provide minimum 38 mm 1-1/2 inch thick cant strips and provide for minimum 125 mm 5 inch face and 89 mm 3-1/2 inch vertical height when installed at 45 degree face angle, except where clearance restricts height to lesser dimension.

2.9 UNSATURATED FELT OR ROSIN-SIZED BUILDING PAPER

NOTE: Include requirement for unsaturated felt or rosin-sized building paper under base sheet on wood decks substrates to prevent bitumen drippage through deck joints.

Provide rosin-sized sheathing paper weighing minimum 3 kilogram per 10 square meter 5 pounds per 100 square feet or unsaturated felt weighing approximately 3.7 kilogram per 10 square meter 7-1/2 pounds per 100 square feet.

2.10 FASTENERS AND PLATES

Coated, corrosion resistant fasteners compatible with components being attached and contact surfaces. Conform to FM 4470 for fasteners for attachment to deck substrate of Class I roof deck construction and

FM APP GUIDE for the wind resistance specified. Use hard copper fasteners in contact with copper; aluminum or stainless steel fasteners in contact with aluminum; and stainless steel fasteners in contact with stainless steel. For fastening only roofing felts, use fasteners driven through metal discs, or one-piece composite fasteners with heads not less than 25 mm

1 inch in diameter or 25 mm 1 inch square with rounded or 45-degree tapered corners.

2.10.1 Wood Substrates and Nailers

SECTION 07 51 13 Page 10

Provide 11 gage annular threaded shank nails with 7/16 to 5/8 inch diameter heads; or one-piece composite nails with annular threaded shanks not less than 11 gage for securing felts and metal items. Provide fasteners long enough to penetrate minimum 25 mm 1 inch into or minimum 6 mm 1/4 inch through wood substrate materials. Do not penetrate wood decking exposed to view on the underside.

2.10.2 Masonry or Concrete Walls and Vertical Surfaces

Provide hardened steel screws with flat heads, diamond shaped points, and mechanically deformed shanks not less than 25 mm 1 inch long for securing felts, metal items, and accessories. Use power-driven fasteners only when approved in writing by Contracting Officer.

2.10.3 Metal Plates

Flat corrosion-resistant round stress plates as recommended by the modified bitumen sheet manufacturer's printed instructions and meeting the requirements of FM 4470; minimum 50 mm 2 inch in diameter. Form discs to prevent dishing or cupping.

2.11 PRE-MANUFACTURED ACCESSORIES

Pre-manufactured accessories must be manufacturer's standard for intended purpose, compatible with the membrane roof system and approved for use by the roof membrane manufacturer.

2.11.1 Pre-fabricated Curbs

Provide minimum 18 gauge G90 galvanized curbs with minimum 100 mm 4 inch flange for attachment to roof nailers. Provide minimum height of 250 mm

10 inch above the finished roof membrane surface.

2.12 WALKPADS

NOTE: Use walkpads or walkways at roof access points and where the roof or areas of the roof are intended to bear foot traffic for maintenance or other purposes once a month or more frequently.

2.12.1 ROOF WALKWAYS

Provide 950 by 1830 millimeter by 15 millimeter 36 by 72 inch by 1/2 inch thick asphalt planks, consisting of a homogeneous core of asphalt, plasticizers, and fillers bonded between two saturated and coated facing sheets. Top side must be surfaced with ceramic granules. Conform to

ASTM D517, mineral-surfaced asphalt.

2.14 ROOF INSULATION BELOW MEMBRANE SYSTEM

Provide insulation compatible with the roof membrane, approved by the membrane manufacturer.

PART 3 EXECUTION

SECTION 07 51 13 Page 11

3.1 VERIFICATION OF CONDITIONS

Before applying roofing materials, ensure that the following exist:

a. Do not install items that show visual evidence of biological growth.

b. [Drains,] [curbs,] [cants,] [control joints,] [expansion joints,]

[perimeter walls,] [roof penetrating components,] [and] [equipment supports] are in place.

c. Surfaces are rigid, clean, dry, smooth, and free of cracks, holes, and sharp changes in elevation. Joints in substrate are sealed to prevent drippage of bitumen into building or down exterior walls. Inspect surfaces and approve immediately before application of roofing and flashings. Apply the roofing and flashings to a smooth and firm surface free from ice, frost, visible moisture, dirt, projections, and foreign materials.

d. The plane of the substrate does not vary more than 6 mm 1/4 inch within an area 3 by 3 meters 10 by 10 feet when checked with a 3 meter 10 foot straight edge placed anywhere on the substrate.

e. Substrate is sloped as indicated to provide drainage.

f. Walls and vertical surfaces are constructed to receive counterflashing and will permit mechanical fastening of the base flashing materials.

g. Treated wood nailers are in place on non-nailable surfaces, to permit nailing of base flashing at minimum height of 8 inch above finished roofing surface.

h. Treated wood nailers are fastened in place at eaves, gable ends, openings, and intersections with vertical surfaces for securing of felts, edging strips, attachment flanges of sheet metal, and roof fixtures.[ Embedded nailers are flush with deck surfaces.][

Surface-applied nailers are same thickness as roof insulation.]

NOTE: Wood cants should also be used where there are non-wall supported flashings at wood blocking forming area dividers and expansion joints, and at wall and roof intersections where roof deck is not supported on wall.

i. Cants are securely fastened in place in the angles formed by walls and other vertical surfaces. The angle of the cant is approximately 45 degrees and the height of the vertical leg is not less than nominal 89 mm 3-1/2 inch. Lay cants in a solid asphalt mopping or coat of asphalt cement just prior to laying the roofing plies.

NOTE: Include venting provision for wet fill substrate materials like lightweight cellular concrete.

j. Venting is provided in accordance with the following:

SECTION 07 51 13 Page 12

(1) Edge Venting: Perimeter nailers are kerfed across width of the nailers to permit escape of gaseous pressure at roof edges.

(2) Underside Venting: Vent openings are provided in steel form decking for cast-in-place concrete substrate.

k. Exposed nail heads in wood substrates are properly set. Warped and split [boards][sheets] have been replaced. There are no cracks or end joints 6 mm 1/4 inch in width or greater. Knot holes are covered with sheet metal and nailed in place. [Wood][Plywood] decks are covered with rosin paper or unsaturated felt prior to base sheet or roof membrane application.[ Joints in plywood substrates are taped with 50 mm 2 inch wide masking tape to prevent air leakage from the underside.]

l. Insulation boards are installed smoothly and evenly, and are not broken, cracked, or curled. There are no gaps in insulation board joints exceeding 6 mm 1/4 inch in width. Insulation is being roofed over on the same day the insulation is installed.

m. [Cast-in-place concrete substrates have been allowed to cure and the surface dryness requirements specified under paragraph FIELD QUALITY

CONTROL have been met. ]No viable moisture present when conducting

ASTM D4263.

n. [Joints between precast concrete deck units, including weld plates, are grouted, leveled, and covered with 4 inch wide ply felt or other bituminous stripping membrane set in bituminous cement prior to applying other roofing materials over the area. ]Prior to application of primer on precast concrete decks, cover joints with a minimum 100 mm

4 inch strip of felt or bituminous stripping membrane set in bituminous cement.

3.2 PREPARATION

Verify that work of other trades that penetrates the roof deck or requires men and equipment to traverse the roof deck is complete.

Examine deck surfaces for inadequate anchorage, foreign material, moisture, and unevenness which would prevent the execution and quality of application.

Proceed with the roofing application only after defects have been corrected.

Starting work designates acceptance of the surfaces by the Contractor.

3.2.1 Protection of Property

3.2.1.1 Protective Coverings

Install protective coverings at paving and building walls adjacent to hoists and kettles prior to starting the work. Lap protective coverings not less than six inch, secure against wind, and vent to prevent collection of moisture on covered surfaces.Keep protective coverings in place for the duration of the roofing work.

3.2.1.2 Bitumen Stops

Provide felt bitumen stops or other means to prevent bitumen drippage at roof edges, openings, and vertical projections before hot mopped application of the roofing membrane. Form felt bitumen stops with two 300

SECTION 07 51 13 Page 13 mm 12 inch wide strips of organic ply felt. Laminate with and set strips into a coating of asphalt roof cement with one-half of the width overhanging the edge of the roof or opening. Where nailers are provided, nail the strips with roofing nails spaced 300 mm 12 inch on center in addition to embedding in asphalt roof cement. Protect the free portion of each strip from damage throughout the roofing period. After the plies of felt are in place, fold free portion of the strips back over the roofing membrane and embed in a continuous coating of asphalt roof cement. Secure with roofing nails spaced 75 mm 3 inch on center.

3.2.2 Equipment

3.2.2.1 Mechanical Application Devices

Provide and maintain mechanical application devices with pneumatic tires that operate without damaging the insulation, roofing membrane, or structural components.

3.2.2.2 Flame-Heated Equipment

Do not place flame-heated equipment on roof. Provide and maintain a fire extinguisher adjacent to flame-heated equipment and on the roof.

3.2.2.3 Open Flame Application Equipment

Use only open flame equipment recommended by the roofing materials manufacturer. Do not ignite open flame equipment when left unattended.

Provide and maintain a fire extinguisher adjacent to open flame equipment on the roof.

3.2.3 Priming of Surfaces

Prime all surfaces to be in contact with adhered membrane materials. Apply primer at the rate of 3 liters per 10 sq. meters 0.75 gallon per 100 sq. ft.

or as recommended by roof membrane manufacturer's printed instructions to promote adhesion of membrane materials. Allow primer to dry prior to application of membrane materials to primed surface. Avoid flammable primer material conditions in torch applied membrane base flashing applications.

3.2.3.1 Priming of Concrete and Masonry Surfaces

After surface dryness requirements have been met, coat concrete and masonry surfaces which are to receive roofing and base flashing uniformly with primer. Allow primer to dry before application of roofing and flashing materials.

3.2.3.2 Priming of Metal Surfaces

Prime flanges of metal components to be embedded into the roofing system prior to setting in bituminous materials or stripping into roofing system.

3.2.4 Covering of Wood Substrate

Cover wood substrate with a layer of unsaturated felt or rosin-sized building paper lapped 50 mm 2 inch at sides and 100 mm 4 inch at ends.

Nail to hold in place prior to application of roofing system.

3.2.5 Heating of Asphalt

Break up solid asphalt on a surface free of dirt and debris. Heat asphalt

SECTION 07 51 13 Page 14 in kettle designed to prevent contact of flame with surfaces in contact with the asphalt. Provide visible working thermometer and thermostatic controls set to the temperature limits. Keep controls in working order and calibrated. Use immersion thermometer, accurate within a tolerance of plus or minus one degree C 2 degrees F, to check temperatures of the asphalt frequently. When temperatures exceed maximum specified, remove asphalt from the site. Do not permit cutting back, adulterating, or fluxing of

3.2.5.1 Temperature Limitations for Asphalt

Heat and apply asphalt at the temperatures specified below unless specified otherwise by manufacturer's printed application instructions. Use thermometer to check temperature during heating and application. Have kettle attended constantly during heating process to ensure specified temperatures are maintained. Do not heat asphalt above its finished blowing temperature (FBT). Do not heat asphalt between 260 and 274 degrees

C 500 and 525 degrees F for longer than four consecutive hours. Do not heat asphalt to the flash point (FP). Apply asphalt and embed membrane sheets when temperature of asphalt is within plus or minus 14 degrees C 25 degrees F of the equiviscous temperature (EVT). Before heating and application of asphalt refer to the asphalt manufacturer's label or bill of lading for FP, FBT, and EVT of the asphalt used.

3.3 APPLICATION

Apply roofing materials as specified unless approved otherwise by the

Contracting Officer. Keep roofing materials dry before and during application. Except for aggregate surfacing, complete application of roofing in a continuous operation. Begin and apply only as much roofing in one day as can be completed that same day. Maintain specified temperature for asphalt. [Provide temporary roofing and flashing as specified herein prior to application of permanent roofing system.] Do not apply aggregate surfacing until the other roofing application procedures specified herein are completed.

3.3.1 Phased Membrane Construction

Phased application of membrane plies is prohibited.

3.3.2 Temporary Roofing and Flashing

Provide watertight temporary roofing and flashing where considerable work by other trades, such as installing [cooling towers,] [antennas,] [pipes,]

[ducts,] is to be performed on the roof or where construction scheduling or weather conditions require protection of building interior before permanent roofing system can be installed. Do not install temporary roofing over permanently installed insulation. Provide rigid pads for traffic over temporary roofing.

3.3.2.1 Removal

Completely remove temporary roofing and flashing before continuing with application of permanent roofing system.

3.3.3 Base Sheet Application - General

Mechanically fastened base sheets are required when uninsulated roof membrane system is to be applied

SECTION 07 51 13 Page 15 directly to nailable decks, excluding steel deck.

Ventilating base sheet is required when roof membrane is applied directly to wet fill deck materials like lightweight insulating or cellular concrete and gypsum fill, and when applied over new poured concrete decks.

Apply base sheets at right angles to roof slope, except on insulated roofs where nailers (insulation

SECTION 07 51 13 Page 16 stops) have been applied at right angles to slope and on decks sloped 1:12 25 mm per meter 1 inch per foot or more, apply felts parallel to roof slope.

Include requirements for applying felts to barrel-type roofs only when applicable.

Fully adhere base sheets in accordance with membrane manufacturer's printed instructions. Roll and broom in the base sheet to ensure full contract with the hot asphalt application. On nailable substrates, mechanically fasten base sheet in conformance with specified wind resistance requirements and membrane manufacturer's printed instructions, and to include increased fastening frequency in corner and perimeter areas. Drive fasteners flush with no dishing or cupping of fastener plate. Where applicable, base sheet may be mechanically fastened in conjunction with insulation to the substrate, in accordance with membrane manufacturers printed instructions. Apply sheets in a continuous operation. Apply sheets with side laps at a minimum of 50 mm 2 inch unless greater side lap is recommended by the manufacturer's standard written application instructions.Provide end laps of not less than 150 mm 6 inch and staggered a minimum of 1 meter 36 inch. Apply sheets at right angles to the roof slope so that the direction of water flow is over and not against the laps].

Apply sheets on the other side in the same manner, resulting in twice the normal amount of roofing sheets and asphalt at the crown]. Extend base sheets approximately 50 mm 2 inch above the top of cant strips at vertical surfaces and to the top of cant strips elsewhere. Trim base sheet to a neat fit around vent pipes, roof drains, and other projections through the roof. Retrofit roof drains must conform to ANSI/SPRI RD-1. Application must be free of ridges, wrinkles, and buckles.

3.3.3.1 Ventilating Base Sheets

Where rigid roof insulation is a component of the roof system, specify ventilating base sheet in the appropriate roof insulation section.

Apply ventilating base sheet material as specified and recommended by the roof membrane manufacturer. Extend sheets over roof cants, up vertical surfaces, and terminate under cap flashing; at roof edges terminate sheets under outside edge of perimeter edge nailers or under gravel stop.Top mop perforated ventilating base sheet with a full, continuous mopping of hot

3.3.4 Ply Felts

Ensure proper alignment of felts prior to installation. [Apply ply felts shingle fashion perpendicular to slope of roof, including application on areas of tapered insulation that change slope direction. Apply felts on other side in same manner, resulting in twice normal amount of roofing felts and asphalt at crown]. Bucking or backwater laps are prohibited.

Apply felts in a continuous operation. Provide starter sheets of felt to maintain the specified number of plies throughout the roofing. Apply felts with side laps in accordance with the material manufacturer's printed instructions for the number of plies to be installed and in uniform alignment. Lap ends not less than 150 mm 6 inch and stagger one meter 36 inch minimum. Place the full width of each ply in hot bitumen immediately behind the bitumen applicator. Lay plies free of wrinkles, creases, ridges, or fishmouths. Extend felts approximately 50 mm

SECTION 07 51 13 Page 17

2 inch above top of cant strips at vertical surfaces and to top of cant strips elsewhere. Trim felts to a neat fit around vent pipes, roof drains, and other projections. Avoid traffic on mopped surfaces when the bitumen is fluid and for a minimum of one hour after ply application.

3.3.4.1 Hot-Mopping of Ply Felts

Bond plies to each other and to the [base sheets] [substrate] with hot asphalt. Apply felts immediately following application of asphalt. Do not work ahead with asphalt. At the instant felts come into contact with asphalt, asphalt must be completely fluid, with asphalt temperatures within specified EVT range. Apply asphalt uniformly in a full, continuous mopping and firmly bonding film. Apply asphalt at the rate of approximately 13 kg per 10 sq. meters 25 pounds per 100 sq. feet plus or minus 25 percent.

Require application rate on the high end of the application range when mopping directly to absorptive insulation substrates of perlite and woodfiber. As felts are rolled into the hot asphalt, immediately squeegee, roll or broom down to eliminate trapped air and to provide tight, smooth laminations without wrinkles, buckles, kinks, or fish mouths. Bitumen must be visible beyond all edges of each ply as it is being installed. Install individual ply and the completed roof membrane system free of air pockets, felt delaminations, ridges, creases, fishmouths, dry laps, or blisters. Do not lay felts dry or turn back laps for mopping between plies.

3.3.4.2 Backnailing of Ply Felts

Unless otherwise recommended by the roof membrane manufacturer and approved by the Contracting Officer, [provide minimum 90 mm 3-1/2 inch wide nailing strips matching insulation thickness and applied perpendicular to roof slope for backnailing of roof membrane. Space nailing strips as recommended by the membrane manufacturer, but not exceeding 5 meters 16 feet on center unless approved otherwise by the Contracting Officer. Coordinate the nailer installation with insulation requirements. As the felt plies are installed, nail each ply 25 mm 1 inch from the leading edge at each nailer line.] [fasten each felt ply 25 mm 1 inch from the leading edge and spaced at maximum 5 m 15 feet on center along the leading edge.] Provide fasteners with a 25 mm 1 inch diameter metal cap or fasten through 25 mm 1 inch diameter caps. Set fasteners firm and flush without puncturing felt ply. Conceal fasteners with succeeding plies of felt.

3.3.4.3 Valleys and Ridges

Valleys: Apply roofing at valleys and waterways in the following manner:

Continue base sheets across valleys and terminate 450 millimeter 18 inch from the valley.

Continue felt plies across valleys and terminate 300 millimeter 12 inch from the valley. Terminate exposed laps on a line 300 millimeter 12 inch from, and parallel to, the gutter valley. Provide two plies of felt, 225 and 300 millimeter 9 and 12 inch wide, successively mop in over each felt line of the termination.

If the application can be completed without wrinkles, buckles, or fishmouths and if side laps do not face the direction of drainage, roofing felts and base sheets may be laid continuously across or parallel to shallow valleys such as those formed by reverse-slope roofs. For this application, reinforce valleys with one ply of felt, 900 millimeter 36 inch wide, center on the valley gutter and lay in a solid mopping of asphalt over the top ply of roofing.

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3.3.5 Membrane Flashing

Provide two plies of modified bitumen membrane strip flashing and sheet flashing in the angles formed where the roof deck abuts walls, curbs, ventilators, pipes, and other vertical surfaces, and where necessary to make the work watertight. Top ply of flashing must be granule-surfaced modified bitumen membrane. Install flashing after plies of roof membrane felt have been applied but before aggregate surfacing is applied. Cut at a 45 degree angle across terminating end lap area of cap membrane prior to applying adjacent overlapping cap membrane. Press flashing into place to ensure full adhesion and avoid bridging. Ensure full lap seal in all lap areas. Mechanically fasten top edge of base flashing 150 mm 6 inch on center through minimum 25 mm 1 inch diameter tin caps with fasteners of sufficient length to embed minimum 25 mm 1 inch into attachment substrate.[ Apply matching granules in any areas of asphalt bleed out while the asphalt is still hot.] Apply membrane liner over top of exposed nailers and blocking and to overlap top edge of base flashing installation at curbs, parapet walls, expansion joints and as otherwise indicated to serve as waterproof lining under sheet metal flashing components.

3.3.5.1 Strip Flashing

Set primed flanges of sheet metal flashings to be incorporated into roofing system in a uniform coating of asphalt roof cement not less than 1/16 inch thick applied over the ply felts. Strip-in with one layer of smooth surface modified bitumen membrane and cap with granule-surfaced modified bitumen membrane. Set strip flashing in hot asphalt or cement to the tops of the flanges, roofing membrane, and to each other. Use coatings of asphalt roof cement not less than 1/16 inch thick for ply felt. Use hot asphalt or modified bitumen cement for modified bitumen sheets. Extend first stripping ply not less than 100 mm 4 inch beyond outer edge of flange onto roof membrane. Extend each additional ply 100 mm 4 inch beyond the edge of the previous ply.

3.3.5.2 Membrane Flashing at Roof Drain

Extend roofing plies to edge of drain bowl opening at roof drain deck flange. Neatly fit and press primed roof drain flashing into heavy coat of asphalt roof cement applied to top of roofing plies. Strip in and completely cover flashing with two layers of modified bitumen sheet, extending the first sheet 150 mm 6 inch on the roofing beyond the edge of flashing. Extend the cap sheet 150 mm 6 inch beyond the previous flashing ply. Bond the two layers to the metal flashing and to each other with hot asphalt. Securely clamp membrane, metal flashing, and strip flashing in the flashing clamping ring. Secure clamps so that strip flashing and metal flashing are free from wrinkles and folds. Trim membrane, flashing, and stripping flush with inside of clamping ring.

3.3.5.3 Pre-fabricated Curbs

Anchor prefabricated curbs securely to nailer or other base substrate as indicated and flash with modified bitumen flashing membrane.

3.3.5.4 Set-On Accessories

Where pipe or conduit blocking, supports and similar roof accessories are set on the membrane, adhere walkpad material to bottom of accessories prior to setting on roofing membrane. Install set-on accessories to permit normal movement due to expansion, contraction, vibration, and similar

SECTION 07 51 13 Page 19 occurrences without damaging roofing membrane. Do not mechanically secure set-on accessories through roofing membrane into roof deck substrate.

3.3.5.5 Lightning Protection

Flash or attach lightning protection system components to the roof membrane in a manner acceptable to the roof membrane manufacturer.

3.3.6 Roof Walkpads

Install walkpads at roof access points and where otherwise indicated for traffic areas and for access to mechanical equipment, in accordance with the modified bitumen sheet roofing manufacturer's printed instructions.

Provide minimum 150 mm 6 inch separation between adjacent walkpads to accommodate drainage. Provide walkpad or an additional layer of cap sheet under precast concrete paver blocks to protect the roofing.

3.3.7 Elevated Metal [Walkways] [and] [Platforms]

Provide protection mat of walkpad material, or other material approved by the Contracting Officer, at all surface bearing support locations.

3.3.9 Aggregate Surfacing

After completion of roof membrane ply and flashing installation, and correction of tears, gouges or other deficiencies in the installed work, apply aggregate surfacing. Uniformly flood coat the surface with hot asphalt at a rate of approximate 2.9 kg 60 pounds per square. While asphalt is still hot, apply gravel aggregate surfacing material at a rate of

19.5 kg 400 pounds per square. Provide for full and uniform coverage of the roof surface. Approximately 50 percent of the aggregate must be solidly adhered in the asphalt.

3.3.11 Correction of Deficiencies

Where any form of deficiency is found, take additional measures to determine the extent of the deficiency and perform corrective actions as directed by the Contracting Officer.[ Where interply moppings are too light, apply additional two plies of felt in full moppings of asphalt.

Apply with 100 mm4 inch side and end laps. Where free water, skips, excessive voids, dry laps, desponding or any form of delamination are discovered between the plies, remove and rebuild affected area. Correction of inadequate number of plies, improper lap widths, or non-uniform or excessive asphalt mopping must be as directed by the Contracting Officer.]

Where insulation is found to be wet, remove insulation and provide new built-up roofing and insulation.

3.3.12 Clean Up

Remove debris, scraps, containers and other rubbish and trash resulting from installation of the roofing system from job site each day.

3.4 PROTECTION OF APPLIED ROOFING

3.4.1 Protection Against Moisture Absorption

When precipitation is imminent and at the end of each day's work, protect applied roofing as follows:

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3.4.2 Water Cutoffs

Straighten insulation line using loose-laid cut insulation sheets and seal the terminated edge of modified bitumen roofing system in an effective manner.[ Seal off flutes in metal decking along the cutoff edge.] Remove the water cutoffs to expose the insulation when resuming work, and remove the insulation sheets used for fill-in.

3.4.3 Temporary Flashing for Permanent Roofing

Provide temporary flashing at drains, curbs, walls and other penetrations and terminations of roofing sheets until permanent flashings can be applied. Remove temporary flashing before applying permanent flashing.

3.4.4 Temporary Walkways, Runways, and Platforms

Do not permit storing, walking, wheeling, and trucking directly on applied roofing materials. Provide temporary walkways, runways, and platforms of smooth clean boards, mats or planks as necessary to avoid damage to applied roofing materials, and to distribute weight to conform to live load limits of roof construction. Use rubber-tired equipment for roofing work.

3.4.5 Glaze Coat

Use light glaze coating of bitumen to waterproof roof areas requiring extended time to complete. Glaze coating must be at the discretion of the

Contracting Officer. Apply bitumen glaze coat on exposed felts at a rate of

0.25 kg to 0.50 kg per square meter 5 to 10 pounds per square. Lower application rates, in accordance with membrane manufacturer's recommendations, may be required when modified bitumen cap sheet surfacing is specified. Provide valleys and low areas that may pond water with glaze coating.

3.5 FIELD QUALITY CONTROL

Perform field tests in the presence of the Contracting Officer. Notify the

Contracting Officer one day before performing tests.

3.5.1 Test for Surface Dryness

Before application of insulation or membrane materials and starting work on the area to be roofed, perform test for surface dryness in accordance with the following:

a. Foaming: When poured on the surface to which materials are to be applied, one pint of asphalt when heated in the range of 176 to 204 degrees C 350 to 400 degrees F, must not foam upon contact.

b. Strippability: After asphalt used in the foaming test application has cooled to ambient temperatures, test coating for adherence. Should a portion of the sample be readily stripped clean from the surface, do not consider the surface to be dry and do not start application.

Should rain occur during application, stop work and do not resume until surface has been tested by the method above and found dry.

c. Prior to installing any roof system on a concrete deck, conduct a test per ASTM D4263. The deck is acceptable for roof system application when there is no visible moisture on underside of plastic sheet after

24 hours.

3.5.2 Construction Monitoring

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During progress of the roof work, perform visual inspections to ensure compliance with specified parameters. Additionally, verify the following:

a. Equipment is in working order. Metering devices are accurate.

b. Materials are not installed in adverse weather conditions.

c. Substrates are in acceptable condition, in compliance with specification, prior to application of subsequent materials.

Nailers and blocking are provided where and as needed.

Insulation substrate is smooth, properly secured to its substrate, and without excessive gaps prior to membrane application.

The proper number, type, and spacing of fasteners are installed.

Materials comply with the specified requirements.

All materials are properly stored, handled and protected from moisture or other damages.

Asphalt is heated and applied within the specified temperature parameters.

Hot asphalt application is provided uniformly for voidless coverage and as necessary to ensure full adhesion of materials.

Materials are set in place while asphalt is within the specified temperature range.

The proper number and types of plies are installed, with the specified overlaps.

Applied membrane surface is inspected, cleaned, dry, and repaired as necessary prior to cap sheet installation.

Membrane is without ridges, wrinkles, kinks, fishmouths, or other voids or delaminations.

Installer adheres to specified and detailed application parameters.

Associated flashings and sheet metal are installed in a timely manner in accord with the specified requirements.

Temporary protection measures are in place at the end of each work shift.

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