07 51 13 13 Built-Up Asphalt Roofing Cold Applied.docx

VA Medical Center – Albany, NY Samuel S. Stratton Facility Replacement of Chiller Plant Roof Issued 2/15/2022

SECTION 07 51 13.13 - BUILT-UP ASPHALT ROOFING, COLD-APPLIED

This Tremco PRODUCT MASTERSPEC specifies Tremco BURmastic 100 and BURmastic 200 cold-applied built-up asphalt roof membrane systems, including hybrid systems with MB cap sheets, consisting of multiple plies of roofing felts set in cold asphalt adhesive, with roofing accessories including substrate board, vapor retarder, insulation, cover board, fasteners, membrane flashings, and granular, aggregate or smooth-coating surfaces.

The companion Sections 076200 "Sheet Metal Flashing and Trim", 077100 "Roofing Specialties", and 077129 "Manufactured Roof Expansion Joints" specify the low-slope metal flashings and custom or manufactured roof edge, copings and roof drainage items that together with the work of this section form the total roof system. Warranty requirements for this Section cross-reference these sections.

Roofing Installer's Warranty Form is now Section 070101.01 MEMBRANE ROOFING INSTALLER'S WARRANTY. Be sure to include this document in your project when required.

GENERAL

SUMMARY

Section Includes:

A Hybrid BUR system utilizes SBS MB plies in the roof membrane such as BURmastic Composite Ply and POWERply sheets.

Adjust list below to correspond to roof system products selected in Part 2 and assembly described in Part 3.

Cold-applied, built-up asphalt roofing system on concrete deck, including but not limited to:

Vapor retarder.

Roof insulation.

Roof insulation cover board.

Roofing membrane ply sheets.

Base flashings.

Roof surfacing consisting of surfacer with aggregate surfacing.

Edit "Related Sections" Paragraph below as required to coordinate work specified in several sections. Only list sections that are actually included in the Project Manual and available to the Con-tractor.

Related Sections:

Division 07 Section "Preparation for Re-Roofing" for existing roofing tear-off, patching, and substrate preparation for reroofing.

Division 07 Section "Roof Specialties" for manufactured copings and roof edge flashings.

DEFINITIONS

Roofing Terminology: Refer to ASTM D1079 "Standard Terminology Relating to Roofing and Waterproofing" and glossary in applicable edition of NRCA's "The NRCA Roofing Manual: Membrane Roof Systems" for definition of terms related to roofing work in this Section.

PREINSTALLATION MEETINGS

Retain paragraph below if Work of this Section is extensive or complex enough to justify a preinstallation conference. Preinstallation roofing conference is recommended with or without a preliminary roofing conference.

Preinstallation Roofing Conference: Conduct conference at Project site.

Meet with Owner, Owner's Consultant Owner's insurer if applicable, testing and inspecting agency representative, roofing Installer, roofing manufacturer's representative, and installers whose work interfaces with or affects roofing, including installers of roof accessories and roof-mounted equipment.

Review drawings and specifications.

Review methods and procedures related to roofing installation, including manufacturer's written instructions.

Review and finalize construction schedule and verify availability of materials, Installer's personnel, equipment, and facilities needed to make progress and avoid delays.

Examine substrate conditions and finishes for compliance with requirements, including flatness and fastening.

Review structural loading limitations of roof deck during and after roofing.

Review base flashings, special roofing details, roof drainage, roof penetrations, equipment curbs, and condition of other construction that will affect roofing.

Review governing regulations and requirements for insurance and certificates if applicable.

Review temporary protection requirements for roofing during and after installation.

Review roof observation and repair procedures after roofing installation.

ACTION SUBMITTALS

Product Data: For each type of product indicated.

Verify that the specified roof assembly has been tested for wind uplift resistance, and meets or exceeds the uplift pressures specified under the Performance Requirements article.

Wind Uplift Resistance Submittal: For roofing system, indicating compliance with wind uplift performance requirements.

INFORMATIONAL SUBMITTALS

Qualification Data: For Installer, Manufacturer, and Roofing Inspector.

Include letter from Manufacturer written for this Project indicating approval of Installer.

Retain first paragraph below if retaining "Roofing System Design," "FM Approvals Listing," or any "Energy Performance" paragraph in "Performance Requirements" Article.

Manufacturer Certificates: Signed by roofing manufacturer certifying that built-up roofing complies with requirements specified in "Performance Requirements" Article.

Submit evidence of compliance of proposed roofing system with performance requirements, including UL listing certificate.

Product Compatibility: Indicate manufacturer has verified compatibility of roofing system components, including but not limited to: Roofing membrane, flashing sheets, adhesives, and sealants.

Warranties: Unexecuted sample copies of special warranties.

Field Quality Control Reports: Reports of Roofing Inspector. Include weather conditions, description of work performed, tests performed, defective work observed, and Contractor's corrective actions taken to correct defective work.

Submit reports within 48 hours after inspection.

CLOSEOUT SUBMITTALS

Maintenance Data: To include in maintenance manuals.

Warranties: Executed copies of warranties.

QUALITY ASSURANCE

Installer Qualifications: An employer of workers trained and certified by manufacturer, including a full-time on-site supervisor with a minimum of five years' experience installing similar work, able to communicate verbally with Contractor, Owner's Consultant, and employees, and qualified by the manufacturer to furnish warranty of type specified.

Manufacturer Qualifications: Approved manufacturer with UL listed roofing systems comparable to those specified for this Project, with minimum five years' experience in manufacture of comparable products in successful use in similar applications, and able to furnish warranty with provisions matching specified requirements.

Roofing Inspector Qualifications: A technical representative of manufacturer, not engaged in the sale of products, and experienced in the installation and maintenance of the specified roofing system, qualified to perform roofing observation and inspection specified in Field Quality Control Article to determine Installer's compliance with the requirements of this Project, and approved by the manufacturer to issue warranty certification. The Roofing Inspector shall be one of the following:

An authorized full-time technical employee of the manufacturer.

An independent party certified as a Registered Roof Observer by the International Institute of Building Enclosure Consultants (formerly the Roof Consultants Institute) retained by the Contractor or the Manufacturer and approved by the Manufacturer.

Manufacturer's Installation Instructions: Obtain and maintain on-site manufacturer's written recommendations and instructions for installation of products.

DELIVERY, STORAGE, AND HANDLING

Deliver roofing materials to Project site in original containers with seals unbroken and labeled with manufacturer's name, product brand name and type, date of manufacture, approval or listing agency markings, and directions for storing and mixing with other components.

Store liquid materials in their original undamaged containers in a clean, dry, protected location and within the temperature range required by roofing manufacturer. Protect stored liquid material from direct sunlight.

Discard and legally dispose of liquid material that cannot be applied within its stated shelf life.

Protect roof insulation materials from physical damage and from deterioration by sunlight, moisture, soiling, and other sources. Store in a dry location. Comply with insulation manufacturer's written instructions for handling, storing, and protecting during installation.

Handle and store roofing materials and place equipment in a manner to avoid permanent deflection of deck.

PROJECT / FIELD CONDITIONS

Retain, revise, or delete paragraphs and subparagraphs in this article to suit Project.

Weather Limitations: Proceed with installation only when existing and forecasted weather conditions permit roofing to be installed according to manufacturer's written instructions and warranty requirements.

Daily Protection: Coordinate installation of roofing so insulation and other components of roofing system not permanently exposed are not subjected to precipitation or left uncovered at the end of the workday or when rain is forecast.

Provide tie-offs at end of each day's work to cover exposed roofing and insulation with a course of roofing sheet securely in place with joints and edges sealed.

Complete terminations and base flashings and provide temporary seals to prevent water from entering completed sections of roofing.

Remove temporary plugs from roof drains at end of each day.

Remove and discard temporary seals before beginning work on adjoining roofing.

WARRANTY

Manufacturer's Warranty: Roof System Manufacturer's standard form in which Manufacturer agrees to repair or replace components of roofing system that fail in materials or workmanship within warranty period, as follows.

Form of Warranty: Manufacturer's standard warranty form.

Scope of Warranty: Work of this Section and including sheet metal details and termination details installed by the roof system Installer and approved by the Roof System Manufacturer.

Warranty Period: 25 years from date of completion.

Manufacturer Inspection Services: By manufacturer's technical representative, to report maintenance responsibilities to Owner necessary for preservation of Owner's warranty rights. The cost of manufacturer's inspections is included in the Contract Sum.

Inspections to occur in following years: 2, 5, 10, 15, 20 following completion.

Installer Warranty: Installer's warranty signed by Installer, as follows.

Form of Warranty: Form acceptable to Roofing Manufacturer and Owner.

Scope of Warranty: Work of this Section.

Warranty Period: 2 years from date of completion.

PRODUCTS

MANUFACTURERS

Basis of Design: The roof system specified in this Section is based upon products of Tremco, Inc., Beachwood, OH, (800) 562-2728, www.tremcoroofing.com that are named in other Part 2 articles. Provide specified products or comparable products of one of the following.

Ecology.

<Insert manufacturer name>.

*Specifier: You may include the following in addition to or in lieu of listing other approved manufacturers or as a stand-alone "approved equal" provision.

Manufacturers of comparable products: Approved by Architect prior to bid.

Retain "Source Limitations" Paragraph below if required to comply with FM Global, UL, applicable building code, or to comply with provisions of manufacturer's warranty.

Source Limitations: Obtain components for roofing system from same manufacturer as membrane roofing or manufacturer approved by membrane roofing manufacturer.

PERFORMANCE REQUIREMENTS

General Performance: Roofing shall withstand exposure to weather without failure or leaks due to defective manufacture or installation.

Accelerated Weathering: Roofing system shall withstand 2000 hours of exposure when tested according to ASTM G152, ASTM G154, or ASTM G155.

Retain first paragraph below if roofing system is to be designed to withstand uplift pressure established by IBC 1504.3 that is applied in most US jurisdictions. Coordinate this information with Design Professional. Refer to, rather than duplicate, wind uplift requirements indicated elsewhere in the contract documents.

Roofing System Design: Provide roofing system that is identical to systems that have been successfully tested by a qualified testing and inspecting agency in accordance with ANSI/FM 4474, UL 580, or UL 1897, and to resist uplift pressures calculated in accordance with ASCE-7 and applicable code.

If including pressures in the specification, it is recommended that you insert pressures calculated per code and then apply a 2X safety factor, as follows: Applicable version of ASCE 7 Strength Design Method x 0.6 = Allowable Stress Design X Safety Factor of 2 = Minimum Recommended Pressure for each Zone. Insert the Minimum Recommended Pressure value into the spec for each zone (values may be rounded up). Where Zone 1 and Zone 1' (prime) are indicated, list the higher pressure or manually insert another subparagraph.

Insert pressure value and then select either IP or SI unit of measure. If both IP and SI are required, use in-line editing to revise.

Zone 1 (Field-of-Roof) Uplift Pressure: 31 psf.

Zone 2 (Perimeter) Uplift Pressure: 52 psf, located within 6.5 ft. of roof perimeter.

Zone 3 (Corners) Uplift Pressure: 78 psf, located within 6.5 ft. of outside corners.

Flashings and Fastening: Provide base flashings, perimeter flashings, detail flashings and component materials and installation techniques that comply with requirements and recommendations of the following:

NRCA Roofing Manual (Sixth Edition) for construction details and recommendations.

SMACNA Architectural Sheet Metal Manual (Seventh Edition) for construction details.

Retain the following as applicable; referenced section(s) must be included in the Project Manual.

Comply with requirements of Division 07 Section "Roof Specialties".

Retain one of three options in first paragraph below based on fire classification of roof assembly and roof covering. Delete paragraph if including exterior fire-test exposure in FM Approvals class designation in "Performance Requirements" Article. Class A rating meets (IBC) building code requirements for all construction types; Refer to applicable code for acceptability of Class B or C ratings based upon construction type. Specify a Class A tested assembly whenever possible.

Exterior Fire-Test Exposure: ASTM E 108, Class A; for application and roof slopes indicated, as determined by testing identical membrane roofing materials by a qualified testing agency. Materials shall be identified with appropriate markings of applicable testing agency.

MATERIALS, GENERAL

Material Compatibility: Roofing materials shall be compatible with one another and adjacent materials under conditions of service and application required, as demonstrated by roof membrane manufacturer based on testing and field experience.

Retain "FM Global Material Standards" Paragraph below if FM material standards apply, but pro-posed system is not an FM RoofNav-listed system. Each product specified must be listed in RoofNav for its proposed use in the roof assembly.

FM Global Material Standards: Roofing, base flashings, and component materials shall be identical to materials that comply with requirements in FM Global 4470 as part of a roofing system listed or approved by FM Global. Identify applicable materials with FM Global markings.

ROOFING MEMBRANE MATERIALS

Ply Sheets:

SBS-modified asphalt coated composite polyester / fiberglass/fiberglass mat reinforced high tensile strength base sheet, ASTM D4601 Type II.

Basis of design product: Tremco, BURmastic Composite Ply HT.

Tensile Strength at 77 deg. F (25 deg. C), minimum, ASTM D5147: Machine direction, 165 lbf/in (725 N); Cross machine direction, 150 lbf/in (660 N).

Tear Strength at 77 deg. F (25 deg. C), minimum, ASTM D5147: Machine direction, 260 lbf (1150 N); Cross machine direction, 230 lbf ( 1120 N).

Thickness, minimum, ASTM D5147: 0.060 inch (1.5 mm).

Membrane Flashing Sheets:

Flashing Sheet, Thermoset: Elastomeric polyester reinforced sheet with EPDM and SBR elastomers.

Basis of design product: Tremco, TRA Elastomeric Sheeting.

Breaking Strength, minimum, ASTM D751: Machine direction 350 lbf (1550 N); Cross machine direction 300 lbf (1330 N).

Tear Strength, minimum, ASTM D751: Machine direction 77 lbf (342 N); Cross machine direction 77 lbf (342 N).

Elongation at Failure, minimum, ASTM D751: Machine direction 30 percent; Cross-machine direction 35 percent.

Low Temperature Flexibility, minimum, ASTM D2136: -40 deg. F (-40 deg. C).

Thickness, minimum, ASTM D751: 0.045 inch (1.1 mm).

Color: Black.

Detailing Fabric:

Woven Glass Fiber Mesh, Vinyl-Coated: Non-shrinking, non-rotting, vinyl-coated woven glass mesh for reinforcing flashing seams, membrane laps, and other roof system detailing.

Basis of design product: Tremco, BURmesh.

Tensile strength, 70 deg. F, min ASTM D146: Warp, 65 lbf/in (285 N); fill, 75 lbf/in (310 N).

Color: Aqua green.

COLD-APPLIED ADHESIVE MATERIALS

General: Adhesive and sealant materials recommended by roofing manufacturer for intended use and compatible with built-up roofing.

Liquid-type auxiliary materials shall comply with VOC limits of authorities having jurisdiction.

Delete subparagraph below unless low-emitting materials are required for sustainable design compliance. Verify that selected products comply with requirements. Local jurisdictions might have more stringent VOC limits.

Adhesives and sealants shall comply with the following limits for VOC content:

Plastic Foam Adhesives: 50 g/L.

Nonmembrane Roof Sealants: 300 g/L.

Sealant Primers for Nonporous Substrates: 250 g/L.

Sealant Primers for Porous Substrates: 775 g/L.

Delete Subparagraph below applies unless required for sustainable design compliance. This requirement applies to all products inside the weather barrier which is the cap sheet or top ply. Verify that selected products comply with requirements.

Adhesives and sealants shall comply with the testing and product requirements of the California Department of Public Health's "Standard Method for the Testing and Evaluation of Volatile Organic Chemical Emissions from Indoor Sources Using Environmental Chambers."

Asphalt Primer:

Asphalt primer, water-based, polymer modified.

Basis of design product: Tremco, TREMprime WB.

Volatile Organic Compounds (VOC), maximum, ASTM D3960: 2 g/L.

Color: Brown/black.

Ply Sheet Adhesive:

Cold-applied roofing adhesive and surfacer, one-part, formulated for compatibility and use with specified roofing membranes and flashings.

Basis of design product: Tremco, BURmastic Adhesive.

Volatile Organic Compounds (VOC), maximum, ASTM D6511: 250 g/L.

Nonvolatile Content, minimum, ASTM D6511: 72 percent.

Flashing Sheet Adhesive:

Bonding and Flashing Adhesive, SEBS/SIS modified asphalt, for elastomeric flashing membranes.

Basis of design product: Tremco, Sheeting Bond.

VOC, maximum, ASTM D3960: 250 g/L.

Adhesion in peel, minimum, ASTM D1876: 3 lbf/in (0.5 N/mm).

Lap shear adhesion, minimum, ASTM D816: 18 psi (124 kPa).

Color: Black.

AUXILIARY BUILT-UP ROOFING MATERIALS

General: Auxiliary materials recommended by roofing system manufacturer for intended use and compatible with roofing membrane.

Stripping Reinforcing Fabric:

Woven Glass Fiber Mesh, Vinyl-Coated: Non-shrinking, non-rotting, vinyl-coated woven glass mesh for reinforcing flashing seams, membrane laps, and other roof system detailing.

Basis of design product: Tremco, BURmesh.

Tensile strength, 70 deg. F, min ASTM D146: Warp, 65 lbf/in (285 N); fill, 75 lbf/in (310 N).

Color: Aqua green.

Retain "Elastomeric Mastic" Paragraph below if mastic is needed for moving joints in sheet metal accessories or for certain locations where asphalt roofing cement may be inadequate or undesirable.

Elastomeric Mastic:

Roofing Mastic, Low-Volatile: Modified asphalt elastomeric roof mastic, one-part, trowel-grade, formulated for compatibility and use with specified roofing membranes and flashings.

Basis of design product: Tremco, POLYroof LV.

Volatile Organic Compounds (VOC), maximum, ASTM D3960: 300 g/L.

Elongation at -30 deg. F (-34 deg. C), minimum, ASTM D412: 100 percent.

Tensile strength at 77 deg F (25 deg C), ASTM D412: 30 psi (207 kPa).

Flexibility at -40 deg. F (-40 deg. C), ASTM D3111: No cracking.

Nonvolatile matter, ASTM D4586 : 70 percent.

Miscellaneous Accessories: Provide miscellaneous accessories recommended by built-up roofing manufacturer.

VAPOR RETARDER

Vapor Retarder Membrane:

SBS/SIS/SEBS-modified asphalt-coated glass-fiber reinforced sheet, smooth surfaced, designed for heat-welded applications, ASTM D6163 Type I Grade S.

Basis of design product: Tremco, POWERply Standard Smooth HW (Heat Weld).

Tensile Strength at 77 deg. F (25 deg. C), minimum, ASTM D5147: 70 lbf/in (12 kN/m) machine direction; 50 lbf/in (8 kN/m) cross-machine direction.

Tear Strength at 77 deg. F (25 deg. C), minimum, ASTM D5147: 100 lbf (445 N) machine direction; 80 lbf (400 N) machine direction.

Elongation at 77 deg. F (25 deg. C), minimum, ASTM D5147: 4 percent machine direction; 4 percent cross-machine direction.

Low Temperature Flex, ASTM D5147: -30 deg. F (-23 deg. C).

Thickness, ASTM D5147: 0.118 inch (3.0 mm).

Vapor Retarder Primer:

Asphalt primer, water-based, polymer modified.

Basis of design product: Tremco, TREMprime WB.

Volatile Organic Compounds (VOC), maximum, ASTM D3960: 2 g/L.

Color: Brown/black.

ROOF INSULATION MATERIALS

Roofing Insulation, General: Preformed roof insulation boards manufactured or approved by roofing manufacturer, selected from manufacturer's standard sizes suitable for application, of thicknesses indicated Retain the following for tapered systems which are comprised of flat-stock base layer(s) and tapered stock upper layer. New roofs require a slope of not less than 1/4 inch/ft (1:48). Replacement roofs should be installed at 1/4 inch/ft (1:48) when possible however a lesser slope of 1/8 inch/ft (1:96) may acceptable; confirm applicable code requirement. Saddles, crickets, edge strips, etc. must be twice the slope of the roof and are listed under the general requirement, above.

Tapered Insulation: Provide factory-tapered insulation boards fabricated to slope of 1/8 inch per 12 inches (1:96) unless otherwise indicated.

Retain the following for all roof assemblies using flat or tapered insulation and requiring saddles, crickets, edge strips, drain sumps or any other miscellaneous tapered components.

Provide preformed saddles, crickets, tapered edge strips, and other insulation shapes where indicated for sloping to drain. Fabricate to slopes indicated, not less than two times the roof slope.

Roof Insulation:

Board Insulation, Polyisocyanurate: CFC- and HCFC- free, with recycled content glass-fiber mat facer on both major surfaces, ASTM C1289 Type II Class 1.

Basis of design product: Tremco, Trisotech Insulation.

Compressive Strength, ASTM D1621: Grade 2: 20 psi (138 kPa).

Conditioned Thermal Resistance at 75 deg. F (24 deg. C): 14.4 at 2.5 inches (50.8 mm) thick.

ROOF INSULATION ACCESSORIES

Insulation Cover Board:

Gypsum panel, glass-mat-faced, primed, ASTM C1177/C1177M.

Basis of design product: Tremco/GP Gypsum DensDeck Prime.

Thickness: 1/2 inch (12 mm).

Insulation Adhesive:

Urethane adhesive, bead-applied, low-rise two-component solvent-free low odor, formulated to adhere roof insulation to substrate.

Basis of design product: Tremco, Low Rise Foam Insulation Adhesive.

Flame Spread Index, ASTM E84: 10.

Smoke Developed Index, ASTM E84: 30.

Volatile Organic Compounds (VOC), maximum, ASTM D3960: 0 g/L.

Tensile Strength, minimum, ASTM D412: 250 psi (1720 kPa).

Peel Adhesion, minimum, ASTM D903: 17 lbf/in (2.50 kN/m).

Flexibility, 70 deg. F (39 deg. C), ASTM D816: Pass.

Wood Cant Strips: Comply with requirements in Division 06 rough carpentry Section.

Tapered Edge Strips: ASTM C208, Type II, Grade 1, cellulosic-fiber insulation board.

SURFACING

IMPORTANT NOTE: The use of aggregate on roofs as surfacing or ballast is restricted by code in most jurisdictions. Review applicable code to determine whether ballast/aggregate is permitted. For projects governed by IBC, refer to Chapter 15 (Section & Table 1504.8 in IBC-2015 and IBC 2018).

Cold-Applied Adhesive Surfacer:

Cold-applied roofing adhesive and surfacer, one-part, formulated for compatibility and use with specified roofing membranes and flashings.

Basis of design product: Tremco, BURmastic Adhesive.

Volatile Organic Compounds (VOC), maximum, ASTM D6511: 250 g/L.

Nonvolatile Content, minimum, ASTM D6511: 72 percent.

Aggregate Surfacing Material:

Aggregate Stone Surfacing: Clean, dry, opaque, water-worn or crushed stone, free of sharp edges.

Basis of design product: Aggregate Stone Surfacing.

Size, ASTM D 1863: No. 6 or 67.

Aggregate application rate, average: 400 lb/100 sq ft (19.5 k/m2).

EXECUTION

EXAMINATION

Examine substrates, areas, and conditions, with Installer present, for compliance with the following requirements and other conditions affecting performance of roofing system:

Retain those paragraphs below that pertain to the deck and substrate conditions of the project.

Verify that roof openings and penetrations are in place and curbs are set and braced and that roof drain bodies are securely clamped in place.

Retain paragraph below if project will be let with wood cants, blocking, and nailers installed under another trade subcontract.

Verify that, blocking, curbs, and nailers are securely anchored to roof deck at penetrations and terminations and that nailers match thicknesses of insulation. wood cants Concrete Roof Deck:

Verify that minimum concrete drying period recommended by roofing manufacturer has passed.

Select one of the following two subparagraphs (plastic sheet or moisture probe) for applicable moisture test method.

Verify that concrete substrate is visibly dry and free of moisture. Test for capillary moisture by plastic sheet method according to ASTM D4623.

Verify that existing substrate is sound and dry.

Proceed with installation only after unsatisfactory conditions have been corrected.

PREPARATION

Clean substrate of dust, debris, moisture, and other substances detrimental to roofing installation according to roofing manufacturer's written instructions. Remove sharp projections.

Prevent materials from entering and clogging roof drains and conductors and from spilling or migrating onto surfaces of other construction. Remove roof-drain plugs when no work is taking place or when rain is forecast.

Include and edit concrete deck priming when applicable for vapor retarder. Coordinate with Insulation Installation Article for priming concrete deck in preparation for adhered insulation or adhering membrane directly to deck. Refer to product data for priming requirements.

Concrete Surface Priming: Prime surface of concrete deck with asphalt primer at rate required by manufacturer and allow primer to dry.

INSTALLATION, GENERAL

Install roofing system in accordance with manufacturer’s written instructions, approved shop drawings, and Contract Documents.

Retain paragraph below if project will be let with wood cants, blocking, and nailers installed under the work of the roofing Installer.

Install wood cants, blocking, curbs, and nailers in accordance with requirements of Division 06 Section "Miscellaneous Rough Carpentry."

ROOFING INSTALLATION DETAILS

Choose only one of the following two NRCA Installation Details paragraphs. The first is a short version of the second.

Retain first "NRCA Installation Details" Paragraph below and delete following Paragraph and selected subparagraphs if Project drawings include adequate roofing installation details.

NRCA Installation Details: Install roofing system in accordance with applicable NRCA Manual Plates and NRCA recommendations; modify as required to comply with manufacturer's approved details.

VAPOR RETARDER INSTALLATION

Delete this Article if not required. Retain selected vapor retarder material from paragraphs below. Vapor retarder must be fully supported by substrate; steel deck requires substrate board. Retitle article "Air Barrier Installation" if that is primary function; revise installation requirements if necessary. Verify VOC content allowed for liquid-applied products applied inside weather envelope of sustainable design and LEED projects.

Vapor Retarder Installation, General: Completely seal vapor retarder/air barrier at terminations, obstructions, and penetrations to prevent air movement into roofing system. Seal vapor retarder/air barrier to air barrier in adjacent construction at perimeter of roofing system.

Torch-Applied SBS Modified Sheet Vapor Retarder: Install one lapped vapor retarder course and torch-apply to substrate, according to roofing system manufacturer's written instructions.

INSULATION INSTALLATION

Comply with built-up roofing manufacturer's written instructions for installing roof insulation.

Coordinate installing membrane roofing system components so insulation is not exposed to precipitation or left exposed at the end of the workday.

Cant Strips: Install and secure preformed 45-degree cant strips at junctures of built-up roofing with vertical surfaces or angle changes greater than 45 degrees.

Tapered Insulation and Crickets: Install tapered insulation under area of roofing to conform to slopes indicated.

Where crickets are indicated or required to provide positive slope to drain, make slope of crickets minimum of two times the roof slope and not less than 1/4 inch in 12 inches((1:48)).

Install insulation with long joints of insulation in a continuous straight line with end joints staggered between rows, abutting edges and ends between boards. Fill gaps exceeding 1/4 inch (6 mm) with insulation.

Cut and fit insulation within 1/4 inch (6 mm) of nailers, projections, and penetrations.

Insulation manufacturers usually recommend thickness in first paragraph below as maximum thickness of single insulation layer. Edit paragraphs below to establish minimum and average minimum overall thickness of insulation. Coordinate with drawings. Use actual thickness in lieu of R-value/RSI to avoid disputes based upon alternate methods of calculating thermal resistance of insulation.

R-Value is an imperial system unit of measurement (ft2·°F·h/BTU) and the RSI Value is a metric system unit of measurement (sq. m.·K/W). To convert an R-Value to an RSI Value, divide the R-Value by 5.678. Conversely, to convert an RSI Value to an R-Value, multiply the RSI Value by 5.678.

Install insulation under area of roofing to achieve required thickness. Where overall insulation thickness is 2.7 inches (70 mm) or greater, install two or more layers with joints of each succeeding layer staggered from joints of previous layer a minimum of 6 inches (150 mm) in each direction.

Tapered Insulation System for Flat Roof Deck: Install insulation as follows:

Minimum total thickness of Continuous Insulation: 5.2 inches.

Minimum thickness of base layer: 2.6 inches.

Minimum thickness of each subsequent layer: 2.6 inches.

Minimum Continuous Insulation R-value: Not less than 30.

Retain below if required for Project. Insulation drain sumps are allowed to taper down to a thickness of not less than 1 inch (25 mm) less than the thickness required to achieve the continuous insulation thickness required by code. The size of the sump is further dictated by the slope. For example: A 1-inch (25 mm) deep sump at 1/4 per foot (1:48) slope would have a size of 4 ft. by 4 ft (1200 by 1200 mm). To accommodate larger and/or deeper sumps, increase total insulation thickness as necessary.

Insulation Drain Sumps: Tapered insulation sumps, not less than 2 by 2 feet (600 by 600 mm), sloped to roof drain. Sump to maximum depth or not more than 1 inch (25 mm) less than the Project-stipulated continuous insulation thickness based upon code requirements.

Trim surface of insulation where necessary at roof drains so completed surface is flush and does not restrict flow of water.

Install tapered edge strips at perimeter edges of roof that do not terminate at vertical surfaces.

Retain applicable "Insulation Application Method" Paragraph(s) below.

Adhered Insulation Application Method: Install each layer of insulation and adhere to substrate as follows:

Prime substrate with primer as recommended by manufacturer and allow to dry.

Low-Rise Foam and Fas-N-Free are applied in ribbons.

Set each layer of insulation in ribbons of bead-applied insulation adhesive, firmly pressing and maintaining insulation in place.

Cover Board Installation: Install cover boards over insulation with long joints in continuous straight lines with end joints staggered between rows. Offset joints of insulation below a minimum of 6 inches (150 mm) in each direction. Loosely butt cover boards together. Tape joints if required by roofing manufacturer.

Fasten cover boards to resist uplift pressure at corners, perimeter, and field of roof.

Low-Rise Foam and Fas-N-Free are applied in ribbons.

Set cover board in ribbons of bead-applied insulation adhesive, firmly pressing and maintaining cover in place.

Coordinate this Article carefully with Part 2 Product listings; use consistent terminology.

COLD-APPLIED BUILT-UP ROOFING INSTALLATION, GENERAL

Install roofing membrane system according to roofing system manufacturer's written instructions and applicable recommendations in NRCA's "Quality Control Guidelines for the Application of Polymer Modified Bitumen Roofing" and as follows:

Number of Ply Sheets: Four.

Adhering Method: Cold-applied adhesive.

Surfacing Type: A (aggregate).

Start installation of built-up roofing in presence of manufacturer's technical personnel.

Cooperate with testing agencies and personnel engaged or required to perform services for installing roofing.

Coordinate installation of roofing system so insulation and other components of the roofing membrane system not permanently exposed are not subjected to precipitation or left uncovered at the end of the workday or when rain is forecast.

Provide tie-offs at end of each day's work configured as recommended by NRCA Roofing Manual Appendix: Quality Control Guidelines - Insulation to protect new roofing.

Complete terminations and base flashings and provide temporary seals to prevent water from entering completed sections of roofing.

Remove temporary plugs from roof drains at end of each day.

Remove and discard temporary seals before beginning work on adjoining roofing.

Substrate-Joint Penetrations: Prevent roofing asphalt and adhesives from penetrating substrate joints, entering building, or damaging built-up roofing components or adjacent building construction.

ROOFING MEMBRANE INSTALLATION

Install lapped base-ply sheet according to roofing manufacturer's written instructions, starting at low point of roofing system. Extend roofing membrane sheets over and terminate beyond cants, installing as follows:

Adhere to substrate in cold-applied adhesive.

Ply Sheets: Install ply sheets starting at low point of roofing. Align ply sheets without stretching. Shingle side laps of ply sheets uniformly to achieve required number of plies throughout thickness of roofing membrane. Shingle in direction to shed water. Extend ply sheets over and terminate beyond cants.

Embed each ply sheet in cold-applied membrane adhesive applied at rate required by roofing manufacturer, to form a uniform membrane without ply sheets touching.

FLASHING AND STRIPPING INSTALLATION

Install base flashing over cant strips and other sloping and vertical surfaces, at roof edges, and at penetrations through roof, and secure to substrates according to built-up roofing manufacturer's written instructions and as follows:

Extend base flashing up walls or parapets a minimum of 12 inches (300 mm) above built-up roofing and 6 inches (150 mm) onto field of built-up roofing.

Prime substrates with asphalt primer if required by built-up roofing manufacturer.

Flashing Sheet Application: Adhere flashing sheet to substrate in cold-applied adhesive. Apply cold-applied flashing sheet adhesive to back of flashing sheet if recommended by roofing manufacturer. Mechanically fasten top of base flashing securely at terminations and perimeter of roofing.

Flashing Sheet Top Termination: Mechanically fasten top of base flashing securely at terminations and perimeter of roofing.

Seal top termination of base flashing with a metal termination bar and a continuous bead of joint sealant.

Flashing Sheet Bottom Termination: Adhere flashing sheet to roofing membrane in continuous bed of cold-applied adhesive.

Bituminous Flashing: Seal bottom termination of base flashing by adhering to roofing membrane and stripping flashing to membrane joint.

Install stripping, according to roofing manufacturer's written instructions, where metal flanges and edgings are set on built-up roofing.

Flashing-Sheet Stripping: Install flashing-sheet stripping in a continuous coating of compatible mastic/adhesive sealer, as recommended by roofing manufacturer, and extend onto roofing membrane. Apply number of courses recommended by manufacturer.

Roof Drains: Set 30-by-30-inch (760-by-760-mm) metal flashing in bed of compatible mastic/adhesive sealer on completed built-up roofing. Cover metal flashing with built-up roofing cap sheet stripping and extend a minimum of 6 inches (150 mm) beyond edge of metal flashing onto field of built-up roofing. Clamp built-up roofing, metal flashing, and stripping into roof-drain clamping ring.

Install flashing sheet stripping according to roofing manufacturer's written instructions.

SURFACING AND COATING INSTALLATION

Flood Coat and Aggregate Surfacing: Promptly after installing and testing roofing membrane, base flashing, and stripping, flood-coat roof surface with cold-applied adhesive surfacing adhesive applied at rate required by roofing manufacturer.

While adhesive coating is fluid, cast aggregate surfacing in a uniform application at the average weight indicated in Part 2 product listing.

FIELD QUALITY CONTROL

Roofing Inspector: Contractor shall engage a qualified roofing inspector for a minimum of 5 full-time days on site to perform roof tests and inspections and to prepare start up, interim, and final reports. Roofing Inspector's quality assurance inspections shall comply with criteria established in NRCA's "Quality Control and Quality-assurance Guidelines for the Application of Membrane Roofing Systems."

Final Roof Inspection: Arrange for roofing system manufacturer's technical personnel to inspect roofing installation at commencement and upon completion.

Notify Owner's Consultant and Owner 48 hours in advance of date and time of inspection.

Repair or remove and replace components of built-up roofing where test results or inspections indicate that they do not comply with specified requirements.

Additional testing and inspecting, at Contractor's expense, will be performed to determine compliance of replaced or additional work with specified requirements.

PROTECTING AND CLEANING

Protect built-up roofing from damage and wear during remainder of construction period. When remaining construction will not affect or endanger roofing, inspect roofing for deterioration and damage, describing its nature and extent in a written report, with copies to Owner's Consultant and Owner.

Correct deficiencies in or remove built-up roofing that does not comply with requirements, repair substrates, and repair or reinstall roofing to a condition free of damage and deterioration at time of Substantial Completion and according to warranty requirements.

Clean overspray and spillage from adjacent construction using cleaning agents and procedures recommended by manufacturer of affected construction.

END OF SECTION 075113.13