1. GENERAL REQUIREMENTS
    1. Roof designs require the approval of the University’s insurance underwriter.  Coordinate submittal with OSU’s Project Manager.
    2. Roof repair and replacement projects within the OSU National Historic District will likely require an approved HPP application.
    3. Indicate applicable American Society for Testing and Materials (ASTM) specification in this section.
      1. Fire resistance shall be based on ASTM E-108
    4. Indicate applicable Oregon Structural Specialty Code, latest edition
    5. Indicate applicable Underwriters’ Laboratory (UL)
      1. Fire resistance based on UL- 790
    6. Indicate applicable the university’s insurance underwriter specifications
      1. Wind uplift criteria based on the university’s insurance underwriter
    7. Indicate applicable National Roofing Contractors Association standards.
    8. No new clay tiles roof are permitted
    9. All work described in this standard shall comply with the current editions of the codes as adopted by the local jurisdiction and the latest edition of the International Building Code
    10. Waterproofing systems shall be used at all building planters, plaza decks, and penthouse and mechanical equipment.
    11. Any and all overflow drainage from roof shall be managed in accordance with applicable municipal code requirements.
    12. Moisture control:
      1. Install condensation control/ vapor retarders as required per the needs of the roof system.
      2. All attic and/ or under deck ventilation shall be installed as required to control moisture.
    13. Testing for water tightness and material performance may be required at OSU’s discretion prior to OSU’s acceptance of roofing and drainage systems. Obtain acceptance of testing method from Owner and roofing materials manufacturer.
    14. Refer to OSU Construction Standard 22 30 00 for additional information on Roof Drains.

  2. FALL PROTECTION
    1. All roofs requiring maintenance must have fall protection from one of the following methods, or a combination thereof:
      1. Parapet wall [preferred] 42” per OSHA building codes.
      2. Guardrails [minimize visibility of the guard rails from the ground or adjacent buildings]
      3. Tie-offs [provide specialized equipment and access from roof hatches]
        1. Structures of four stories or greater shall be equipped with roof tie off systems that allow for routine window cleaning on those stories four stories or greater.

  3. MANUFACTURER QUALIFICATIONS
    1. The Manufacturer’s Roof System Warranty shall include: Single source not less than 20 years, No Dollar Limit (NDL), for labor and material for entire system, including the roof system and other related systems.
    2. Manufacturer shall have manufactured products continuously by same company for a period of time not less than ten years.
    3. Manufacturer shall not be in any form of bankruptcy.
    4. Manufacturer shall be the primary manufacturer of the membrane system.

  4. ROOFING
    1. All roof designs and specifications shall be reviewed and approved by OSU’s Project Manager & Facilities Services.
      1. All roof projects completed in the OSU National Historic District must be coordinated with the University Land Use Planning unit of Capital Planning and Development.
    2. The existing architecture of the building shall be accommodated.
    3. Install attic draft stops as required by Building Code.
    4. For renovations, all roofs shall be provided with code compliant fall protection systems parapet, railing, or tie-offs.
    5. For new construction, mechanical equipment located on roof must be screened by the parapet or screen wall or installed in a penthouse.
    6. All roofs require access for maintenance of equipment, roof drains, etc.
      1. Provide walking/tread pads from point(s) of egress to the roof to point(s) requiring maintenance. The walk pads shall be placed in the design, such that all locations requiring maintenance are accessible from the walking surfaces. 
      2. The walking tread pad material must be manufactured by the roof system manufacturer.
    7. All roofs shall be constructed or installed in a manner that provides for positive drainage without ponding or the occurrence of standing water to a drain per all applicable building code requirements and related specifications and standards.

  5. ROOF INSULATION
    1. Provide separation board suitable for attachment to structure to provide a base for roofing or insulation and to provide for required fire ratings.
    2. All insulation assembly shall meet thermal and fire rating requirements and shall be approved in writing by the roofing manufacturer.
    3. Insulation overlay shall be designed and suitable for the roofing material.

  6. DRAINAGE
    1. Provide required slopes to primary roof drain in structure, unless otherwise approved by OSU’s Project Manager.
    2. Provide tapered insulation and crickets as required to achieve drainage requirements.
    3. Ballasted extruded polystyrene inverted insulation system shall meet the university’s insurance underwriter and UP UL requirements.
    4. Install vapor retarder, as required, as part of the roofing assembly.
    5. Fasten, adhere, stagger, offset to provide a proper base for roofing and to meet the university’s insurance underwriter and UL requirements.
    6. All fasteners shall be increased by 50% in number at all perimeter locations and at corners.
    7. Insulation R-Value shall be 20% better than the requirement of the current Oregon Energy Code.

  7. LOW SLOPE ROOFING
    1. Applied Locations
      1. Use on low slope concrete, steel, wood or insulated roof decks.
      2. Minimum ¼” per foot slope to maximum 1” per foot slope to drain.  ½” per foot is preferred.
      3. Other slopes may be considered and approved by OSU’s Project Manager, if necessary.
      4. Special securement may be required on slopes exceeding ½” per foot.
      5. Roofing material needs to be coved up above overflow drains.
    2. Applications
      1. Elastomeric Membrane Roofing:
        1. Provide Vapor Barrier appropriate to roofing system.
        2. Substrate: Separation board, insulation system, overlay board assembly as required to meet all codes, including (energy, wind uplift, and fire rating), and to meet manufacturer requirements for suitable roofing base.
        3. Material: EPDM (Ethylene Propylene Diene Monomer) fire rated 60 mils minimum thickness in largest sheets possible.
        4. Application: Fully adhered
        5. Terminations: All perimeters and roof penetrations at vertical surfaces.
      2. Modified Bituminous Membrane Roofing
        1. Provide Vapor Barrier appropriate to roofing system
        2. Substrate: Insulation system, overlay board assembly as required to meet all codes, including (energy, wind uplift, and fire rating), and to meet manufacturer requirements for suitable roofing base.
        3. Material: SBS (Styrene-Butadiene-Styrene)
        4. Application: Cold Adhesive
    3. Seams
      1. Protective Coating: Elastomeric as approved by membrane manufacturer.
    4. Standards
      1. NRCA Roofing and Waterproofing Manual – TS Series Specification Guides.
      2. ASTM – Standard Specifications for material Properties.
      3. UL – Fire Hazard Clarifications, Class A.
      4. The university’s insurance underwriter Roof Assembly Classifications.
      5. OSSC, Chapter 15 – Roof Assemblies and Rooftop Structures.
      6. Approved Manufacturers: Siplast, Carlisle and Firestone or approved equal.
    5. Hot Asphalt Roofing
      1. Use of new hot asphalt roofing system is not allowed on new and replacement roofs. Major repairs for hot asphalt roofing systems – must plan and mitigate for odors entering building air intakes, building windows and/or adjacent buildings as needed. University’s representative to confer with EH&S on mitigation plan prior to work being commenced.

  8. METAL ROOFING
    1. Applied Locations
      1. Use on low slope framing and steel or wood roof decks, minimum three inch (3”) per foot slope.
      2. System: Sealed standing seams with concealed fastening and provision for expansion and contraction.
      3. Precoated Galvanized Steel: 24 gauge minimum core steel, G90 galvanized, Kynar coated.
      4. Underlayment: Rosin paper slip sheet, 30# asphalt saturated felt and rosin paper, self-adhering underlayment, special underlayments when required by design or manufacturer’s insulation system.
      5. Standards
        1. NRCA Roofing and Waterproofing Manual – Metal Roof Systems.
        2. ASTM D226 – Standard Specification for Asphalt Saturated Roofing Felt.
        3. ASTM B370 – Standard Specification for Copper Sheet and Strip.
        4. ASTM A361 – Standard Specification for Zinc Coated Steel Sheet.
        5. ASTM A308 – Standard Specification for Terne Coated Steel.
        6. ASTM C1167 – Standard Specification for Clay Tile.
        7. ASTM UL580 – Tested for Wind Uplift, Class 90 Rated.
        8. ASTMSMACNA Architectural Sheet Metal Manual.
      6. System
        1. Standing seams or approved design with concealed fastening system; provisions for expansion and contraction.
      7. Warranty:
        1. Provide 50-year Manufacturer’s warranty
        2. Manufacturer’s standard warranty for color

  9. STEEP ROOFING
    1. Applied Locations
      1. Use on steep slope wood roof decks, minimum three inch (3”) per foot pitch.
    2. Materials
      1. Shingles
        1. Self-sealing Architectural asphalt or SBS (Styrene-Butadiene-Styrene) modified bitumen, polyester/fiberglass or fiberglass reinforced, mineral granule surfacing, minimum 245# per 100 square feet, CertainTeed Grand Manor or approved.
        2. Shingle shall be moss protected and have minimum 50-year manufacturer’s warranty.
      2. Underlayment
        1. 30# asphalt saturated roofing felt or breathable underlayment as approved by OSU’s Project Manager
        2. 1 layer for pitches of 4:12 and steeper
        3. 2 layers for pitches of 3:12 to 4:12
        4. Self-adhering underlayment for pitches less than 3:12
        5. Self-adhering underlayment at all valleys, eaves and rakes
        6. Pitches of less than 4:12 are not recommended.
      3. Standards
        1. NRCA (National Roofing Contractors Association) Roofing and Waterproofing Manual – Application of Asphalt Shingles.
        2. ASTM D226 – Standard Specification for Asphalt Saturated Roofing Felt.
        3. ASTM D3462 – Standard Specification for Asphalt Shingles.
      4. Warranty
        1. Manufacturer’s standard 50 year material warranty
        2. Manufacturer’s standard warranty for color
      5. Provide ventilation under sheathing as required by code.
      6. Insulation
        1. Insulation is not permitted directly below shingles.
        2. Insulation to be designed and constructed to allow roofing material to function properly throughout warranty period.

  10. FLASHING AND COUNTERFLASHING
    1. Systems
      1. Flashing and counterflashings, gutters and downspouts, copings, wall metal as required for the application.
      2. Standing, water shedding, sealed and soldered seams as required for the application.
      3. Expansion joints or other provisions for expansion as required.
      4. Back metal with felt as required.
    2. Materials: As required by application, compatible with roofing materials.
      1. Metals
        1. Precoated Galvanized Steel: 24 gauge minimum core steel, G90 galvanized, Kynar coated.
        2. Terne Coated Carbon Steel: Gauge as required for application.
        3. Terne Coated Stainless Steel: Thickness as required for application.
        4. Stainless Steel: Thickness as required for application.
        5. Copper: Sixteen (16) ounce minimum.
        6. Lead: Four (4) pound.
      2. Underlayment
        1. 30# asphalt saturated roofing felt and rosin paper.
        2. 15# where approved by OSU
        3. Other breathable underlayment as approved by OSU and self-adhering underlayment.
      3. Warranty
        1. Two-year installation warranty after final acceptance
Last Updated: 
07/17/2018