SECTION 07500
MODIFIED BITUMINOUS ROOFING
PART 1 – GENERAL
1.1 PROVISIONS GOVERNING WORK UNDER THIS SECTION
A. GENERAL REQUIREMENTS: See Division 1.
1.2 SUBMITTALS
A. SUBMITTALS:
1. MANUFACTURER’S SPECIFICATION for roofing and base flashing as certification of materials and methods to be used.
B. SUBMIT PRODUCT DATA PER SECTION 01300:
1. INCLUDE Manufacturer’s complete Installation Specifications for roofing system that will be installed, including insulation, built-up roofing, base flashing and gravel guards or roof edge flashings.
2. SUBMITTAL shall include minimum and maximum temperature of each hot applied adhesive for each operation.
1.3 WARRANTY
A. REFERENCE: Section 01700.
1. GUARANTEE: Furnish a written guarantee covering built-up roofing and flashings against leaks and defects due to faulty workmanship or materials for a period of two years from Date of Substantial completion of Building, and furnish written guarantee prior to request for final payment. Guarantee shall be signed jointly by Roofing Subcontractor and Contractor.
2. GUARANTEE required by this Section of Specifications shall apply to roofing, roof insulation and sheet metal work, which is in connection with roofing even though certain work in connection with roofing is installed under other Sections of these Specifications.
1.4 STORAGE OF MATERIALS
A. MATERIALS: Roofing materials, asphalt and other required materials shall be stored and protected as recommended by Supplier.
1.5 JOB CONDITIONS
A. PREROOFING CONFERENCE: Prior to the installation of the roofing and associated work, Contractor shall call a meeting at the Project Site with the Installer, the Installer of each component of associated work, the installers of deck or substrate construction to receive roofing work, the Installers of other work in and around roofing which must follow the roofing work (including mechanical work), the Architect and other representatives directly concerned with the performance of the Work. Contractor shall record the discussions of the conference and the decisions and agreements (or disagreements) reached, and furnish a copy of the record to each party attending. Review foreseeable methods and procedures related to the roofing work, including but not necessarily limited to the following:
1. REVIEW PROJECT REQUIREMENTS (Drawings, Specifications and other contract Documents).
2. REVIEW REQUIRED SUBMITTALS, both completed and yet to be completed.
3. REVIEW STATUS of substrate work (not by the Roofing Installer), including finishing, drying, structural loading limitations and similar considerations.
4. REVIEW availability of materials, tradesmen, equipment and facilities needed to make progress and avoid delays.
5. REVIEW required inspection and accounting procedures.
6. REVIEW WEATHER and forecasted weather conditions, and procedures for complying with unfavorable conditions.
7. REVIEW REGULATIONS concerning safety and similar considerations.
8. REVIEW PROCEDURES needed for protection of stored materials and roofing during the remainder of the construction period.
1.6 RELATED WORK SPECIFIED ELSEWHERE
A. ACCESSORIES: Roof drains and other related work.
B. SHEETMETAL FLASHING AND TRIM: Section 07620. Contractor shall require that sheet metal in conjunction with built-up roofing be furnished and installed by Roofing Subcontractor.
PART 2 – PRODUCTS
2.1 ROOF MATERIALS
A. BASE SHEET: ASTM D4601, Type G-2, Class A.
B. ADHESIVE: ASTM D312, Type II.
C. ASPHALT PRIMER: ASTM D41.
D. BITUMINOUS ROOF CEMENT: ASTM D2822, asphaltic.
E. ELASTOMERIC SEALANT: Sealant shall conform to FS TT-S-00230C, or TT-S-001543A.
F. ROLL ROOFING: GAFGLAS Mineral Surfaced Granule Roll Roofing.
G. FLASHING SHEET: Modified bitumen, such as “Derbigum.”
H. ROOFING SPECIFICATIONS: Apply the following roof application, complying with the Roofing Material Manufacturer’s Specification.
I. APPROVED ROOFING SYSTEMS:
1. GS Roofing Products, Flintlastic CMS, No. GM5-C-B2.
2. Or equivalent as approved by Architect.
PART 3 – EXECUTION
3.1 PREPARATION
A. EXAMINATION AND PREPARATION OF SURFACES:
1. INSTALLER: Examine the areas and conditions under which roofing and insulation work is to be performed and notify the Contractor in writing of conditions detrimental to the proper and timely completion of the Work. Do not proceed with the Work until unsatisfactory conditions have been corrected in a manner acceptable to the Installer.
2. CONDITIONS OF SURFACES: Surfaces of roof decks shall be smooth, dry and free from loose materials. Cants shall be in place in locations where roof surface abuts vertical surfaces and at miscellaneous roof openings. Pipe flashings and roof drains shall be on hand or in place.
3.2 APPLICATION OF ROOFING MEMBRANE
A. MATERIALS: Apply in strict accordance with Manufacturer’s Specifications and Details unless specified otherwise herein.
3.3 ROOFING APPLICATION
A. GENERAL: Place felts per Manufacturer’s Specifications.
B. BROOMING: Broom each felt to set firmly an uniformly without voids, even if not required by Roofing Manufacturer. When brooming felts walk beside felts being broomed, not directly behind broom.
C. TEMPERATURE: Control temperatures in accordance with Manufacturer’s Specifications at all times and for each specific type of adhesive material.
D. THERMOMETERS: Bitumen heating apparatus shall have a thermometer in proper working order at all times, and in addition, a stand-by thermometer in proper working order shall be available on the job.
E. PROTECTION OF ROOF:
1. PLYWOOD: Protect roofing, insulation, and roof deck from damage at all times with plywood sheets, including roof after aggregate has been placed.
2. STACK OR STOCKPILE roofing felts on plywood panels or pallets to protect rigid insulation and steel roof deck from damage.
F. CUT-OFFS: At end of each day’s roofing installation, protect exposed edge of the incomplete work, including ply sheets and insulation, provide two plies felt in full moppings of hot bitumen; remove at beginning of next day’s work.
3.4 FLASHINGS
A. FLASHING:
1. FLASHINGS shall be completed daily, staged flashing application will not be allowed.
2. OTHER flashings not specifically specified herein shall be applied in accordance with manufacturer’s specification and approved by the Architect.
3. SHEET METAL that will come in contact with bituminous materials shall be primed with an asphalt primer and allowed to dry before applying bitumen.
B. BASE FLASHING: Install base flashings at the base of vertical wall and curb surfaces which abut the built-up roof in accordance with the following:
1. PRIME walls with asphaltic primer applied at one gallon/100 sq. ft.
2. INSTALL 4 inch by 4 inch fiberboard cants at the juncture of all vertical surfaces and roof. Cants may be nailed or embedded into hot steep asphalt.
3. AT WOOD surfaces only, embed one-ply of fiberglass felt into hot steep asphalt over the cant strip, extending up the vertical surface and down 2 inches out onto the roof.
4. APPLY one-ply of the modified bitumen flashing sheet in accordance with manufacturer’s specification. The flashing sheet shall be of sufficient width to extend from the top outside edge of the wall or curb (or to the top of the flashing surface where counter flashing is used) a minimum of 2 inches further onto the roof than the preceding ply, or a minimum of 4 inches out onto the roof.
5. FASTEN the top edge of the base flashing approximately 4 inches OC with appropriate fasteners through one inch diameter tin discs.
6. WHERE BASE flashing ends at the vertical, seal the top edge of the flashing with woven fiberglass flashing fabric (six inches wide) embedded into and covered with asphaltic plastic (flashing grade) roof cement, centered over the top edge of the base flashing.
7. COMPLETELY bond all flashing to the underlying surface. Completely bond the flashing plies to each other without looseness, bubbles or voids. Remove and replace loose flashings.
8. COAT the completed base flashing system with aluminum coating.
C. ROOF DRAIN FLASHINGS:
1. TAPER INSULATION to roof drains.
2. DRAIN rings shall be removed prior to insulation and built-up roof application.
3. ONE-PLY OF ROOFING SHALL BE SET INTO ROOF CEMENT AND COVERED BY A 4LB LEAD SHEET, ALSO SET INTO SOLID COATING OF ROOF CEMENT. The lead sheet shall be shaped to conform snugly over the underlying insulation taper. Application of roofing plies will then begin at the drain, making sure to extend all plies, including the lead sheet and underlying ply, into the drain and under the clamping ring.
4. THE DRAIN ring shall be set into asphaltic roof cement and tightened.
D. METAL FLASHINGS: The pipe flashing sleeves shall be set into asphaltic plastic roof cement over the installed roof plies.
1. INSTALL galvanized metal pipe jacks for electrical conduit lines. Set into plastic roof cement and nail securely to treated wood nailers.
2. FLANGES shall be flashed on the roof with two plies of fiberglass felt embedded into hot asphalt. The first ply shall extend a minimum of 3 inches beyond flange onto the roof. The second ply shall extend a minimum of 3 inches further onto the roof than the first ply.
3.5 FIELD QUALITY CONTROL
A. TEST CUTS: The Architect reserves the right to require two test cuts through roofing and insulation, which shall be made when and where directed by an approved Testing Laboratory, replaced and patched back into place. Cuts shall be 4” x 40” and taken with long dimensions perpendicular to roofing felts length. Tale tests before aggregate is applied and in accord with ASTM D3617.
1. PATCHING: Fill cuts with roofing felts set in flashing cement, with three-plies of felt feathered over cut lapping minimum on 6 inches.
2. TESTING LABORATORY SERVICE: Refer to Section 01400.
END OF SECTION
07500 - 1 LK 00000