NEW ELECTRICAL SUBSTATION Building 300 SECTION ETHYLENE-PROPYLENE-DIENE-MONOMER ROOFING WORK

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1 ETHYLENE-PROPYLENE-DIENE-MONOMER ROOFING WORK 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. ASTM INTERNATIONAL (ASTM) ASTM D 4637 EPDM Sheet Used in Single-Ply Roof Membrane 1.2 SUBMITTALS Government approval is required for submittals with a G designation. Submit the following in accordance with Section SUBMITTAL PROCEDURES: SD-03 Product Data EPDM (Bearing) Sheet G EPDM Cover Strip G Membrane Cleaner G Primer G Lap Sealant G SD-08 Manufacturer s Instructions EPDM Cover Strip G Membrane Cleaner G Primer G Lap Sealant G Page 1 of 6

2 1.3 DELIVERY, STORAGE, AND HANDLING Delivery Deliver materials in their original, unopened containers or wrappings with labels intact and legible. Where materials are covered by a referenced specification number, the labels must bear the specification number, type, class, and shelf life expiration date where applicable. Deliver materials in sufficient quantity to allow continuity of work Storage Store and protect materials from damage and weather in accordance with manufacturer s printed instructions, except as specified otherwise. Keep materials clean and dry. Store and maintain liquid materials above 60 degrees F. Mark and remove damaged materials from the site. Use pallets to support and canvas tarpaulins to completely cover material stored outdoors. Do not use polyethylene as a covering. Locate materials temporarily stored on the roof in approved areas, and distribute the load to stay within the live load limits of the roof construction. Remove unused materials from the roof at the end of each days work 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. Do not use materials contaminated by exposure or moisture. Remove contaminated materials from the site. When hazardous materials are involved, adhere to the special precautions of the manufacturer. 1.4 ENVIRONMENTAL REQUIREMENTS Do not install EPDM products during high winds or inclement weather, or when there is ice, frost, moisture, or visible dampness on the substrate surface, or when condensation develops on surfaces during application. Unless recommended otherwise by the EPDM sheet manufacturer and approved by the Contracting Officer, do not install EPDM sheet when air temperature is below 40 degrees F or within 5 degrees F of the dewpoint. 1.5 SEQUENCING Coordinate the work with other trades to ensure that cover strips are installed as the work progresses. Unless otherwise approved by the Contracting Officer, only cut as much of the existing EPDM roofing as can be sealed with new cover strips in the same work day. If EPDM membrane cuts are permitted to remain without permanent seals (cover strips) beyond the end of the work day, ensure that temporary protection measures are in place to preclude moisture intrusion or damage to the building or installed materials. Page 2 of 6

3 1.6 EXISTING ROOF AND WARRANTY The existing roofing in the area of the work is a loose laid and ballasted.060 inch thick Johns Manville EPDM membrane roofing system over ½ thick protection board and 3 inch thick (2 layers) of loose laid insulation board on a concrete deck supported by metal decking and sloped steel beams. The roofing system was installed in 1992 and is under warranty until Accordingly, all EPDM roofing work required by this specification and as indicated on the drawings shall be executed in a manner which maintains the current roof warranty. In the case of conflict between the requirements of this specification or the accompanying drawings and the manufacturer s requirements for maintenance of the roof warranty relative to the work to be done under this contract, the manufacturer s requirements shall take precedence. PART 2 PRODUCTS 2.1 MATERIALS EPDM (Bearing) Sheets Ethylene Propylene Diene Terpolymer (EDPM), ASTM D 4637, Type I, non-reinforced, inch nominal thickness. The minimum thickness must not be less than minus 10 percent of the specified thickness value. EPDM membrane thickness specified is exclusive of backing material on the EPDM membrane. Principal polymer used in manufacture of the membrane sheet must be greater than 95 percent EPDM EPDM Cover Strips EPDM Cover Strips shall be the self-adhering type and must be.060 inch minimum total thickness composed of cured EPDM with an integral full pressure sensitive adhesive backing, as recommended by the roof membrane manufacturer Membrane Cleaner Membrane cleaner shall be a type suitable for use on existing, weathered EPDM roofing and as recommended by the EPDM manufacturer Primer Primer shall be a type suitable for use on existing aged EPDM roofing and as recommended by the EPDM manufacturer. Page 3 of 6

4 2.1.5 Lap Sealant Edge Treatment Lap sealant shall be as supplied and recommended by the EPDM manufacturer. PART 3 EXECUTION 3.1 PREPARATION FOR ROOFING WORK Perform the following work and ensure the following conditions exist prior to the application of the roofing materials: a. Temporarily remove and store existing stone ballast and roof walkpads. Removals shall be as indicated and as needed to permit the proper application of the new EPDM cover strips and bearing sheets at the locations indicated. Existing stone ballast shall be removed by use of a gravel pusher or push broom. Use of rakes or shovels is not permitted. b. Neatly cut existing EPDM roofing and flashing at the locations indicated and remove and dispose of underlying protection board and roof insulation to the extent needed for installation of new wood sleepers and cants. c. Ensure that new pressure preservative treated wood sleepers and cants are securely fastened in place. Ensure that top surfaces of sleepers are flush with the top surface of the existing protection board on the roof. Ensure that cants are installed at the angle between the roof and concrete curb and that the angle of the cant is 45 degrees and the height of the vertical leg of the cant is not less than 3-1/2 inches or otherwise matches the existing cant. Ensure that warped or split wood has been replaced and that there are no cracks or end joints ¼ inch in width or greater. Ensure that all fasteners through sleepers and cants are properly set and that countersunk holes have been filled. d. Ensure substrate is sloped to provide positive drainage. e. Ensure surfaces to which new roofing materials are to be applied are rigid, clean, dry, smooth and free from cracks, holes and sharp changes in elevation. 3.2 APPLICATION Apply roofing materials as indicated and specified herein unless approved otherwise by the Contracting Officer Special Precautions Page 4 of 6

5 a. Do not dilute liquid materials unless specifically recommended by the materials manufacturer s printed application instructions. Do not thin liquid materials with cleaners used for cleaning EPDM sheet. b. Keep liquids in airtight containers, and keep containers closed except when removing materials c. Use liquid components within their shelf life period. Store at 60 to 80 degrees F prior to use. Mix and use liquid components in accordance with label directions and manufacturer s printed instructions. d. Provide clean, dry cloths or pads for applying membrane cleaners and cleaning of membrane. e. Do not use heat guns or open flame to expedite drying of primers. f. Require workmen and others who walk on the membrane to wear clean, softsoled shoes to avoid damage to roofing materials. g. Do not use equipment with sharp edges which could puncture the EPDM sheet EPDM (Cover Strips and Bearing Sheets) Provide watertight roof membrane strips and sheets free of contaminants and defects that might affect serviceability. Provide uniform, straight, and flat edges. Unroll EPDM membrane in position without stretching membrane. Inspect for holes. Remove sections of EPDM membrane that are damaged. Allow strips and sheets to relax a minimum of 30 minutes before adhering or application of subsequent construction Cover Strips Prior to application of cover strips, clean and prime the underlying existing EPDM roof membrane in accordance with the manufacturer s recommendations and instructions using products specifically designed for use on aged or weathered EPDM membrane. Allow primer to dry or set in accordance with the membrane manufacturer s instructions prior to application of the cover strips. Set EPDM cover strips into position and check for proper overlap and position. Cover strips shall be 12 inches wide as indicated, shall overlap the underlying cuts in the existing EPDM roof membrane by a minimum of 3 inches on all sides, and shall extend to the underside of the existing metal sandwich wall panels at the penthouse concrete curb. Corners of cover strips shall be cut round. Peel off protective release liner from the cover strip and press down the exposed tape adhesive using hand pressure over the entire cover strip, then immediately roll across, not parallel Page 5 of 6

6 to, the cover strip edge with a steel roller in accordance with the manufacturer s instructions. Apply lap sealant to all cover strip edges Bearing Sheets Provide for protection of roof membrane by placing temporary EPDM membrane bearing sheets at all surface bearing support locations (wood sleepers) for the temporary staging platform as indicated. Bearing sheets shall be loose laid over the new cover strips and removed after installation of the substation is completed Roof Walkpads Reinstall walkpads in original locations after removal of temporary staging platforms and EPDM membrane bearing sheets Ballast Reinstall (push back) existing stone ballast to cover all new cover strips after removal of temporary staging platforms and EPDM membrane bearing sheets and reinstallation of walkpads. Use a gravel pusher or broom to move ballast. Use of rakes and shovels is not permitted. --End of Section-- Page 6 of 6