J01a Specifications.pdf

FLEXIBLE SHEET ROOFING SYSTEM SPECIFICATIONS

1.0 GENERAL

A. Requirements

1. The Roofing contractor shall be aware that this is an active Health Care Center project and that the Health Center is to remain in business without interruption during the course of the project. Daily communication with the assigned Health Center facilities management staff to coordinate the reroofing efforts shall be required.

2. The contractor shall make allowance in his bid for providing and installing two hundred and fifty (250) 30 inch by 60 inch Roofing Manufacturers walk pads. The

Hospital shall direct where these are to be installed.

3. At the onset of the project the contractor shall meet with the Parker Indian Health

Center facilities management staff to identify any rooftop equipment to be removed prior to or in conjunction with the roof project. The contractor shall then prepare the roof by cutting and fastening down any buckling, refastening any loose fastening and generally cleaning the roof of any debris in preparation for the installation of the new roof system.

4. In those areas to be overlaid the contractor shall furnish and install an approved rollout underlayment prior to installation of the new roof system.

5. Contractor shall furnish and install a 50 mil single-ply membrane roofing system that is fabricated of a weft inserted low-shrink, anti-wicking polyester fabric and has a

Polyvinyl chloride coating (PVC) material laminated to both sides as manufactured by Duro-Last Roofing, Inc., or approved equal.

1.1 GENERAL CONDITIONS

A. Requirements of the Membrane Manufacturer

1. There shall be no deviation made from this specification without prior written approval the building owner or his/her duly appointed representative.

2. Manufacturer may be asked to submit an audited document listing the long-term warranty liability commitment of manufacturer.

3. Provide primary flexible sheet factory prefabricated roofing system from a single manufacturer that has successfully manufactured raw materials into the submitted specified products for not less than five (5) years. Provide secondary materials, such as insulation, DensDeck Roof Board, vapor barriers, etc. as recommended and approved by manufacturer of primary materials.

4. Products, primary and secondary, shall be manufactured in the United States of

America.

FLEXIBLE SHEET ROOFING SYSTEM

B. Field Inspection

The contractor shall arrange for the Roofing Manufacturer to provide inspection of the roofing system installation. Upon completion of the installation, an inspection shall be made by a Quality Assurance Specialist of the membrane manufacturer at no extra charge to the building owner or contractor. The inspection is to ascertain that the visible elements of the roofing system have been installed in accordance with the membrane manufacturer’s published specifications and details.

C. Defective Work

Should the installation of the roofing system not be approved by the Roofing Membrane

Manufacturer, correcting the defective work shall be done by the contractor until the roofing system satisfactorily meets all the specifications and manufacturer’s requirements. Corrective work will be done at NO ADDITIONAL EXPENSE TO THE

OWNER.

D. Guarantees

1. The warranty shall be full roofing system repair and/or replacement fifteen (15) year warranty covering materials and labor. The warranty shall be a no-dollar limit type and provide for completion of repairs, replacement of membrane or total replacement of the “roofing system” at the then current material and labor prices throughout the life of the warranty.

2. Warranty shall be issued by the original manufacturer of the roofing membrane.

3. No work shall be done on said roof, including but without limitations, openings made for flues, vents, drains, sign braces, or other equipment fastened to or set on the roof, unless the Contractor or membrane manufacturer is notified first. Contractor or membrane manufacturer shall be given the opportunity to make the necessary roofing application recommendations with respect thereto, and require such recommendations are complied with. Failure to observe this condition shall render the warranty null and void. The contractor or membrane manufacturer shall be paid for time and material expended in making repairs occasioned by the work of others on said roof.

4. Corrective measures on leaks shall be undertaken within seventy-two (72) hours after notification has been received by the Contractor or Membrane Manufacturer from the

Owner. Telephone & email are acceptable forms of communication for the purposes of notification.

E. Weight Requirements

The total weight of the installed roofing system including all accessories, i.e: screws, plates, 2-way breather vents, etc., shall not exceed 30 pounds per square foot.

2.0 PRODUCTS

A. Manufacturer

1. The following CPA manufacturer has been pre-approved for this project, Duro-Last

Roofing, Inc.

2. Fire resistance of CPA roofing system shall meet UL Class A. All packaging of membrane and insulation shall bear UL Class A label.

3. Membrane color shall be white, tan, or gray selected from manufacturer’s samples by the Indian Health Service Facilities Management Staff.

2.1 MATERIALS

A. Membrane-Related Materials

1. All membrane components, including pipe and curb flashings must be factory prefabricated from the same fabric reinforced material used for the deck membrane.

2. Termination Sealant: Compatible with materials to which membrane is to be bonded, conforming to Federal Specifications TT-598 and TT-S-00230C as furnished by the membrane manufacturer.

3. Distribution Plates: Factory Mutual approved stress distribution plates formed from a minimum 24 gauge G-90 C.Q. steel with a galvalume coating for insulation attachment, or 20 gauge G-90-C.Q. steel with galvalume coating or high strength polyblend for membrane attachment.

4. Water Cut-Off Mastic: Compatible with materials with which it is used and furnished by the membrane manufacturer.

5. Pitch Pocket Sealant: Shall be a single component, self-leveling silicone sealant furnished by the membrane manufacturer.

6. Fasteners: Compatible with roof deck as furnished by the membrane manufacturer.

Fasteners shall be coated and furnished by the membrane manufacturer; they must pass 30 cycles in the Kesternich Cabinet, DIN #50018-2 Liter. The FM approved fastener is inserted through the hole in the distribution plate and properly secured to the roof deck.

7. Breather Vents: Two-way vents with factory-attached skirt shall be installed at a density of one per 1,000 square feet of roof deck area and in accordance with the membrane manufacturer’s specifications.

8. Terminations/Edge Details: Shall be manufactured from rigid exterior vinyl with slotted holes for securement and furnished by membrane manufacturer with a vinyl coated drip edge on all perimeter mansard wall and courtyard terminations. All other terminations/edge details must be approved and warranted by roofing membrane manufacturer.

9. Walkway Pads: Provide membrane manufacturer walkway pads made from the roofing membrane material installed in strict compliance with manufacturer’s recommendations. Pads shall be non-skid, maintenance free, and restrained to remain in position. Walkway pads shall be a contrasting color to the roof membrane. Owner and/or Owner’s representative shall choose from standard color samples.

B. Insulation

The minimum underlayment shall be 3/8 inch pad.

C. Tapered Crickets (where required)

Crickets shall be formed of tapered material having the same requirements and characteristics as listed in the preceding paragraph.

D. Roofing Nails

Nails shall be galvanized “Stronghold” type: (for use on parapet walls, wood nailers).

E. Nailers & Blocking

1. Where required, nailers and wood blocking shall be S4S 1500 fc construction grade

Douglas fir conforming to standard 15 grading and dressing rules of the West Coast

Lumber Inspection Bureau, or other species of wood of equal strength. All lumber shall be grade marked at the mill.

2. All lumber shall be non pressure treated by a method approved by the roofing membrane manufacturer.

3. Nailers shall be securely anchored to the deck to resist the minimum force required in

Loss Prevention Data Sheet I-49, “Perimeter Flashing,” Factory Mutual Systems, June, 1985. The thickness of the nailer shall be such that the top of the nailer is flush with the surface to which the membrane is to be applied.

F. Accessories

Primary accessories shall be factory prefabricated or manufactured by or under the direction of the membrane manufacturer. All other shall be approved by the roofing membrane manufacturer.

3.0 EXECUTION

A. Substrate Inspection

1. Inspect all surfaces to receive roofing for any condition that will adversely affect execution, performance, or quality of work.

2. All roof surfaces and all sloped surfaces to drains and outlets shall be checked and approved by the roofing contractor prior to the start of the roofing work.

3. Install roofing material only under satisfactory conditions as specified by the roofing membrane manufacturer.

4. Scheduling: Schedule the roofing work in areas and sections in such a manner as to keep the new and existing insulation, roofing materials, and building absolutely dry and watertight during new roofing work.

5. Any damage sustained to the facility or contents as a result of improper scheduling of roofing work shall be the contractor’s responsibility.

B. Surface Preparation

Contractor’s proposal shall include all costs for the removal of wet or damaged existing roofing insulation and replacement as required, repair of blisters, existing flashings, expansion and control joint covers, and repair or replacement of required treated wood nailers or blocking.

1. The total extent of preparation shall include the above and comply with the roofing membrane manufacturer’s recommendations.

2. Mechanically secure separation material units to roofing deck independent of membrane attachment and cover immediately with membrane. Butt units tightly together, limiting joint separation to 1/8 inch, maximum.

3.1 GENERAL REQUIREMENTS

A. Precautions

1. Do not lay out or expose any insulation on the deck that cannot be covered by membrane on the same day.

2. In making all field heat welds, make sure all edges are clean and free of tar, mastic or other foreign items.

3. Do not expose membrane and accessories to a constant temperature in excess of 110 degrees Fahrenheit.

4. Sealants and adhesives should be applied according to the manufacturer’s specifications and all containers shall be disposed of properly.

5. Start securing the membrane at the highest point and work towards the drains.

B. Protection of Roofing Surfaces

Storing, wheeling, or trucking directly on roof insulation or membrane surface is not allowed. Smooth, clean plywood or plank walkways, runways and platforms shall be provided as necessary.

3.2 MEMBRANE INSTALLATION

A. Roof Sections

Unfold first sheet along edge of roof or parapet wall. Position and fasten first tab with plates and screws according to membrane manufacturer specifications. Unfold roofing sheet to the second 3-1/4 inch wide fastening tab. Pull tab tight and secure to deck as herein described, maintaining proper plate and screw frequency, squarely placed.

Continue unfolding and fastening roofing membrane until entire sheet is in place. Install the adjacent roofing membrane sheets using the fastening procedure described. Proceed until all sheets are in place, thus forming a monolithic roof cover. Make sure all edges of each sheet of roofing are fastened with the same fastener spacing as tabs or are welded to another sheet that is fastened in this manner.

B. Field Welding

All field heat seams of the roofing materials shall be 1-1/2 inch wide minimum and be made with a hot air welder. The hot air welder shall be in such a position so that the outside edge and both pieces of material will receive an equal amount of heat and all of which will be closely followed by a 1-5/8 inch wide roller specially designed for this purpose. Make a hands and knees inspection of all field welds with a probe.

C. Perimeter Nailing

The membrane shall be mechanically fastened at all roof perimeters, parapets, curbs, wall, penetrations, etc. in strict accordance with the Contract Documents and specifications and details.

D. Cut-Outs

Make cut-outs in roofing membrane for protrusions through the roof. Some situations might require that the deck membrane be slit to the section edge for fitting around protrusions. Fasten around cut-outs with approved fasteners, 12 inches on center or a minimum of one per side. The skirts on factory prefabricated accessories when welded to deck will cover these.

E. Stacks

After membrane has been attached, select proper size of premanufactured round stack for roof vents and pipes. Drop stack flashing over the pipe, lay flat to the roof, and heat weld the skirt to the deck membrane. Using appropriate hand tool, tighten stainless steel band

(or stainless steel screw clamp) around top of stack flashing to prevent water penetration, and cut off excess. Using factory approved sealant, liberally seal the top of the stack flashing and steel band.

F. Custom Curbs/Pitch Pockets

After securing cut-out as stated, heat weld the bottom of the skirt to the deck membrane.

If the square or rectangle penetration has a removable top, i.e. roof hatch, skylight, etc., remove the unit and fold the custom curb flashing over the top, secure, then replace unit.

If top is not removable, secure the top of the custom curb flashing with termination bar and seal with factory approved sealant. Use this same procedure on existing or new pitch pockets.

G. Breather Vents

Install a two-way breather vent for every 1,000 square feet of deck area. Factory prefabricated vents with a skirt made from roofing membrane shall be used. For new construction or reroof after tear-off, a 2-1/2 inch diameter hole cut down through the roofing membrane and insulation facer is required. For recover/non-tear-off application a

2-1/2 inch diameter hole is to be cut through the roofing membrane and the facer down to the facer on the existing insulation. Heat weld skirt to the deck membrane so as to position two-way vent directly over the hole. Careful placement of the breather vents must be observed. DO NOT locate in valleys, next to roof penetrations, scuppers, roof drains, etc. Equally space the vents throughout the roof area. Do not fasten the vent or the skirt to the roof deck. This two-way breather vent is designed to vent the roofing system only and not the building to which it is installed.

H. Parapet Walls

Fasten bottom tab of prefabricated parapet wall flashing 12 inches on center with approved fasteners. This fastening sequence will secure both bottom of parapet and edge of deck membrane. Base skirt should extend approximately 6 inches onto the roof. This allows for a 1-1/2 inch wide weld and covering of the fasteners and plates. Heat weld skirt to deck membrane. On all termination bar applications, start fastening at one end and proceed to the other. This will eliminate buckling of the termination bar. Seal behind the parapet wall material and on top of termination bar with factory approved sealant. If parapet wall coping is to be covered, extend covering down 2 inches on exterior face of coping and terminate accordingly.

I. Roof Drains

1. Secure cut-out made in deck membrane with four (4) equally spaced fasteners and distribution plates. If drain is flush with deck, use a prefabricated drain boot. Apply factory-approved sealant all around drain approximately 12 inches under deck membrane and install the expanding snap rings.

2. If the roof drain has a secure clamping ring and strainer, unbolt and remove. Clean and apply factory-approved sealant under deck membrane around drain for use as a water block seal after cutting properly sized hole. Secure clamping ring and strainer to drain base over deck membrane. Seal with factory approved sealant between clamping ring and roofing membrane.

J. Expansion Joints/Valleys

1. Whenever encompassing an elevated mid-roof expansion joint, must use a prefabricated expansion joint section. Prior to the installation of the expansion joint flashing the contractor is to drape and fasten approved rollout underlayment (Nova

Rollout, or equal) over the expansion joint. This section shall allow loose layment over the joint and approved fastening on either side. A 6 inch skirt on both sides of the membrane flashing will provide coverage of fasteners and still allow approximately 1-1/2 inch for a heat weld to deck membrane.

2. Valleys are worked in the same manner. Fasten according to specifications, 12 inches on center, and lap deck membrane over fasteners. Heat weld deck membrane to valley section.

K. Roof Tie-Ins

When terminating the roofing membrane onto an existing roof, care must be taken to stop any water from backing under the new deck membrane.

3.3 INSPECTION & WARRANTY

A. Manufactures roofing Quality Assurance Technician, roofing contractor shall conduct all required inspections. Submit all required drawings, details, and completed questionnaires to the roofing manufacturer before obtaining the specified warranty. After an authorized

Quality Assurance Technician has inspected the roof for determining acceptability for warranty issuance, deficiencies on the final inspection report shall be corrected by the contractor/applicator and made ready for re-inspection.

B. Warranty: Upon receipt of required materials, certifying inspection, and acceptance of the roofing system by the roofing membrane manufacturer, the warranty shall be duly executed and issued to the Owner.

3.4 CONSTRUCTION DAMAGE

Upon completion of work, repair or replace as required, all building materials damaged as a result of the roofing operations. Match existing materials as close as possible. Owner and/or Owner’s representative will approve the selection of matching materials.

END OF SECTION