Each job must be approved by American WeatherStar before the project begins to be eligible for a warranty.

PART 1 – GENERAL

1.01  DESCRIPTION

A.   The Fully Adhered System utilizes TPO membrane bonded to a WeatherStar approved insulation or structural substrate.

B.   One American WeatherStar Approved Applicator shall perform roof application and related work.  A single firm is required so that there is undivided responsibility for the performance of the completed roofing system.

C.   Furnish and install the WeatherStar Fully Adhered Roofing System in strict accordance with drawings and specifications approved by American WeatherStar.

D.   Related Work

The work includes, but is not necessarily limited to, the installation of:

·  Vapor Retarders (where required)

·  Insulation

·  Anchor Bars

·  Polyester Felt

·  Fasteners

·  Roof Membrane

·  Flashing

·  Metal Flashing

·  Wood Nailer

·  Walkways

·  Approved Sealants

·  Adhesives

·  Metal Coping (as required)

·  All metal work to be fastened per Sheet Metal & Air Conditioning Contractors National Association, Inc. standards.

1.02  QUALITY ASSURANCE

A.   The roofing system must be installed by an approved WeatherStar Roofing Applicator for the project to be eligible to receive a manufacturer's system warranty.

B.   There shall be no deviation made from this specification or the detail drawings without written approval from American WeatherStar prior to the start of the roofing project.

C.   Upon completion of the installation, an inspection shall be conducted by a Technical Representative of WeatherStar to ascertain that the roofing system has been installed according to American WeatherStar most current published specifications and details. This inspection is not intended to be a final inspection for the benefit of the owner but, rather, for the benefit of American WeatherStar to determine whether a warranty can be issued.

D.   It is the roofing applicator's responsibility to adhere to all applicable building codes (local and national) for roofing system installation requirements and limitations in his/her geographical area.

E.   For specific code and testing agency approvals achieved by American WeatherStar, refer to the agency's published listings.

1.03  SUBMITTALS

A.   Submit a Pre-Project Inspection Report to American WeatherStar for approval PRIOR to the job start to enable AWS to approve the intended assembly and assign a job number to the project. This submittal may include "deviation request forms" and "pullout test" results, depending on the project criteria.

1.   The Pre-Project Inspection Report MUST be filled out completely and accurately to include any prior deviations approved from this specification.

2.   The Pre-Project Inspection Report must have a roof drawing or shop drawing attached for the project to be assigned a job number. The roof drawing must show: a) the dimensions of the roof system being submitted for warranty coverage, b) the location of all curbs installed during initial application, c) the type and thickness of insulation used in each area, d) the penetration count by either plotting or listing the penetrations installed during the initial application broken down into the various categories, e.g. pipes, drains, pourable sealer pockets, etc. This information is required in order to protect both American WeatherStar and the installing contractor from additional liability for alterations performed to the roof system without WeatherStar's knowledge and involvement. AWS requests a separate roof drawing for each roof assembly type installed on a project. For example, a project consisting of an adhered and a ballasted system would require two separate roof plans; however, if the two different assemblies are on the same building please indicate their proximity to one another on the roof plans for reference purposes.

B.   When Material & Workmanship or Full Systems warranties are desired, American WeatherStar MUST receive the Pre-Project Inspection Report or be contacted PRIOR to project bid and installation. Information may be required for the wind design of the system.

C.   Upon completion of the project the roofing contractor shall notify American WeatherStar of the date of completion and request a final inspection.

D.   Upon completion of the roof inspection by WeatherStar, satisfactory completion of any punch list items, and receipt of applicable warranty fees, the warranty will be issued to the installing contractor.

1.04  PRODUCT DELIVERY, STORAGE AND HANDLING

A.   Deliver materials in original, unopened containers.

B.   Containers shall be labeled with manufacturer's product name and general information.

C.   All materials, even membrane, should be stored between 60°F (16°C) and 80°F (27°C). If exposed to lower temperatures, restore to 60°F (16°C) minimum temperature before using.

D.   Store all materials, including membrane, in a dry, protected area. Damaged materials must not be used. Installed materials found to be damaged shall be replaced at contractor's expense.

E.   Protect the membrane from abuse or damage during storage.

F.   Protect all stored materials from inclement weather by covering with breathable tarpaulins until ready to install. Use caution to properly anchor or weigh down the weather protection to prevent wind related damage.

G.   Improperly stored insulation that has been allowed to get wet shall not be used in a warranted roof system and shall be replaced at the contractor's expense. In cases where the wet insulation is isolated to only a few boards per bundle, only those boards that have been wet must be replaced. Failure to replace insulation boards that have been exposed to moisture can result in bowing or curling insulation as the material dries unevenly while in the roof system and may adversely affect the dimensional stability of the insulation material. In either case, the removal and replacement of the affected insulation will be the responsibility of the installing contractor as a punch list item or under their two-year obligation if discovered after the initial inspection but within 24 months of warranty issuance.

1.05  JOB CONDITIONS (CAUTIONS AND WARNINGS)

A.   Do not use oil or bituminous base roof cement with TPO materials.

B.   Do not install TPO membrane directly in contact with new or re-saturated asphalt.

C.   Do not expose membrane or accessories to temperatures of 180°F (82°C) or above.

D.   Do not allow waste products (petroleum grease, oil or solvents, etc.) or direct steam venting to come in contact with TPO materials. Any exposures not typical for normal roofing installation must be presented to American WeatherStar for assessment of any impact on the performance of the roofing system.

E.   Do not install WeatherStar membrane directly in contact with coal tar roof surfaces.

F.   When using an insulation / underlayment attachment method other than mechanical securement with fasteners of an approved type, size and length there may be additional factors to take into consideration. The primary issues to consider include:

1.   The products involved and the performance of asphalt attachment and insulation adhesive by others will not be included in the system warranty coverage due to being products supplied by others. Separate warranty coverage may be available from the manufacturer of the product being used but is separate from the WeatherStar Warranty Coverage and must be pursued by the installing contractor or property owner.

2.   For insulation / underlayment attachment methods other than loose laid for ballasted systems and mechanically anchored to WeatherStar specification for adhered and mechanically attached systems, the maximum allowed board size is 4' x 4'.

3.   When using Insulation Adhesive it is imperative to verify that the approved substrate has not been altered by coatings, sealants or additives.

NOTE:  Alteration of the bonding substrate voids warranty coverage for the attachment of the insulation unless prior written approval is received from WeatherStar before the application commences.

G.   Cold weather application of adhesives and sealants requires special consideration. As specified in the Product Delivery, Storage and Handling section above, the roofing adhesives, solvents, caulks and sealants must be stored at service temperatures ranging from 60°F (16°C) and 80°F (27°C) prior to use.

1.   If a room temperature storage environment is not available these products must be restored to serviceable temperatures before application by alternate means such as hot boxes, pail warmers, etc. and rotated as required to maintain a serviceable installation temperature throughout the application process.

2.   During periods of high humidity, especially at cooler temperatures, it is essential to be aware of the possibility of condensation forming on the surface of the adhesives. This is referred to as "blushing". It occurs when the dew point is near the ambient outside temperature and is caused by the evaporation cooling process inherent in the flashing of solvents. This condition is more prevalent on foggy or overcast days. Once blushing begins, work must be stopped until conditions improve. During cold weather, it is important to work in smaller areas, allow longer flash-off times and try to limit application of solvent based adhesives and sealants to the warmest hours of the work period possible.

3.   Solvent based adhesives tend to surface-flash during cold weather, forming an outer skin on the surface before the entire adhesive layer has had sufficient time to flash off. When this occurs it is imperative that the adhesive is allowed to flash off properly to the correct application condition. To determine if the applied adhesive has surface-flashed conduct a "push" test of the prepared surface by touching the adhesive film with your finger (away from any seam edges) and push to see if your finger slides through any un-flashed adhesive. If a surface skin condition is identified, allow extra time for the adhesive film to properly flash off before re-testing. In extreme cases of surface curing, it may be necessary to allow the adhesive film to completely cure overnight and to re-apply the adhesive and start over when better working conditions exist. Mating two surfaces together that have suffered surface curing of the adhesive will result in blisters and bubbles in the membrane application, caused by the trapped solvent from the uncured adhesive.

4.   Under no circumstances should laying of membrane, or application of adhesives, primers, or caulks take place during periods of any form of precipitation.

H.   Cold weather application of TPO membranes requires special consideration.

1.   Thermoplastic membrane roofs are assembled with hot air welded seams using electric powered hot air welders. Cold weather applications require extra attention to ambient conditions in that fluctuations in temperature and wind can adversely affect the welding parameters established at the beginning of the work day.

2.   During a cold weather application, it is important to re-establish welding parameters after every break in hot air welding, e.g. lunch, at the beginning of each work day, etc. by conducting a welding test on some scrap membrane in order to get the welding equipment set up correctly for the current conditions.

1.06 WARRANTY

A.   American WeatherStar warrants that the material supplied will meet or exceed physical properties as published. The contractor guarantees that workmanship will be free of defects in coating application. Since performance of existing roof substrate is beyond the control of American WeatherStar or the contractor, requests for additional warranty coverage shall be subject to prior approval by American WeatherStar.

B.   Comply with manufacturer's warranty application procedures. A Pre-Project Inspection Report should be submitted and approved prior to job commencement.

1.07  ACCEPTABLE STRUCTURAL ROOF DECKS

American WeatherStar has compiled a list of the most common deck types found in the construction field. American WeatherStar strongly recommends that you review its requirements and restrictions PRIOR to each roofing project.  Refer to the following table.

Table 1 - New Construction or Tear Off to Deck

Deck Type	Conditions	Special Requirements (if any)
Steel Deck	22 gauge min.	24 - 28 gauge requires submission of pull test results to determine acceptability (less than 28 gauge not acceptable).
Structural Concrete	3000 psi (20.7 MPa) min.	If using Insulation Adhesive to bond to the concrete, the concrete must not be sealed, coated or contain additives (e.g. curing accelerants) without approval from WeatherStar.
Lumber	3/4" (1.9 cm) min.	Requires submission of pull test results to determine acceptability. Refer to Table 5.
Plywood	15/32" (1.2 cm) min.	Must be APA approved material and be fastened with screws to the supporting structure. Requires submission of pull test results to determine acceptability - Table 5.
Concrete Plank	2" (5.1 cm) min.	Use caution if drilling in concrete plank to avoid spalling. Requires submission of pull test results to determine acceptability. Refer to Table 5.
Cementitious Wood Fiber	N/A	Requires submission of pull test results to determine acceptability. Refer to Table 5.
Gypsum Deck	Poured in place or plank	Requires submission of pull test results to determine acceptability. Refer to Table 5.
Lightweight Concrete	N/A	Requires submission of pull test results to determine acceptability. Refer to Table 5. When used as a substrate for an Adhered or Mechanically Attached System, securement must be made though the lightweight concrete and into the structural deck.

1.08  ACCEPTABLE ROOF SYSTEM SUBSTRATES

An acceptable substrate will provide a smooth surface capable of fully supporting a WeatherStar roof assembly and anticipated roof loads. When used to support an adhered roof system, with either mechanically attached or bonded insulation to the deck, the acceptable insulation substrate must also possess sufficient structural integrity to secure the roofing membrane to the structure when the membrane is bonded to it. Thermal value to the roof assembly, when applicable, must also be considered when choosing an insulation substrate. When insulation is used as a roof substrate, the insulation must be capable of being supported by the structural deck, i.e. a typical steel deck would not support wood fiber alone but would support an isocyanurate insulation board with a wood fiber overlay. A suitable substrate can be an existing roof surface, a structural deck or insulation as detailed in the following table.

Table 2 - Immediate Substrate Types

Immediate Substrate Type	Conditions for use as an Immediate Roof System Substrate
Plywood or Wood Plank Decks	American WeatherStar TPO may be installed directly over plywood, provided the substrate is free of contamination, sharp edges and protrusions. Wood plank decks require an approved minimum thickness insulation board. The bondable substrate, whether plywood or minimum thickness insulation, must not have voids greater than 1/4" between panels. Voids between panels of plywood or insulation greater than 1/4" in width must be filled with a suitable material to provide a smooth, bondable surface. Where plywood is used as a direct substrate, the plywood should be attached to the structural support with screw type fasteners, in lieu of nailing, to prevent damage caused by fastener back out as the structure moves due to expansion/contraction and settling. Damage caused by building movement is excluded from warranty coverage.
Steel Deck (22 Gauge min.)	An approved minimum thickness of insulation board must be used. Insulation shall be mechanically fastened with appropriate fasteners and plates. Contact WeatherStar for alternative methods to attach insulation to metal decks.
Structural Concrete or Concrete Plank	An approved minimum thickness insulation board is required. Insulation can be mechanically fastened with appropriate fasteners and plates or fastened using alternate methods of insulation securement. Insulation Adhesive is approved for securement when system specifications call for attachment provided the deck has not been altered by coatings, sealants or curing accelerants. Asphalt attachment is accepted in some cases for insulation securement but is not covered by the WeatherStar Warranty.
Lightweight Concrete, Cementitious Wood Fiber or Gypsum	Lightweight concrete, cementitious wood fiber and gypsum decks must be overlaid with a minimum thickness layer of approved insulation secured directly into the lightweight deck provided acceptable pullout values are achieved with an NTB Fastener and insulation plate. Alternate methods of insulation securement include securing the insulation through the lightweight concrete directly to the structural deck or installing a mechanically attached base sheet and mopping in the insulation. Insulation may also be attached to cementitious wood fiber decks with Low Rise Insulation Adhesive.
Existing Gravel Surface BUR and Coal Tar Pitch	All loose gravel must be removed or leveled to ensure a relatively flat substrate. An approved minimum thickness insulation board is required and must comply with system requirements for the roof assembly being installed.
Smooth Surface BUR or Modify APP/SBS Roof System	For adhered systems, the existing smooth surfaced BUR must be overlaid with a minimum thickness approved insulation acceptable for use with adhered systems secured in accordance with the WeatherStar published fastening requirements for any given insulation type. For all other EPDM and TPO (not PVC) Systems, the membrane may be attached directly over smooth surface BUR without a separator sheet or insulation board, provided no fresh bituminous roof cement or asphalt base products have been used on BUR surface or will come in contact with the roofing membrane. When the condition of a smooth surface BUR or Modified Bitumen roof prevents the use of the existing roof as a direct substrate for an EPDM or TPO Roof System, a separator sheet may be used to smooth the BUR or Modified Bitumen surface to an acceptable level. Please consult WeatherStar regarding suitability of using a separator sheet versus insulation. PVC may be installed directly over Smooth surface BUR or Modified Bitumen, provided a Polymat is used as a separator between the PVC and existing asphalt system.
Existing Single-Ply Membrane Roofs – All Types	In re-roof situations that involve leaving the existing Single-ply membrane in place, the existing membrane must be cut into 10' x10' pieces and then overlaid with an acceptable rigid insulation board to ensure that the original roof membrane is isolated from the new WeatherStar Single-Ply Roof System. The rigid board type and mechanical securement of the insulation must comply with the securement requirements of the new roof system being installed.

 

Table 3 - Acceptable Insulations

Insulation Type	Minimum Thickness	Acceptable for Use on These Systems:
Isocyanurate	1" (2.5 cm) min. *1 1/2" (3.8 cm) min.	All (1)
Wood Fiber	1" (2.5 cm) min. for Std. 1/2" (1.3 cm) min for High Density	All (1)
Perlite	3/4" (2.5 cm) min.	Ballasted Only (1)
Polystyrene (Expanded or Extruded)	1" (2.5 cm) min.	All (1 & 2)
Gypsum Board	1/4" (overlay only) 1/2"	All (1)

NOTES:  1. Insulation thickness must be minimum thickness required by manufacturer to span openings in the deck. In some cases, it may be necessary to use a support layer of insulation.

               2.  Except Ballast, Expanded and Extruded Polystyrene insulation must be 1 lb. minimum density and be overlaid with acceptable coverboard. Contact WeatherStar for other options with Expanded and Extruded Polystyrene insulations.

1.09 ACCEPTABLE FASTENERS

Warranted WeatherStar Roof Systems must be assembled using WeatherStar approved fasteners of appropriate type and length installed at the rate specified in the insulation attachment, and if applicable, the membrane attachment portion of the Installation Section of this specification. The application rate of fasteners specified in the sections mentioned above is based on an approved deck providing 300 lb minimum pullout resistance. For projects with decks requiring pullout testing, a completed pull out test result form is required with the Pre-Project Inspection Report.

Table 4 - WeatherStar Approved Fastener Application Guide

Fastener Type	Approved Accessories	Insulation Attachment	Membrane Attachment	Deck Types	Codes*
#12 Fastener	1	Yes	No	Steel, Wood	N/A
#14 Fastener	1,4,5,6	Yes	Yes	Steel, Wood	N/A
#15 WH Fastener	1,5,7	Yes	Yes	Steel, Wood, Concrete	FM I-90 with seam plate #7 secured at 12" o.c., FM I-60 secured at 18" o.c.
#16 MAX Fastener	7,10	No	Yes	Steel, Wood,	FM I-90 with seam plate #12 secured at 12" o.c., FM I‑60 secured at 18" o.c.
#12 Preassembled	N/A	Yes	No	Steel, Wood	N/A
#15 Preassembled	N/A	Yes	Yes	Steel, Wood, Concrete	FM I-90 with seam plate #7 when spaced 12" o.c.
CD-10 Concrete Fastener	1,4,5,6	Yes	Yes	Concrete	FM I-90 with seam plate #7 when spaced 12" o.c.
Light Deck Screw	2,8	Yes	Yes	Gypsum, Cementitious Wood Fiber	N/A
Purlin Screw	5,6	Yes	Yes	Steel Purlins	N/A
NTB Plastic Auger (w/ or w/o wire)	3,9	Yes	Yes	Gypsum, Cementitious Wood Fiber	N/A

*See list below for accessory codes. Assemblies must consist of listed components in order to meet referenced rating.

Insulation Plate Options:    " 3" Insulation Plate                            " 3" Lite Deck Insulation Plate Membrane Securement Options:    " 3" NTB Steel Plate                           " 2" Round Steel Seam Plate    " WH 2 3/8" Seam Plate                     " Metal Anchor Bar    " Polymer Batten Strip                        " Light Deck Anchor Bar    " 2" NTB Steel Plate                           " 3" MAX Seam Plate The codes listed above are only a partial representation of the codes achieved by American WeatherStar. Please contact WeatherStar if you have any code related questions regarding assemblies not referenced. NOTE: 1. Fasteners shall be corrosion resistant coated and comply with Factory Mutual Standard 4470. 2. Insulation fasteners shall be suitable for the insulation used. 3. All screw type fasteners shall be a minimum #14 shank diameter for membrane securement. 4. No hex head fasteners are permitted for insulation or membrane securement in WeatherStar warranted systems. American WeatherStar requires a pullout test to be conducted by an independent agency on the following types of decks and the results submitted to WeatherStar prior to project bid: Gypsum, Cementitious Wood Fiber, Oriented Strand Board, Lightweight Concrete, Concrete Plank Deck and any Metal Decks lighter than 22 gauge. Fully adhered applications on decks providing less than the required 300 lbs. of pullout resistance may still qualify for warranty coverage if the insulation is secured in accordance with the supplemental securement table on the following page contingent on WeatherStar approval. Roof Size                                                            Pullout Test Requirements Less than 10,000 ft2 (929 m2)................................................. 6 10,000 ft2 - 50,000 ft2 (929 m2 - 4645 m2)............................... 10 50,000 ft2  - 100,000 ft2 (4645 m2 - 9290 m2).......................... 20 Over 100,000 ft2 (9290 m2)................................... 1 per 5,000 ft2 (464.5 m2) CAUTION: Use appropriate fastener for substrate.

 

1.10  WOOD NAILERS

Wood nailers provide a termination point for roofing insulation as well as a securement point to tie the roof system into the building shell. Wood nailers are not covered by the WeatherStar warranty because they are a product by others and considered part of the building structure. Following are WeatherStar's requirements for wood nailers:

A.   Wood nailers are required at all roof edges where gravel stop metalwork, drip edges or gutter systems are specified. The width of the nailer must exceed the width of the flange of any metalwork mounted to it and be of equal thickness to the roof insulation in order to protect the edge of the insulation and provide a substrate to anchor the metalwork to, without impeding drainage. Wood nailers are also required under any roof top curbs that are not mounted directly to the structural deck with the same width and thickness requirements stated above.

B.   Wood Nailers must be #2 Grade or better lumber. Wood treated with preservatives containing creosote, asphalt, pentachlorophenol, copper naphthenate, copper 8-quinolinolate, and alkaline copper quatenaries (ACQ) have an adverse effect on single-ply roofing membranes and are not acceptable for use in a WeatherStar Roofing System.

C.   In all cases, the wood nailer must be anchored to the deck in an industry accepted method to the designing architect's specification. As a minimum standard the treated wood nailers must be anchored sufficiently to resist 200 pounds (889 N) of force  per linear foot in any direction with fasteners spaced not more than 24" (60 cm) apart. Refer to the Perimeter Flashing portion of Factory Loss Prevention Data 1-49 (June 1985) for nailer securement recommendations. Wood nailers are not part of the WeatherStar Roofing System and, therefore, not covered by the WeatherStar warranty.