TECHNICAL
BULLETINS

AEP SPAN TECHNICAL BULLETINS
TABLE OF CONTENTS

TECHNICAL BULLETINS
Technical Bulletin #1	Oil Canning	2-3
Technical Bulletin #2	Recommended Sealants and Usage	4
Technical Bulletin #3	Out of Plane Substrate	5
Technical Bulletin #4	Fasteners in Treated Wood	6
Technical Bulletin #5	Addressing Snow and Ice	7-8
Technical Bulletin #6	Fall Restraints and Metal Roofing	9
Technical Bulletin #7	Roofing Underlayments	10-11
Technical Bulletin #8	Lightning Protection Systems	12
Technical Bulletin #9	Preventing Storage Corrosion	13
Technical Bulletin #10	Touch-Up Paint	14
Technical Bulletin #11	Roof System Care and Maintenance	15
Technical Bulletin #12	Wall System Care and Maintenance	16
Technical Bulletin #13	Cleaning Coil Coatings	17
Technical Bulletin #14	Removal of Stubborn Stains, Sealants, and Peel Coat	18
Technical Bulletin #15	Peel Coat Guidelines and Best Practices	19
Technical Bulletin #16	Reflectance	20
Technical Bulletin #17	Dissimilar Metals	21
Technical Bulletin #18	Zinc in the Rainwater Runoff from ZINCALUME® Roofs	22-23
Technical Bulletin #35	Prestige Series Clip.	24

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AEP SPAN TECHNICAL BULLETIN #1
OIL CANNING

DESCRIPTION
Oil Canning is an inherent characteristic of light gauge cold formed metal products, particularly products with broad flat areas. It is a visual phenomenon seen as waviness or distortion in the flat surfaces of metal roofing and siding products. Oil canning is subjective and is normally an aesthetic concern
only and does not affect a products strength or performance. Environmental conditions such as temperature, time of day, annual seasons, amount and angle of sunlight (sunny vs. cloudy) can effect the appearance of oil canning.

CAUSES OF OIL CANNING
Oil canning is caused by internal stresses within thin gauge metals. These stresses can be introduced during production of the coil and fabrication of the panels. Additionally, field installation conditions, installation techniques and construction tolerances can greatly impact the presence of oil canning.
Thin gauge materials will not straighten out or compensate for irregular substrates or misaligned framing members.

Metal Coil Production: The process to transform steel into coil form can contribute to oil canning.

Panel Fabrication: The process of transforming steel coils into panels can induce oil canning.

Misalignment Of Support System: A support system with large tolerances may cause stresses on the panels as they are fixed to this surface. This stress on the panels can cause oil canning.

Over Engagement Of Panels: Most panels allow for expansion and contraction by flexing of webs and slight room at the side joints. If the panels are pulled or pushed
during engagement more than designed, the stress will cause deflection in the flat pan of the panel.

Over Driving Of Fasteners: This operation causes stresses on the panel, particularly with concealed fastened panels connected directly into the support system. In addition, if the fasteners are not driven into the panels or clips at the same level of tension, normal expansion and contraction of the panels due to regular temperature changes can amplify visual waviness. This waviness caused by thermal forces (expansion and contraction) can appear and disappear daily as the sun rises and sets.

Movement Of Primary Structure: If the primary structure of the building has excessive variation in deflection, racking, or drift, it can cause waviness in the flat of the panel, once installed. In addition, settlement of the primary structure can also cause oil canning. This oil canning could be temporary or permanent.

Handling Of Panels: The manner in which the panels are handled in the field can induce oil canning. Twisting the panels while lifting and removing from a bundle can induce a wavy appearance. Walking on panels can also cause oil canning.

CONTROLLING OR MINIMIZING OIL CANNING
Coils:
Purchase quality coil stock within acceptable industry standards and tolerances.

Panel Production:
Use sharpened and properly aligned slitting blades.
Use tension leveler prior to roll forming.
Keep roll forming equipment properly adjusted.
Maintain a quality check for profile dimensions and angularity
Provide proper handling, packaging, & transportation.

Design Options:
Specify thicker gauge materials such as 22, 20, or 18 gauge vs. 24 gauge.
Utilize narrow width panels or trim profiles
Add striations or stiffening ribs in the flat of the panel or trim profiles.
Specify low gloss paint finishes. Metallic colors tend to have a higher gloss and could emphasize waviness.
Provide provisions to accommodate thermal stresses such as use of fasteners and clips that allow for expansion and contraction.
Provide proper substrate for attachment.
Orientation of panels (vertical vs. horizontal) may reduce the visual appearance of the waviness in the panels.

Installation:
Properly align framing and assure the substrate is in- plane.
Properly store and handle all materials.
Follow approved Shop Drawing Details and industry standards.
Only use materials supplied and/or approved by the manufacturer.
Use proper installation tools, equipment, and techniques, including fasteners.
Consider installing a foam backer rod to the back middle of flat surfaces to “pillow” the face.

FIELD CHECKING PANEL FLATNESS
There is no accepted Standard for field checking questioned flatness or oil canning. The following is a reasonable means to help determine the probable source or cause of oil canning. The intent is to systematically investigate the field conditions, handling, and installation process observing when the oil canning appears and therefore its most likely source or cause.

Examine the storage area and condition of the crated or packaged materials. Are the materials in a dry protected
location, properly supported and retained in a natural manner that does not induce unusual twist or stress on the materials? OBSERVE
Remove a panel or two from its packaging. Orient it horizontally; allowing it to hang down on its side yet supported along its top rib approximately every 8 to 10 feet by workers or other aligned supports. OBSERVE

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AEP SPAN TECHNICAL BULLETIN #1
OIL CANNING

Have the panel(s) transported in the normal manner, both horizontally and vertically, to the location where they will be installed. OBSERVE
Lay the panel(s) flat and loosely on the substrate to which they will be installed without any clips or other means of attachment. OBSERVE
Install panel into (or on to) already installed adjoining panel. OBSERVE

Install clips/fasteners as required and fasten appropriately to the substrate. OBSERVE

With close and judicious observation, one should be able to determine at which step(s) oil canning first appeared, if any subsequent step(s) changed its appearance, and what possible steps may be initiated to minimize its presence.

IN SUMMARY
Oil canning is an aesthetic issue that is subjectively identified and evaluated. System performance and structural integrity are not affected unless the distortion is extreme. Since many uncontrollable factors are involved in inducing oil canning, no manufacturer can assure the total elimination of oil canning. Oil
canning is not a cause for rejection. However, if attention is paid to the selection of material, panel design and installation practice, oil canning can be reduced or mitigated.

If oil canning is a concern or issue discovered in the field, please contact your sales representative before moving forward on your installation.
References:
Metal Construction Association Technical Bulletin #95-1060, January 2003
American Iron & Steel Institute. “Sheet Steel Coils & Cut Lengths” Steel Products Manual, Oct. 1979
US Steel Sheet & Strip Handbook. July 1983
ASTM E 1514 - 93 Standard Specification for Structural Standing Seam Roof Panel Systems

AEP SPAN TECHNICAL BULLETIN #2
RECOMMENDED SEALANTS & USAGE

INTRODUCTION
This technical bulletin addresses the specific use and application of the three primary types of sealants used in the installation of AEP Span steel roof and wall products.

NON-SKINNING/NON-CURING BUTYL SEALANT
These types of sealants are used purposely in metal roofing and siding applications because panel joints and laps create a very thin space between the materials that are subject to continual dynamic movements which will subject the sealant to shear force. Only a non-skinning, non-curing sealant can perform under such extreme conditions as these types of sealant will never cure or harden over the life of the roof or siding.

Butyl sealants should only be used where dynamic movement of the material will take place due to thermal expansion and contraction and are not subjected to exposure to ultra violet light. UV light will break down these types of sealants overtime making them impractical in exposed applications.

Recommended sealants in this group include, but are not limited to, the following:

PTI® 707
SikaLastomer®-511
Pecora® BA-98
TremPro® JS-773
Acryl-R® SM5430

EXTRUDED BUTYL TAPE
These types of sealants are used in a similar fashion to the non-skinning/non-curing sealants as butyl tape will never cure or harden over its lifetime. Butyl tapes main use is for high infiltration areas such as under the joggle cleat at the eave or
valley condition or in areas where a continuous aggressive bead of sealant is recommended such as used to seal the top and bottom of the zee closures on ridge or peak condition.

Butyl tape is also recommended at the side lap condition of through-fastened (corrugated) panels due to the fact that gun grade sealants are impractical and messy to apply in a thick continuous bead. Like nonskinning/non-curing sealants, Butyl tape should never be used in applications that are subjected to UV exposure. UV light will break down the sealant overtime. Varying sizes of butyl tape are available in the market. The following sizes are available from AEP Span.

Please consult the appropriate panel installation guide or AEP Span representative for appropriate size recommendations.

3⁄32” thick x 3⁄8” wide
1⁄16” thick x 1⁄2” wide
1⁄16” thick x 1⁄4” wide
1⁄8” thick x 1” wide
3⁄16” thick x 7⁄8” wide

CURING SEALANTS
This group of sealants fall into two categories,Urethane and Siliconized. These types of sealants require a specific mass of material, cures relatively hard, and will easily fail when subjected to shear and dynamic forces. AEP Span recommends urethane and siliconized sealant only for non- moving joinery and perimeter seals that are exposed to sunlight and require a curing UV resistant sealant.

It should be noted that although these sealant are recommended for use on AEP Span roof and wall products their use should be limited, as most of AEP Span details utilize concealed gun grade Non-skinning/Non-curing butyl sealants or butyl tape sealants.

Recommended sealants in this group include, but are not limited to, the following:

Urethane Sealant
MasterSeal® NP 1™
Sikaflex®-201 US
Sikaflex®-1a
Dynatrol® I-XL
Dymonic® FC

Siliconized Sealant
Dow Corning® 795 Silicone Building Sealant
Titebond® Weathermaster® Metal Roof Sealant

All of the sealants listed in this letter have specific uses and applications. Please consult our Technical Department or AEP Span Representative for questions concerning specific use and applications or if a sealant not listed needs to be reviewed for use on AEP Span supplied materials.

PTI is a registered trademark of H.B. Fuller Licensing & Financing, Inc. SikaLastomer and SikaFlex are registered trademarks of Sika AG. Pecora and Dynatrol are registered trademarks of Wambold Corporation.
TremPro and Dymonic are registered trademarks of Tremco Incorporation. Acryl-R is a registered trademark of Illinois Tool Works Inc.
MasterSeal is a registered trademark and NP 1 is a trademark of Construction Research & Technology GMBH.
Dow Corning is a registered trademark of Dow Corning Corporation.
Titebond and WeatherMaster is a registered trademark of Franklin International, Inc.

AEP SPAN TECHNICAL BULLETIN #3
OUT OF PLANE SUBSTRATE

OUT OF PLANE SUBSTRATE IMPACTS
There are three fundamental areas affected by an out-of-plane metal roof or wall substrate; aesthetics, thermal movement, and performance.

Aesthetics
The first issue with an out-of-plane substrate deals with aesthetics. Any unevenness or undulations in the roof or wall substrate will telegraph through the metal panels and may cause an unpleasant exterior appearance. This can accentuate oil canning and give a wavy appearance along the length of the metal panels.

Thermal Movement
The next concern is that an uneven substrate could interfere with the panel’s ability to expand and contract under thermal loads. This is particularly an issue with concealed fastener metal roof and wall panels that utilize concealed clips for attachment. These clips are designed for installation on a relatively flat plane. An out-of-plane substrate could cause binding points at clip locations. This can create an unwanted point of fixity and could prohibit the panel from expanding and contracting normally. Expansion and contraction should not be impeded; due to high thermal forces, panel expansion and contraction will still occur, even if the clips are bound
or restricted at uneven areas of the roof or wall substrate.
The thermal movement forces could result in clip failure or complete panel disengagement from the substrate if the shear resistance of the clip and/or clip fasteners is compromised.

Performance
The last concern deals with wind uplift performance. If metal roof or wall panels are installed on an out-of-plane substrate, there is the potential for improper panel-to-clip engagement at the panel side laps. If the panel interlock is not engaged properly the wind uplift performance of the panels could be
impacted. This has the potential to create significant problems with a metal roof or wall panel’s ability to resist wind uplift pressure. Improper panel side lap engagement can also affect air and water infiltration resistance which can compromise the environmental performance of the roof or wall system as well.

GUIDELINES
Common industry guidelines have established that roof substrates should not exceed the following limits for out-of-plane conditions:
1⁄4 inch in 20 feet
1⁄2 inch across building elevation
1⁄8 inch in 5 feet

ASTM E 1514, “Standard Specification for Structural Standing Seam Steel Roof Panel Systems”, also addresses substrate requirements. Section 5.1.2 within states, “Deflection and serviceability shall be accounted for. The deflection shall be limited so as to allow the roof to perform as designed. The substrate deflection shall not cause strains to the panels that affect serviceability of the system.”

The “transfer of ownership” clauses in project contracts are becoming a significant factor in recent times with regards to out-of-plane or deflected substrates. Addressing out-of-plane substrates is of vital importance.

SOLUTIONS
When a metal roof and/or wall subcontractor takes over the substrate and commences their scope of work, typically there is meant to be an inspection by a qualified representative. The subcontractor should be authorized to accept the substrate
or reject questionable areas that may need reworking by the appropriate previously responsible trade.

If subcontractors fail to do this and start installing metal roof or wall panels, they are essentially accepting whatever conditions they are given with no recourse. Additional labor costs may be incurred to correct other trades’ substrate installation issues. Inconsistent substrate joints, seams and framing will almost always transfer through to the metal roof or wall panels and create a kaleidoscope of issues which the installer becomes responsible for at their expense.

A possible corrective action to resolve out-of-plane conditions with minimal impact to the substrate or metal panels is to use shims under the panel clips. 1⁄4" thick shims of plywood can be cut into 4" X 6" squares – sized similar to a panel clip bearing plate, and layered under the clips to even out the clip line with the rest of the substrate areas. Multiple shims may be required depending on the extent of the unevenness of the substrate.

The fasteners will need to be long enough to go through the shims and penetrate the substrate as originally designed. If installed properly, and the uneven area is made level with the rest of the roof or wall, there should be no impact to installed panel aesthetics, thermal movement, or system performance. Manufacturer warranties should also remain intact.

The corrective action above only applies to panels that have the ability to span open framing as the shims lift the panel off the substrate thereby creating a spaced framing condition. The plywood shim method is acceptable for use on all AEP Span roof and wall panels with the exception of Select Seam. Select Seam requires a continuously solid substrate for installation and cannot span open framing.

The corrective action above or any alternate solutions shall be reviewed and approved by the design professional overseeing the project to determine if they are acceptable. Other materials and/or techniques may be required for resolving out-of-plane conditions if the above plywood shim option is not acceptable.

AEP SPAN TECHNICAL BULLETIN #4
FASTENERS IN TREATED WOOD

HISTORY
Since the early 1930’s, the lumber industry has been using a chemical solution known as Chromated Copper Arsnate (CCA) as the primary preservative in its production of pressure treated lumber used in commercial and residential applications. The purpose of pressure treating wood was to prevent premature wood failures due to insect infestations and deterioration due to rot. After many decades of use, the Environmental Protection Agency (EPA) cited the arsenic and chromium contained
in CCA as possible human and environmental hazards. In response, the lumber industry voluntarily ceased manufacturing pressure treated lumber with the CCA preservative in 2004.
After that, several alternative preservatives, such as Alkaline Copper Quaternary (ACQ) and Copper Azole (CA), were introduced as the new generation of wood preservatives.
These were found to be equally toxic to insects and provide resistance to mold and rot.

There were both gains and losses with this change. The gains were obvious with the elimination of the hazardous arsenic and chromium compounds. The key loss is that these new preservative solutions contain a significant increase in their copper levels. Copper is known to be extremely corrosive when in contact with certain metals such as carbon steel, aluminum, or zinc. These metals are dissimilar to copper
and will create a galvanic reaction when in contact and in the presence of moisture. Therefore, ZINCALUME® zinc-aluminum metallic coated panels, and galvanized (zinc) coated panels are very vulnerable to this increased potential for corrosion. alvanized steel clips and fasteners also at pose a high corrosion risk.

The change in wood preservatives and the associated increase in corrosion potential was a major concern nd challenge
for the construction industry. The initial response by some manufacturers, as well as consultants and trade organizations, was to recommend that asphalted barrier coatings be applied to any metals contacting this new generation of treated lumber. In addition, that all fasteners be changed over to an austenitic (300 series) stainless steel. These responses were not welcomed by many in the industry because of the added product and installation costs.

Widespread industry testing over the years has confirmed that the new generation of ACQ and CA treated lumber is in fact highly corrosive and some form of additional protection
absolutely required. Aluminum, was found to be highly reactive with treated lumber. In the case of both ZINCALUME® and galvanized coated products, even when post-painted, a protective barrier of self-adhered bitumen membrane (ice & water shield type material) is recommended between them and the treated lumber. Minimally, a 30# felt membrane that is complete and uncompromised could be used if permanently secured and moisture, including condensation, is reasonably absent. Direct contact with any treated lumber voids all of AEP Span’s paint and material warranties.

FASTENERS
Fasteners are susceptible to high levels of corrosion due to their significant contact with treated lumber. The general consensus within the industry is that austenitic (300 series)
stainless steel fasteners should be utilized when fastening to lumber treated with copper based preservatives. Epoxy coated, proprietary coated fasteners specifically for treated lumber,
and hot dip galvanized fasteners may be alternative solutions; most are generally not considered to provide the same level of protection as stainless fasteners. All fastener selection and attachment should be carefully evaluated for the applications for which they are to be used.

Some alternative wood preservatives are in use that have less corrosive compounds, notably inorganic boron (SBX), and micronized copper (MCQ). Although the risk of galvanic corrosion is potentially reduced, the above fastener recommendations remain.

THE IBC PRESCRIPTIVE REQUIREMENTS FOR TREATED WOOD FASTENERS ARE AS FOLLOWS
2304.10.5.1 Fasteners And Connectors For Preservative-Treated Wood.

“Fasteners, including nuts and washers, in contact with preservative-treated wood shall be of hot-dipped zinccoated galvanized steel, stainless steel, silicon bronze or copper.
Fasteners other than nails, timber rivets, wood screws and lag screws shall be permitted to be of mechanically deposited zinc coated steel with coating weights in accordance with ASTM B 695, Class 55 minimum.
Connectors that are used in exterior applications and in contact with preservative treated wood shall have coating types and weights in accordance with the treated wood or connector manufacturer's recommendations. In the
absence of manufacturer's recommendations, a minimum of Fasteners in Treated Wood ASTM A 653, Type G185 zinc- coated galvanized steel, or equivalent, shall be used.

Exception: Plain carbon steel fasteners, including nuts and washers, in SBX/DOT and zinc borate preservative- treated wood in an interior, dry environment shall be permitted.”

In lieu of code-approved alternatives, IBC requires the fasteners to be of stainless steel, or a hot dip galvanized construction (the additionally noted silicon bronze and copper fasteners are not compatible with coated steel roof and wall products).

IN SUMMARY
AEP Span requires all panels to be isolated from pressure treated lumber using a self-adhered bitumen membrane, or similar barrier, to avoid galvanic corrosion. Fasteners should be of 300 series stainless steel. Alternative fastener
materials/ protective coatings should be carefully considered to confirm their appropriate usage in specific applications.

AEP SPAN TECHNICAL BULLETIN #5
ADDRESSING SNOW & ICE

INTRODUCTION
The purpose of this technical bulletin is to provide a basic review of snow & ice retaining systems and heat tape systems and present AEP Span’s position regarding their use. This document also presents some of the aspects design professionals should consider when developing a project design.

THERE ARE TWO SCHOOLS OF THOUGHT REGARDING THE RETENTION OF SNOW & ICE ON ROOFS
Do Not Retain: This approach requires that the roof be
designed so that the snow & ice can melt and naturally exit off the roof. Careful attention should be used in configuring the building to prevent or minimize the possibility of retaining large accumulations of snow & ice on the roof. Also, the roof configuration itself should direct sliding snow or ice melt from discharging over entrances and walkways or other critical areas such as ground equipment and landscaping.

Retain: This approach intends to retain the snow & ice on the roof until it melts and exits the roof in a controlled manner. One concern of this approach is that amassing large accumulations of snow or ice could represent a dangerous potential should the snow & ice retaining system suddenly fail, be structurally inadequate, or be in a diminished condition due to lack of maintenance, improper installation, etc. A sudden release of large amounts of snow & ice accumulation could be dangerous, or even deadly.

COMMON SNOW & ICE MANAGEMENT SYSTEMS UTILIZED WITH METAL ROOFING
Snow & Ice Retaining System: Mechanical
components (clamps, rails, bars, or individual snow stops/ guards, etc.) used on roofs in climates where moving or falling snow or ice could create a nuisance or hazard to people, equipment, or landscaping.

Heat Tape System: An electrically-heated cable or
wire used to melt snow and ice on a roof so that the snow and ice does not accumulate in critical areas. Electrically-heated cable or wire (aka “heat tape”) is often used to melt snow and ice in critical areas of a roof, such as valleys, gutters, and downspouts. Such systems must be designed and installed
to endure the forces of moving ice and snow and allow easy replacement since they can burn out or need repair. The self- regulating type of heat tape, which adjusts its heat output to the temperature encountered, is the most popular type.

THERE ARE THREE PRIMARY WAYS TO ATTACH SNOW & ICE RETAINING SYSTEMS TO A METAL ROOF
Seam Clamps: These allow attachment of the retaining
system to the roof panel’s standing seam without penetrating the metal roof panel. This attachment method is probably the most reliable way to attach a retaining system to a metal roof system. Careful attention must be paid when locating seam clamps to ensure that the standing seam metal roof system’s (including associated roof panel clips) ability to accommodate

thermal expansion and contraction are not compromised by the seam clamps. In most cases seam clamps should be located mid-way between one-piece roof panel clips and at the location of two-piece clips.

Adhesive: Snow guards are attached to flat areas of the roof panels using adhesives. The strength of this type of attachment depends on how well the adhesive adheres to the metal roof panels. With painted roof panels, proper
adhesion to the panel’s coating can be a concern, along with the adhesives impact on panel coating warranties. Under snow retention loads there may also be the risk of coating separation from the underlying substrate.

Fasteners: Some snow guards utilize fasteners to attach them to the panel’s flat areas or to the panel ribs. This approach is not normally recommended as it creates additional penetrations in the metal roof panels which can be points of possible water intrusion into the structure. These also have the potential to impede the thermal movement
of the roof panel by “fixing” it to the substrate. Exposed fasteners are always a concern of any warranted roof system and should be avoided if possible.

SUGGESTED RESPONSIBILITIES
The following are suggested responsibilities of the design professional, roof panel manufacturer, and snow retaining/ heat tape manufacturer to ensure the successful installation of these products:

Design Professional:
The overall design of the roof system and how it will function in varying climatic conditions (including the determination of what, if any, snow & ice retention or heat tape systems are used) is the responsibility of the design professional ( i.e. architect, engineer, roofing contractor, roof consultant, etc.).

The design professional should determine what, if any, snow & ice retention and/or heat tape systems are to be used on a project. The design professional should also consider how snow and ice will exit the roof.

The design professional should contact the snow & ice and/or heat tape system manufacturer for
recommendations of which system(s) are best suited for the project and what layout, spacing, attachment, etc. should be used to handle the anticipated snow and ice loads for the structure. As a minimum, the design snow loads required by building codes and local building authorities shall be used in this determination.

The type of roof material, the panel finish, and the roof panel’s configuration (e.g. minor ribs, embossed panels, etc.) may limit which type of snow-retaining system can be used.
Advise the roof panel manufacturer of any increased design loads due to the weight of the retained snow and ice.

AEP SPAN TECHNICAL BULLETIN #5
ADDRESSING SNOW & ICE

Include snow & ice retaining and/or heat tape system installation and layout requirements in the project documents (i.e. plans and specifications, addendums, etc.).

Roof Panel Manufacturer:
Provide a sample roof panel or a dimensioned drawing of the roof panel when requested by the design professional so that suitable attachment of the retaining system to the roof panel can be determined.

Though mechanically seamed panel samples are available, final seam configuration is not achievable without special tools. Dimensioned drawings of the installed roof panel configuration are typically used with these types of roof panels.

Advise the design professional how the method of attaching the snow or ice retaining system may affect the performance of the roof system. Snow & Ice Retaining or Heat Tape

Manufacturer:
Advise the design professional on which of their systems are best suited for the roof panel and climatic conditions of the project.

Recommend a layout of the snow & ice retaining and/ or heat tape system or supply the design professional
with sufficient information to allow them to determine an appropriate system layout.

Recommend procedures for attaching the snow & ice retaining or heat tape system to the roof panels.

Exposed copper or other metals that react negatively to steel should be avoided at all costs to prevent dissimilar metals from interacting.

IN SUMMARY
AEP Span’s position is neutral regarding the use of snow & ice retaining and/or heat tape systems. We recommend neither for, nor against, their usage. If such devices
are ultimately used, they must not impede the thermal movement (expansion & contraction) of the metal roof system, compromise its weather tightness, or be of a dissimilar metal to the roof materials.

Note that this bulletin is not intended to be a complete or exhaustive discussion of these specialty products or
systems but rather to present common aspects of their use with metal roofing. The designer or manufacturer of these specialty products or systems should be consulted for project specific recommendations and guidance.

AEP SPAN TECHNICAL BULLETIN #6
FALL RESTRAINTS AND METAL ROOFING

INTRODUCTION
AEP Span receives many inquiries regarding fall restraint systems (arresting devices) and their attachment to metal roofing. Metal roofing systems, and primarily standing seam systems provide a visible opportunity for attaching fall protection devices. Unfortunately, the loads that fall restraint devices are required to withstand are far beyond the capacity of our metal roof panels, clips, and fasteners. Simply put, AEP Span’s roof systems would fail under the extreme loads these devices require.

A review of the OSHA requirements governing fall restraint devices:

OSHA (FEDERAL REQUIREMENTS) 1926.760(d)(2)
“Fall arrest system components shall be used in fall restraint systems and shall conform to the criteria in § 1926.502 (see Appendix G). Either body belts or body harnesses shall be used in fall restraint systems.”

1926.502(d)(15)
“Anchorages used for attachment of personal fall arrest equipment shall be independent of any anchorage being used to support or suspend platforms and capable of supporting at least 5,000 pounds (22.2 kN) per employee attached, or shall be designed, installed, and used as follows: as part of a complete personal fall arrest system which maintains a safety factor of at least two; and under the supervision of a qualified person.”

ADDITIONAL REQUIREMENTS/STANDARDS ANSI Z359.18
Safety Requirements for Anchorage Connectors for Active Fall Protection Systems consensus standard; more stringent requirements than OSHA. Available through ANSI.org

ANSI Z359.1
(obsolete consensus standard)

While there are several fall restraint systems that attach directly to metal roofing seams, AEP Span is unaware of any systems that have included complete load path evaluation
– not just attachment of the fall restraint device to the panel seam, but also the loads imparted upon the panel & panel clip connection, the panel clip to clip fastener connection, and the panel fastener to substrate connection.

In addition, we are aware that most fall protection systems are evaluating OSHA loads for the downslope load direction (falls over eave), but loads perpendicular to the panel seams (falls over gable edge) also need to be accounted for. Loads in this direction induce complicated prying of panel systems that should also be evaluated.

IN SUMMARY
AEP Span’s roof systems are not designed to handle OSHA’s high fall protection load requirements. AEP Span recommends that fall restraint anchorages be attached directly to the main building structure, independent of the metal roof system.
Standard roof penetration flashing details are then incorporated to ensure a watertight connection.

Additional information regarding recommended fall restraint anchor types and associated flashing details is available upon request.

AEP SPAN TECHNICAL BULLETIN #7
ROOFING UNDERLAYMENTS

INTRODUCTION
Specifying underlayments for metal roofing often comes down to three basic needs. The first need for the installer and general contractor is to “dry the building in” so other work can proceed within the building. Second is for the owner and pursuer of a weathertightness warranty is to protect against the chance that moisture will penetrate the metal roof system and act as a secondary moisture barrier. Third is to allow a means of escape for ‘back side’ condensation which may occur in certain metal roof applications; this condensation must be directed out of the system. In all three cases the underlayment is intended to ultimately direct any moisture to the outside of the building envelope.

This technical bulletin will look at the different types of underlayments used with metal roofing. The discussion of underlayments within this document does not include internally driven vapor barriers; those used to block moisture originating from inside the building (ie. such as a natatorium). The main types of underlayment reviewed within this bulletin are: felts, rosin paper, polyethylene plastic, synthetic underlayments, and self-adhering membranes.

ASPHALT SATURATED FELT
The selection of this felt is often driven by the project specifications and cost. 30# asphalt saturated felt is perhaps the most widely used underlayment and most readily available. 30# felt installed and lapped horizontally with roofing nails and caps is adequate as a moisture barrier. Alternatively, two layers of 15# felt can be used but it does not lend itself to installation activity and wind conditions. Often one layer of 15# is installed and then shortly before the panel installation another layer is added. The down side of felt is that it may not be a durable, lasting underlayment for metal panel installation activities, it is not durable during windy conditions and has a relatively short life when exposed to the elements.

The use of asphalt saturated felt under metal roofing is perhaps the cheapest, most accessible, and most widely used. Unfortunately, even after a few short weeks of exposure, it will have less and less effectiveness as a water shedding material. Exposed and weathered felt eventually becomes a liability and must either be replaced or covered. The use of asphalt felt may work well if metal roofing can be installed within a few weeks. Asphalt roofing felts that have been over-exposed, dried out, curling, wrinkled, torn from wind damage, and/or patched may not provide the protection and performance that is needed.
Extremely weathered felt may actually retain moisture under the metal roofing and exacerbate water infiltration damages. Additionally, temperatures reached in certain conditions underneath the metal roof may cause the asphaltic material to become viscous and “run”, potentially leaving unsightly streak marks outside of the building envelope.”

ROSIN PAPER
Rosin paper is not considered a moisture barrier under metal roofing. The discussion of rosin paper within this bulletin is to clarify its use as a slip sheet. Slip sheets are traditionally used to prevent adhesion of asphalt felt to the back side of

metal roof panels. As the metal roofing expands and contracts during the daily thermal cycle the movement can displace, and even tear, the asphalt felt underlayments. Because aluminum and copper have much higher thermal expansion rates than steel the use of a rosin paper slip sheeting is more prevalent with these roofing materials. The use of a slip sheet under steel roofing is not a requirement for roofing warranties. There are questions as to whether rosin paper could actually retain any moisture that may infiltrate into the system rather than encouraging moisture to migrate out of the building envelope.

POLYETHYLENE PLASTIC
Polyethylene plastic is not a recommended underlayment for metal roofing. Even though polyethylene is an effect water barrier and is inexpensive, the material does not hold up well under prolonged expose to sun and heat. The long-term effects from radiant heat under metal panels is unknown with this product. Polyethylene does not perform well with fastener penetrations and has poor resistance to tears in the installation process. Plastic also does not provide adequate slip resistance on sloped surfaces and gets worse with the
presence of dust and moisture. The perm rate for this material is very high, to the point that it can possibly trap moisture at its’ surface.

SYNTHETIC UNDERLAYMENT
Synthetic underlayments are relatively new in the U.S. and have continued to evolve over the last ~20 years. A number of these polymer based synthetic underlayments have been used with considerable success. The initial aim
of synthetic underlayments was to replace asphalt saturated felt in the market. The success of these products has been overwhelming. The cost of synthetic underlayments is roughly double that of asphalt felt. That said, the list of advantages that synthetic has over asphalt felt is significant. Some of the key advantages:

Lighter Weight: Synthetics are roughly 1/5 the weight of asphalt felt. This allows for bigger rolls, and significantly more coverage per roll, resulting in lower installation costs.
Resistance to tearing – These underlayments have up to 10X the tear strength of asphalt felt. The tear resistance is very effective against winds as well as installation traffic and other construction activity.

Exposure or UV Resistance: Most synthetic brands list acceptable exposure times of up to six months. The much improved tear resistance and long-term exposure are perhaps the biggest advantages of synthetics.

Moisture Penetration: Appears to be very good for synthetic underlayments with data sheets indicating perm rates such as .05. Perm rates for asphalt felt in good condition are in the range of .02.

Some concerns exist regarding how well the synthetics manage fastener penetration. With 30# asphalt felts the theory is that the fastener head compression against the felt will cause the oil

AEP SPAN TECHNICAL BULLETIN #7
ROOFING UNDERLAYMENTS

in the felt to flush together creating an added level of moisture protection. With synthetic underlayments the protection is less clear; underlayment manufacturers strongly encourage the use of plastic capped underlayment fasteners to both reduce the opportunity for water intrusion, as well as improve the retention of the underlayment to substrate. Synthetic underlayments don’t have to be used across the entirety of the roof; they can be used in combination with self-adhering membranes in the lower slopes, valleys, eaves, etc. (the more risk prone areas) to provide a more complete, cost effective underlayment solution.

Future use of synthetic underlayments will only continue to expand and continued product improvements will occur as well. Note that exact compositions of synthetic underlayments are very proprietary and vary notably from one manufacture to another. Proper research should be done to select the most appropriate underlayment for the application. Synthetic underlayments are allowed for AEP Span Weathertightness Warranty purposes if specified and approved for use under metal roofing by the underlayment manufacturer.

SELF-ADHERING MEMBRANE
Self-adhering membranes are considered the foremost underlayment for metal roofing. The key attributes of these products provide for the best protection. Some of these attributes are:

Self Healing: Holes created by fasteners installed through membrane underlayments tend to seal around the fasteners, reducing the possibility of moisture penetration.

Preparation: Each of these products have specific requirements at installation such as surface priming of substrates. Thorough cleaning of substrates and removal of protrusions, decking voids, etc. may be required to improve adhesion and reduce opportunity for underlayment damage.

Exposure Time: Ranges from 30 to 90 days. Longer exposure times may produce uneven underlayment surfaces.

Temperature Resistance: Self-adhering, high-temperature underlayments are designed specifically for use under metal roofing systems in order to protect against the high temperatures that are possible under metal roofing systems.

Variations: Some versions of this product are only made for composition shingles and may not have enough temperature ratings or flow temperature to be suited for metal roof applications.

Targeted Usage: Self adhering membranes are often used in combination with felts or synthetics such that eaves, valleys and perhaps hips and ridges are stripped with several feet of membrane and the balance of the roof with the less expensive product.

Compatibility: Some self-adhering underlayment manufacturers caution against physical contact with EPDM,

creosote, wood pitch (resin), gasoline/oil/diesel fuels, flexible PVC and numerous solvents. Adhesion can also be an issue for some substrates such as polystyrene (Styrofoam).

As with any underlayment usage, consult all product usage and installation requirements with the manufacturer and also ensure the product’s compatibility with metal roofing.

The only requirement for AEP Span warranty purposes is that the membrane not have a granular surface. There is a great concern that the granular surface may scratch and damage the wash coat and metallic coating on the underside of the metal panels allowing any moisture to deteriorate the panel integrity.

FIRE RATED UNDERLAYMENTS
A number of the underlayments on the market have obtained fire resistance ratings. Use of these underlayments as a component of a fire rated UL790 assembly is generally allowed. Consult the UL website for AEP Span fire listings and acceptable underlayment types. As of the writing of this bulletin, only one synthetic underlayment is available in the
market that can boost most of AEP Span’s metal roofing panels to a Class A fire rated assembly over combustible decking.
The product is GAF Versashield. Consult the AEP Span UL listings for approved underlayments and constructions for Class A rated assemblies. [UL Link]

RADIANT BARRIERS
In recent years, radiant barriers with very low perm rates are also being utilized under metal roofing. These radiant barriers not only act as vapor barriers but also provide resistance to heat transfer into or out of the building envelope.

IN SUMMARY
There are a few primary types of roofing underlayments used with metal roofing – asphalt saturated felt, rosin paper (slip sheeting), synthetic underlayments, and self-adhering membranes. There is also a large number of variations/ formulations to these as well, especially with the synthetics.
This bulletin provides some general guidance however
it is ultimately the responsibility of the specifier or design professional to select the proper underlayment based on each project’s physical and environmental requirements.

AEP SPAN TECHNICAL BULLETIN #8
LIGHTNING PROTECTION SYSTEMS

INTRODUCTION
A lightning protection system provides a direct, continuous electrical path from the building rooftop down to earth. These systems are installed to reduce the risk to electrically and thermally sensitive building materials from lightning strikes. When these systems are properly designed and installed, the lightning’s electrical discharge will follow a safe, conductive path to the ground.

Metal roofing also acts as an electrical conductor, dissipating the electrical charge across the roof surface during a lightning strike. Metal roofing is also a noncombustible material. Both of these benefits are significant and make metal a very desirable roofing material. That said, metal roofing is not a complete lightning protection system, so a properly designed and installed system is important in lightning prone areas.

INSTALLATION CONSIDERATIONS
Dissimilar Metals
Regarding the installation of lightning protection systems, one of AEP Span’s primary recommendations is to always avoid the use of dissimilar metals. Galvanic corrosion will occur when two dissimilar metals come into contact with each other, especially in the presence of moisture. AEP Span’s Zincalume® (aluminum-zinc) coated steel panels should
not be in contact with, or be exposed to runoff from, roofing accessories (including lightning protection systems) that utilize copper, brass, graphite, and/or lead. AEP Span recommends that aluminum components be used for lightning protection systems. Aluminum does not significantly react when in contact with Zincalume® coated steel roof panels.

Contact AEP Span if there are further questions or concerns regarding the topic of dissimilar metals.

Attachment
AEP Span recommends that standing seam clamps (S-5!® clamps or similar) be utilized for the attachment of lightning protection systems. The use of seam clamps helps reduce unnecessary roof penetrations by allowing the attachment of lightning protection systems directly to the roof panel standing seams. In some applications there may not be a location
for a seam clamp to be utilized (i.e. along gable edges or with corrugated panels). In these cases it may be desirable to utilize mounting pads that are adhesively attached to the panel surface.

It is important that mounting pads utilize an appropriate adhesive that will bond to Zincalume® or Kynar® coated steel panels. Using an adhesive that does not bond well to these surfaces, or that negatively reacts to these surfaces, can impact the overall performance of the lightning protection system and the metal roof system.

Note: AEP Span’s limited warranties do not cover seam damage, paint scratches, paint or coating issues from adhesives, or other damage that occurs from installation or use of lightning protection systems and their components.

AEP SPAN TECHNICAL BULLETIN #9
PREVENTING STORAGE CORROSION

INTRODUCTION
Pre-painted and galvanized building panels and components have been successfully used for many years. In general, properly installed building materials under normal service conditions have excellent corrosion resistance. However, pre- painted and bare building materials are subject to premature corrosion failures prior to installation, if they are not handled and stored properly. Excessive storage periods or poor storage conditions often result in water intrusion. Prolonged exposure to wet conditions can cause paint blistering and galvanized substrate corrosion or staining in as little as 2 weeks.

ENVIRONMENTAL AND SERVICE CONDITIONS
Water is a necessary prerequisite for corrosion of stored panels or components. When water or water vapor is available along the sides of a panel bundle or a column/purlin stack, it may penetrate between the panels or parts by capillary action. If proper precautions are not taken during transport, water may be present upon delivery at the job site. Material must be inspected at the time of delivery. Ambient humidity and temperature cycles will also promote water intrusion into stored bundles and stacks through condensation. Finally, rain and snow are other potential sources of water that can cause storage corrosion and staining.
Besides water, two other important factors that contribute to the corrosion are temperature and exposure time. Corrosion will accelerate with increased temperature. Given enough time, panel bundles, columns and/or purlins will eventually become wet and storage corrosion and staining may occur. Storage corrosion can be prevented by:

Reducing site storage time.
Decreasing water contact.
Moderating temperature extremes.
STORAGE
Prolonged storage will always increase the likelihood of storage corrosion; therefore, the best prevention is to minimize the storage time. Proper storage limits the collection of water
from rain, snow and condensation on the panel surfaces. Under roof storage is always preferred. If panel bundles or other components have to be stored outdoors, a number of

precautions must be taken to prevent storage corrosion. Material should be stored in a level area out of the way of other activities to minimize the number of movements required. If the material is stored on the ground, i.e. dirt, grass or gravel, a plastic ground cover must be put down to minimize condensation of water from the ground onto the panels or components. The material must then be raised off the plastic ground cover to avoid contact with water puddles, and allow for air circulation to promote drying of condensed water. The material must be stored on an angle, or slope, to promote drainage of water.

with the material. Sufficient support must be provided to the raised and angled material to avoid excessive bowing, which may result in low spots that could hold water.

Example of proper storage:

REMEDIES
Storage corrosion on pre-painted material cannot be remedied. Once the corrosion process has begun the film integrity of the paint is compromised. Panels displaying any type of corrosion or paint bubbling should not be installed. Light corrosion or staining (white or black in color) on bare galvanized material may be cleanable; contact your AEP Span representative for proper cleaning techniques.

References:
National Coil Coating Association, Tool Kit #1 “Preventing Job Site Storage Corrosion of PrePainted Building Materials”
GalvInfo Center, GalvInfoNote 3.2 “Protecting Galvanized Steel Sheet Products from Storage Stain”

AEP SPAN TECHNICAL BULLETIN #10
TOUCH-UP PAINT

Scratches and very minor damage may occur during handling and installation of painted roofing and wall panels. In these instances, it may be desirable to use touch-up paint to repair the blemishes. Keep in mind, touch-up paints are quick fixes and when used properly, will result in a satisfactory appearance. Misuse or over-use can result in spoiling the overall appearance.

The paint systems used on factory painted steel have a built-in color and gloss retention that is only achieved
through the oven-baked process. Air-dried paints will fade and chalk much faster than the oven-baked. These different weathering characteristics must be taken into consideration when touch-up work is contemplated. Nothing looks worse than the blotchy appearance of excessive touch-up painting. Superficial scratches which are not too obvious from a distance of 6-9 feet will likely be obscured by normal soiling and weathering. If you decide to use touch-up paint, use it sparingly and only to cover up those areas where paint has been removed. A paint pen or 1/4" artist brush should be used for these repairs.

Edges of deep scratches should be lightly sanded or “feathered” with #400 grit sandpaper. If a scratch extends through the paint and the protective metal layer exposing raw steel, it should be treated with a zinc-rich or similar primer before touch-up application. If feathering and/or priming are not necessary, areas to be touched-up should at least be wiped with mineral spirits to remove dirt, wax or other contaminants before colored touch-up is applied.

The recommended paint type for touch-ups is an acrylic silicone paint. This paint type can be found at local paint stores or anAir Dried Kynar system (ADS II), can be sourced through PPG Industries at the following link.

http://corporate.ppg.com/Media/Newsroom/2016/PPG- announces-licensing-agreement-for-KYNAR-ADS-II 

Special attention should be given to the manufacturer’s instructions; including direct skin or eye contact, ventilation and potential flammability. Aerosol or spray applications are not recommended for blemish or scratch repairs. The best tool for this type of repair is a paint pen or good quality, 1/4-in. artist brush. Only the narrow edge of the paintbrush should actually contact the scratch or blemish.

AEP SPAN TECHNICAL BULLETIN #11
ROOF SYSTEM CARE AND MAINTENANCE

Our high quality roof systems are designed to be installed to offer uncompromising value and ease of maintenance throughout the life of the roof. Your roof system should be
inspected annually to ensure flashings, roof panels, and roof conditions are still in good working order.

The following operating and maintenance instruction will ensure that your roof system performs for years to come.

CLEAR ROOF PANELS AND GUTTERS FROM DEBRIS ACCUMULATION
The build-up of foliage and dirt can block runoff and clog gutters and downspouts. Ensure the roof system and gutters are cleared of any accumulating debris.

CHECK EXPOSED FASTENERS (If applicable)
Though your roof is designed for concealed fastener attachments, some flashing and roof penetration conditions may utilize exposed fasteners. Those fasteners include self-sealing gasket head fasteners and pop rivets. Check the condition of the fasteners to ensure the self-sealing gaskets are in good working order and have not been over driven or deteriorated. Rivets and fasteners should be secured tightly to the roof panels or flashing and should not be loose or backed out.

CHECK CONDITION OF EXPOSED SEALANTS
(If applicable)
Just like fasteners, our roof systems are design to be used with little to no exposed sealant. Exposed sealant may have been used to seal roof penetrations and select flashing conditions. If there is any exposed sealants on your roof system, check that the sealant is in good working order. Deterioration, cracks, or pinholes in the sealant are a red flag that the sealant may have reached the end of its lifecycle and should be replaced.

CHECK FOR STANDING OR PONDING WATER
(low slope applications)
Standing or ponding water can be detrimental to the coating of the roof system if left for an extended period of time.

MINIMIZE FOOT TRAFFIC
The paint systems are not design to handle a heavy volume of foot traffic and should be minimized to prevent damage. Periodic inspections and maintenance are encouraged.
However, if the roof system is intended for heavy foot traffic, roof mounted walkways should be utilized.

The factory-applied finish used on pre-painted steel is extremely durable and will last many years longer than ordinary conventional field applied paint. However, it may be desirable for cosmetic purposes to clean the finish occasionally to ensure the longevity of the paint and roof system.

Dirt pickup may cause discoloration on the finish when it has been exposed to dirt-laden atmospheres for long periods
of time. Additionally, slight chalking will ultimately cause

some change in appearance in areas exposed to sunlight. A thorough cleaning will often restore the appearance of the panels and render repainting unnecessary. An occasional
subsequent light cleaning will help maintain good appearance.

RUST SPOTTING (Steel)
During installation, improper techniques in cutting and drilling of pre-painted steel can cause rust spotting. Hot chips from drilling or self-tapping screws, or chips from metal saws or cutting discs may embed themselves in the paint finish. These chips can then rust and form unsightly red spots in the coating, giving the visual impression that the substrate may be rusting. It is imperative to brush off any chips which are stuck to the painted surface. A stiff bristle nylon brush is recommended.

CLEANING
In some cases, simply washing with plain water, using a hose or pressure spray, would be adequate. For areas where
dirt collection is heavier or more persistent, a solution of water and detergent (1/3 cups of Tide® per gallon of water, for example) may be used. A clear water rinse should follow immediately. If Product is installed in a mild marine
environment, less than 1 mile and greater than 1000 feet from breaking surf, Product should be washed two times per year.

Mildew may occur in areas subject to high humidity. Mildew spores can grow in dirt deposits, even on factory baked finishes. To remove mildew along with the dirt, the following solution is recommended:

1/3 cup detergent (Tide® for example)
2/3 cup Sodium Phosphate (Soilex for example)
1 quart 5% Sodium Hypochlorite solution (Clorox for example)
3 quarts of water

Strong solvent and abrasive type cleaners should be avoided, as they may damage the finish. Caulking compounds, oil, grease, tars, etc., can be removed by mineral spirits applied only to those areas which are contaminated. Always follow the use of the mineral spirits with detergent cleaning and clear rinsing.

AEP SPAN TECHNICAL BULLETIN #12
WALL SYSTEM CARE AND MAINTENANCE

Our wall systems are designed to be installed for years of uncompromising value and ease of maintenance throughout the life of the wall system. Your wall system should be inspected annually to ensure flashings, wall panels and wall conditions are still in good working order.

The following operating and maintenance instruction will ensure that your chosen wall system performs for years to come.

CLEAR WALL PANELS FROM DEBRIS ACCUMULATION
Keep dirt, irrigation, drainage, vegetation and weed whips away from all wall panels. Do not allow direct contact. Failure to do so can lead to early deterioration.

CHECK EXPOSED FASTENERS (If applicable)
ASC Building Products manufactures wall panels with both concealed and exposed attachment. Select panels, flashing and wall penetration conditions may utilize exposed fasteners. Those fasteners include self-sealing gasket head fasteners and pop rivets. Check the condition of the fasteners to ensure the self-sealing gaskets are in good working order and have not been over driven or deteriorated. Rivets and fasteners should be secured tightly to the wall panels or flashing and should not be loose or backed out.

CHECK CONDITION OF EXPOSED SEALANTS
(If applicable)
Our wall systems are design to be used with minimal exposed sealant. Exposed sealant may have been used to seal wall penetrations, windows, doors and select flashing conditions. If there is any exposed sealants on your wall system, check that the sealant is in good working order. Deterioration, cracks or pinholes in the sealant are a red flag that the sealant may have reached the end of its lifecycle and should be replaced.

CHECK FOR STANDING OR PONDING WATER ALONG THE BASE OF A WALL CONDITION
Standing or ponding water can be detrimental to the coating of the wall system if left for an extended period of time.

MINIMIZE EXPOSURE
Prolonged contact with vegetation, dirt or gravel, sustained exposure to animals or animal waste, or where the product is in contact with, or subject to runoff from lead, copper, CCA, ACQ,
CA, pressure treated, green or wet lumber, or wet insulation or other treated lumber (outdoor wood) or fire retardant impregnated or treated wood shakes can all be detrimental to the steel and factory coating.

The factory-applied finish used on pre-painted steel is extremely durable and will last many years longer than ordinary conventional field applied paint. However, it may be desirable for cosmetic purposes to clean the finish occasionally to ensure the longevity of the paint and wall system.

Dirt pickup may cause discoloration on the finish when it has been exposed in dirt-laden atmospheres for long periods
of time. Additionally, slight chalking will ultimately cause some change in appearance in areas exposed to sunlight. A thorough cleaning will often restore the appearance of the panels and render repainting unnecessary. An occasional
subsequent light cleaning will help maintain good appearance.

RUST SPOTTING (Steel)
During installation, improper techniques in cutting and drilling of pre-painted steel can cause rust spotting. Hot chips from drilling or self-tapping screws, or chips from metal saws or cutting discs may embed themselves in the paint finish. These chips can then rust and form unsightly red spots in the coating, giving the visual impression that the substrate may be rusting. It is imperative to brush off any chips which are stuck to the painted surface. A stiff bristle nylon brush is recommended.

CLEANING
In some cases, simply washing with plain water, using hoses or pressure sprays, will be adequate. For areas where dirt collection is heavier or more persistent, a solution of water and a detergent (1/3 cups of Tide per gallon of water, for example) may be used. A clear water rinse should follow immediately.
If Product is installed in a mild marine environment, less than 1 mile and greater than 1000 feet from breaking surf, Product should be washed two times per year.

Mildew may occur in areas subject to high humidity, and mildew spores can grow in dirt deposits, even on factory baked finishes. To remove mildew along with the dirt, the following solution is recommended:

1/3 cup detergent (Tide® for example)
2/3 cup Sodium Phosphate (Soilex for example)
1 quart 5% Sodium Hypochlorite solution (Clorox for example)
3 quarts of water

Strong solvent, abrasive type cleaners and pressure washers should be avoided, as they may damage the finish. Caulking compounds, oil, grease, tars, etc., can be removed by mineral spirits applied only to those areas which are contaminated.
Always follow the use of the mineral spirits with detergent cleaning and clear rinsing.

AEP SPAN TECHNICAL BULLETIN #13
CLEANING COIL COATINGS

Coil Coatings present a relatively non-adherent, inert surface to airborne soil. If needed, a variety of methods for removal of surface deposits is available. However, note these precautions:
Do not use wire brushes, steel wool, sandpaper, abrasives or other similar cleaning tools which will mechanically abrade
the coating surface. Some of the cleaning agents listed below should be tested in an inconspicuous area before use on a large scale. Always test a small area first.

HOT OR COLD DETERGENT SOLUTIONS
A 5% solution in water of commonly used commercial and industrial detergents will not have any deleterious effect on a Coil surface. These solutions should be followed by an adequate rinse of water. Use cloth, sponges or a soft bristle
brush for application. Cleaning should be done on the shaded side of the building or, ideally, on a mild, cloudy day.

SOLVENTS
Most organic solvents are flammable and/or toxic, and must be handled accordingly. Keep away from open flames, sparks and electric motors. Use adequate ventilation, protective clothing and goggles. Remove non-water soluble deposits (tar, grease, oil paint, graffiti, etc.) from Coil surfaces using these solvents with caution:

Alcohols
Denatured alcohol (ethanol)
Isopropyl (rubbing) alcohol
Methanol (wood alcohol)

Petroleum Solvents
VM&P naphtha
Mineral spirits
Turpentine (wood or gum spirits)
Aromatic Solvents
Xylol (xylene)
Toluol (toluene)
These solvents should be used with caution on a Coil surfaces. Limit contact to five minutes. Test a small area first.

Ketones, Esters, Lacquer Thinner
Methyl ethyl ketone (MEK)
Methyl isobutyl ketone (MIBK)
Ethyl acetate (nail polish remover)
Lacquer thinner
These solvents should be used with great caution on a Coil surface. Limit contact to one minute. Test a small area first. Panel manufacturer and coating supplier are not responsible for damage from unrestricted use of these.

Acetone/Paint Remover
Do not use acetone or paint remover on Coil surfaces.

CHEMICAL SOLUTIONS
Sodium hypochlorite solution (laundry bleach, Clorox)
Hydrochloric acid (muriatic acid)
Oxalic acid
Acetic acid (vinegar)
Hydrochloric acid (10% muriatic acid), diluted with ten volumes of water, may assist in removing rust or alkali mortar stains from Coil surfaces. Limit contact to five minutes. Caution: Acid solutions are corrosive and toxic. Flush all surfaces with water after use. Oxalic acid solutions or acetic acid (vinegar) may be used for the same purpose. Flush with water after use. Laundry bleach may assist in removing certain stains.

CLEANING
In some cases, simply washing with plain water, using a hose or pressure spray, would be adequate. For areas where dirt collection is heavier or more persistent, a solution of water and detergent (1/3 cups of Tide® per gallon of water, for example) may be used. A clear water rinse should follow immediately.
If Product is installed in a mild marine environment, less than 1 mile and greater than 1000 feet from breaking surf, Product should be washed two times per year.

Mildew may occur in areas subject to high humidity. Mildew spores can grow in dirt deposits, even on factory baked finishes. To remove mildew along with the dirt, the following solution is recommended:

1/3 cup detergent (Tide® for example)
2/3 cup Sodium Phosphate (Soilex for example)
1 quart 5% Sodium Hypochlorite solution (Clorox for example)
3 quarts of water

EXCESS SEALANT REMOVAL
Precautions should be taken to prevent sealants from getting on the painted surface. Sealants may be very difficult to remove. If any does get on a Coil surface, it should be removed promptly with a solvent such as alcohol or a naphtha type.
Caution: It may be possible for solvents to extract materials from sealants which could stain the painted surface or could prove harmful to sealants; therefore, these possible effects must be considered. Test a small area first.

AEP SPAN TECHNICAL BULLETIN #14
REMOVAL OF STUBBORN STAINS, SEALANTS, & PEEL COAT

This bulletin defines what chemicals are acceptable for cleaning stubborn stains, sealant, or strippable film from the surface of AEP Span roof or wall panels.

STUBBORN STAINS OR SEALANT
AEP Span recognizes the following chemical solutions to be used to removed stains while not adversely affecting the paint coatings:
Prep® Prep™400* https://www.ppgpaints.com/products/ duraprep-prep400-overspray-remover
Denatured Alcohol
Mineral Spirits
Naptha (Not available in California)
WD-40®
Goo Gone
Note: A small panel area should be initially selected to determine what the best course of action should be before

larger panel areas are subjected to cleaning using these methods.
PEEL COAT (STRIPPABLE FILM)
Prolonged exposure to UV, heat or cold may make removal of the factory applied peel coat difficult.

AEP Span stresses the importance of removing peel coat as soon as possible after receiving products to ensure easy film removal. Prolonged UV exposure, wet conditions or long- term panel storage with film applied will likely make removal very difficult.

For detailed guidelines on removing peel coat or left-over residue see Technical Bulletin #15 Peel Coat Guidelines and Best Practices.

AEP SPAN TECHNICAL BULLETIN #15
PEEL COAT GUIDELINES AND BEST PRACTICES

This bulletin details proper jobsite storage, removal and clean-up of panels and flashings supplied with protective peel coat film.

JOBSITE STORAGE
Stored panels and flashings should be protected from exposure to moisture, sunlight and precipitation. It is recommended to store panels and flashings indoors for the utmost protection.
If outdoor storage is the only means, it is recommended to store panels and flashings elevated under a water-proof tarp and tilted in such a way to not entrap moisture and facilitate drainage. Exposure to UV light and weather elements can result in excessive adhesion to the surface. The ﬁlm can also degrade to the point it can no longer be peeled oﬀ.

Material with peel coat applied should not be stored for longer than 30 (thirty) days.

REMOVAL OF PEEL COAT
Protective ﬁlms should be removed gradually beginning at one end peeling back at a 180°degree angle with a smooth even motion. Do not quickly jerk the protective ﬁlm. Inspect for any adhesive residue once the peel coat is removed. If residue remains on the surface, follow the below cleaning guidelines.

DO NOT remove peel coat in freezing conditions. The recommended temperature range for film removal is between 40°F (16°C) and 90°F(32°C).

DO NOT remove

As a general rule the peel coat will be resistant to the absorption of the Goo Gone Pro-Cleaner, Citrus-based cleaner and DuraPrep Prep 400 cleaners.

Remove a much of the film or residue as possible.

Panels and flashings must be completely dry before applying cleaners. With the dry substrate out of direct sunlight, saturate the film backing with the selected cleaner. Keep the film saturated with repeated applications until the film swells and softens. The remover needs to wick under the edges of the film which can be aided by gently agitating the film edge with soft bristle brush.

Once the film has softened, lift and remove with fingernail or by
means of scraping with a soft, non- abrasive scraper, being careful
not to scratch or damage the
panel surface. It is common for only the area of film near the edge to be removed;
it may take
repeated cycles to Example of leftover adhesive residue on panel leg.
remove all the film
or residue. For left-over residue, saturating then wiping with a soft cloth may be sufficient.

peel coat if panels are wet. Panels and

Example of peel coat removed in freezing conditions.

When peel coat or residue is completely removed, a general-purpose surface cleaner may be used with a soft

flashings should be moved indoors and allowed to dry before removing the protective film.

Using sunlight to warm or dry the panels and flashings could result in UV degradation of the peel coat. Heat lamps or dryers can be used to warm up or dry off panels.

Peel coat should be removed from installed panels and flashings within 24 (twenty-four) hours.

REMOVAL OF STUBBORN PEEL COAT AND RESIDUE
There are several options available that may aid in removing stubborn peel coat and/or left-over residue.

Citrus-based hand cleaners (non-abrasive)
Goo Gone Pro-Power Adhesive Remover
PPG DuraPrep® Prep 400 Overspray & Graffiti Remover (For use on Dura Tech™ 5000 paint systems only)
Water applied with portable steam cleaner

cloth to remove any light haze or residue that remains. Please reference Technical Bulletin #13 Cleaning Coil Coatings for approved painted surface cleaners.

A portable steam cleaner can also be used to swell and soften the film for easier removal.

Cleaners should always be tested on a small area first. Carefully read and follow the manufacture’s precautions and directions. The information provided in this technical bulletin is for general knowledge only; it is not to be considered an exact method for removal of peel coat or adhesive residue.

Care should be taken to avoid cleaners from contacting siding, windows, doors and vegetation.

Follow all local environmental guidelines for proper disposal of cleaning agents.

AEP SPAN TECHNICAL BULLETIN #16
REFLECTANCE

The coatings world uses a lot of terminology that can become a bit confusing. “Reflectance” is a perfect example of a word that is used to describe two very different properties.

LIGHT REFLECTANCE VALUE
Light Reflectance Value, or LRV, measures the amount of visible or usable light that reflects from a surface. LRV is expressed as a percentage from 0 to 100; the higher the number the more visible light that is reflected. Typically, lighter colors will have a higher value than dark colors, but texture can impact LRV as well. Rough textures tend to reflect less visible light.  Gloss and sheen are two other terms used to describe visible reflection of a surface. Gloss is the measurement of visible light at a 60° angle from the surface, while sheen is measured at 85°. High gloss/sheen results in high glare or shine from a surface, while low gloss/ sheen surfaces have a flat or matte appearance. Glare, often a concern with pre-painted roofs, is controlled by lowering the sheen value.

SOLAR REFLECTANCE VALUE
Solar Reflectance Value, or SRV, measures the amount of total solar radiation, visible, infrared and ultraviolet, that
is reflected from a surface (Total Solar Reflectance, TSR, is used as well). SRV is expressed as a percentage from 1 to 100; the higher the number the more solar radiation that is reflected. As with LRV, light colored objects often have a high SRV while dark colors are low. However, with the advent of “cool” pigments, it is possible for a medium to dark color to have a high SRV. The higher the SRV value the cooler the surface stays in direct sunlight. Gloss and sheen values have no impact on SRV. Note: Solar Reflectance Index, or SRI, is calculated from the SRV and emittance value of a material, therefore it is also different and independent from LRV.

Light Reflectance Value ≠ Solar Reflectance Value ≠ Solar
Reflectance Index

LRV and SRV and SRI are NOT the same property and cannot be used interchangeably!
While there is some overlap between LRV and SRV, and many coated surfaces may have similar LRV and SRV values, they are not the same measurement. The examples below demonstrate the differences; while LRV may be similar for colors that are visually the same, the SRV can be vastly different.

COLOR	SRV	LRV	SRI	60° Gloss	85° Sheen	
FOREST GREEN 1	30	9	29	10	13	
FOREST GREEN 2	17	15	12	13	28	
						
DARK BRONZE 1	32	8	32	11	13	
DARK BRONZE 2	6	7	3	7	11	
						
PARCHMENT 1	51	40	58	11	12	
PARCHMENT 2	50	51	56	11	20	
						
BLACK 1	30	5	29	21	25	
BLACK 2	6	6	3	19	26	

AEP SPAN TECHNICAL BULLETIN #17
DISSIMILAR METALS

INTRODUCTION
AEP Span’s steel-based products, painted and bare, feature a metallic-coating that provides long-lasting resistance from corrosion. This coating is applied during the steel production process prior to the application of paint. Metallic-coatings consist of either zinc (sold as TruZinc® or galvanized) or a specialty mix of aluminum and zinc (sold as ZINCALUME®). Care must be taken during the design and installation phase of metallic-coated products to avoid the unintentional creation of galvanic corrosion. This rapid form of corrosion is induced
when metals of varying types (dissimilar metals) are installed in direct contact with one another in a corrosive environment.
GALVANIC CORROSION
Galvanic or bi-metallic corrosion is a reaction in which one metal will sacrifice itself (or dissolve) to protect the different, less active metal, leading to visible corrosion. Galvanic corrosion occurs between dissimilar metals in certain corrosive environments and typically requires three criteria in which to occur:
Two or more dissimilar metals,
Metal to metal contact, and
Both metals to reside in the same conducting solution/
corrosive environment, i.e. salt air or water.
Metals can be viewed as active or noble based on their position on the galvanic scale, simplified in Table 1 below. The further apart these metals are on this scale, the greater the potential for a reaction between the metals. In addition to the dissimilarity of the metals, the severity of the environment will influence the potential for galvanic corrosion. Common factors influencing environmental severity can include direct proximity to salt water or chemical spray, the frequency of breaking surf (which generates airborne salt-laden particulates), and how frequently the surface is rinsed by rainfall.

More Active Metals (Anode)
Zinc
ZINCALUME Steel
Aluminum Steel Lead Copper
Stainless Steel
Less Active or Noble Metals (Cathode)

Table 1: Galvanic Series of Metallic Activity

.

IN APPLICATION
Installations featuring galvanic corrosion are commonly attributed to improper fastener and accessory selection. This includes the use of stainless steel and copper products in direct contact with metallic-coated metal roofing and siding profiles.
Stainless-Steel Hardware (Clips, Fasteners, etc) Galvanic corrosion can be caused by stainless-steel fasteners, rivets, light fixtures, window frames and other accessories recessed in metallic-coated panels in corrosive environments.

Initially this may appear as the apparent bubbling of the painted metal roof or siding surface around the stainless-steel fixture. Often falsely identified as a paint failure, this bubbling is the steel underneath corroding, resulting in the loss of paint adhesion.
AEP Span’s stainless-steel hardware offering, such as clips and fasteners, are not intended to be used with ZINCALUME coated steel profiles in corrosive environments. In these environments stainless steel components should be used in conjunction with profiles fabricated out of aluminum.
Copper and Copper Treated Lumber
Metallic coated steel will experience accelerated corrosion when it is in contact with copper, this includes copper treated lumber. Leeching of copper from treated materials, such as through water run-off from rainfall or condensation, can result in corrosion without direct metal to metal contact. In these instances, the protective oxide film which naturally forms on aluminum-zinc coatings is broken down by copper in localized areas. Pitting corrosion ensues which is a highly accelerated form of attack. Zinc coatings are not generally subject to pitting but will demonstrate the effects of galvanic corrosion when installed in direct contact with copper.
AEP Span recommends avoiding the use of copper where galvanic corrosion may be a concern. If the use of copper cannot be avoided, AEP Span recommends that insulated copper or a protective coating over the copper be used
to prevent exposure. Any electrical terminals that utilize exposed copper should also be sealed with shrink tape or similar method This includes but is not limited to grounding wire for Photo Voltaic Arrays, Lightning Protection, and Pipe Penetrations.
Galvanized Steel and ZINCALUME Coated Steel Unpainted galvanized steel must not be used for roofing or rainwater goods (including valleys and gutters) to collect water runoff from ZINCALUME Steel or other more noble metals.
ZINCALUME Steel and painted ZINCALUME Steel can be used to collect water from galvanized catchment material. Irrespective of galvanic corrosion considerations, ZINCALUME Steel panels & gutters will typically give a longer service life than traditional galvanized steel. Neither product should be used as catchment material for roofs featuring more noble metals such as aluminum or copper.
WARRANTY IMPLICATIONS AND REMEDY
Product deterioration or corrosion created by the improper installation of dissimilar metals will void any warranty supplied by AEP Span. This includes product performance, paint system, and corrosion warranties.
If galvanic corrosion is identified, this issue must be rectified as promptly as possible due to the rapid rate at which it
can spread. Remedies may include the replacement of the panels impacted by corrosion and the substitution or relocation of the associated dissimilar metals. For more information on the identification or rectification of galvanic corrosion, please contact AEP Span.

AEP SPAN TECHNICAL BULLETIN #18
Zinc in the Rainwater Runoff from ZINCALUME® Roofs

RE: Zinc in the Rainwater Runoff from ZINCALUME® Roofs To Whom It May Concern:
ZINCALUME® (Galvalume®) sheet features an alloy coating on the steel that is approximately 55% aluminum and 45% zinc. This coating has been well documented to provide outstanding corrosion resistance and long service life – at least two to four times that of pure-zinc coated roofs (galvanized). Long service life and low corrosion rates mean little zinc is being dissolved from the sheet.

AEP Span is committed to protecting the environment and to providing accurate information and product support to our customers. As an active member of several steel industry trade associations, we are supporting the on-going investigations to identify those factors which
influence the amount of zinc present in the rainwater runoff from a ZINCALUME roof. We believe that these factors include but may not be limited to:

How much acid is present in the rainfall;
The intensity of the rainfall, i.e., how many inches per hour it is raining;
The duration of the rainfall, i.e., how long does the rainfall last;
The total area of the roof;
The temperature of the roof surface.

Predicting the absolute concentration of zinc present in roof runoff for any rainfall situation is nearly impossible, due to the combination of factors above.

We do believe that the amount of acid present in the rainfall is the most important factor. The pH of the rainfall is a measure of how much acid is present. The lower the pH is, the more acidic the rainfall is. Water that has no acid present would have a pH of 7.0. Normal rainfall would have a pH of about 5.4 to 5.6. The reason that normal rainfall has a pH lower than 7.0 is that carbon dioxide is absorbed into the rainfall from the atmosphere. The carbon dioxide produces carbonic acid, a very weak acid. At pH levels from 5.6 down to about 5.0, extremely small quantities of zinc would be present in the rainwater runoff from a ZINCALUME roof.

In the United States, the pH of rainfall west of the Mississippi is most often above pH 5.0. The rainwater runoff from ZINCALUME roofing in those localities is unlikely to contain more than very small trace quantities of zinc, quantities so small they would be barely detectable even using the most sophisticated techniques. As rainfall moves east across the Mississippi, it picks up acid that has been discharged to the atmosphere, primarily by coal fired electric generating plants. The highest concentration of acid in rainfall (the lowest pH) is usually found along the northeast coast of the United States. For the reasons stated at the outset, predicting the quantities of zinc that would be present during rainfalls in this region is difficult and complex. To generate a number and say that this is “the number” is virtually impossible.

Although the acid rain areas could be expected to produce a higher zinc runoff rate than the west- ern, non-acid rain areas, we believe the zinc concentration in acid rain runoff will still be exceed- ingly small. One measure of this is the outstanding long-term performance of the ZINCALUME roofs. We have inspected ZINCALUME roofs 20 – 25 years old that are located in acid rain areas. They are without exception in excellent condition and have many years of life ahead of them. This simply would not be the case if the zinc were corroding or dissolving significantly. We nonetheless are supporting studies underway to better understand and characterize the factors that would affect the rainwater runoff from ZINCALUME roofs.

These steel industry associations are investigating methods to remove even trace amounts of zinc from the rainwater runoff. Wetlands are an excellent method for removing zinc. Wetlands change the zinc from a form that is easily dissolved in water to one that is not at all soluble in water, even acidic water. The small quantities of zinc that may be present in the runoff from ZINCALUME roofs are then locked up in the soil and not available for uptake by plants or animals. Other tests are being conducted to determine if non-wetland soil conditions, e.g., topsoil covered with lawn or meadow growth, will also remove zinc from rainwater runoff.

If you need more information or have further questions please feel free to contact AEP Span's Marketing Department at (916) 376-2893.

Sincerely, AEP Span

John Provencal Marketing Manager

ZINCALUME® is a registered trademark of BlueScope Steel Galvalume® is a registered trademark of BIEC International, Inc.

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AEP SPAN TECHNICAL BULLETIN #35
PRESTIGE SERIES CLIP Revision 2.0 8118111

24ga PS-12 Panel at lOOpsftest point (138psf max obtained)

A clip has been added to the Prestige Series (PS-12) offering to improve panel performance. The clip is required for use in most applications to meet typical wind design loads.
FEATURES AND BENEFITS:
Durable 16ga, G90 galvanized steel construction to resist
high wind loads.
Low proﬁle - works with all prestige panel proﬁles, and in
both horizontal and vertical applications.
Can be used with all common Prestige Series installations over studs/girts, plywood and other solid substrates.
Features spring tab on one end to prevent male panel leg from backing out of adjoining panel; hold down clamp on opposite end to keep female panel leg from springing open during uplift loads.
Majority of projects will work at wide clip spacings -average design loads of 36psf for 24ga and 46psf for 22ga at 7.5ft spans (refer to test report for speciﬁc values).
Clip design accepts #10 pan head fasteners up to #14 lap
screws.

CLIP INSTALLATION
Locate clip mounting hole over fastener locating groove on adjoining panel (See Fig. 2). Drive fastener through clip and panel, and into substrate. Ensure that clip is perpendicular to panel edge. There is a centerline indicator stamped above
and below the mounting hole to assist with perpendicular clip alignment (clip design allows for positioning of clip to be approximately 90° ± 3°). In vertical panel installations, or instances where second hand is not available to hold clip, the clip can be rotated into the perpendicular position after the fastener is partially driven.

Once clip has been positioned perpendicular to adjoining panel, fasten hold down end of clip with remaining fastener(s).

Engage next Prestige Series panel by lying next to previously installed panel as shown in Fig. 3 and slide together until completely engaged. An audible “click” will be heard when panel is fully locked behind clip. Because of the clip’s low- proﬁle design, this engagement is possible with panel ends contained within C-metal trims.

NOTES:
PS-12 clip is required for use in most jobs that require engineering. 22 and 24ga panels without clips are only rated for design loads of approximately 15 and 10psf respectively (refer to test reports for speciﬁc values).
Clip is currently only available for use in 22 and 24ga applications. It has not been evaluated for use with 18 & 20ga panels (increased eﬀort required to engage 18 & 20ga panels with this clip).
Shorter clip spacings will increase eﬀort to engage panels

– use the widest clip spacing that will still meet wind load
requirements.

Submitted by: bmg
Date: 6/10/2009, Revised 8/18/11