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SynC · SynC Standards

Exterior Painting and Coatings

Rev9
IssuedOct 12, 2026
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1 Scope

NOTE This standard governs the surface preparation, priming, and finish coating of exterior architectural substrates in the field, where the coating is selected for weather resistance, color, and sheen rather than for chemical, immersion, or industrial washdown service. (1.1)
1.2 The furnished work shall comprise the surface preparation, primers, intermediate coats, finish coats, mildew treatment, touch-up, protection of adjacent work, and the field verification this standard requires, on every exterior surface the exterior elevations and the exterior finish schedule identify as field coated.
NOTE The substrates this standard coats are the following. (1.3)
  • Cast-in-place concrete, precast concrete scheduled for a field coating, and concrete masonry
  • Portland cement plaster (stucco) with a finish coat left unpigmented for coating under Plaster And StuccoPortland Cement Plaster and StuccoResolves to the current adopted revision.sync/plaster-and-stucco
  • Hollow metal doors and frames, miscellaneous metals, metal fabrications, and exposed structural steel delivered with a shop or factory primer
  • Galvanized steel, including the factory-primed curtains, hoods, and guides of coiling doors and the factory-primed sections of sectional doors, and aluminum and other non-ferrous metals scheduled for a field finish
  • Wood siding, trim, soffits, fascia, exterior millwork, and wood doors delivered unfinished, factory sealed, or factory primed for a field finish
  • Fiber-cement siding and trim
  • Previously painted exterior surfaces of any of these substrates
NOTE The boundary with High Performance CoatingsHigh-Performance CoatingsResolves to the current adopted revision.sync/high-performance-coatings is the service, not the resin. A two-component polyurethane finish on a railing in a coastal town is architectural painting and is governed here; the same resin on a tank, a containment wall, or a surface washed down with chemicals is a high-performance system and is governed there. Where a surface sees chemical splash, immersion, or industrial washdown, the whole system for that surface is selected under that standard. (1.4)
NOTE The shop coat ends at the fabricator's door and the site work begins here. The shop coat on structural steel is governed by Structural Steel FramingStructural Steel FramingResolves to the current adopted revision.sync/structural-steel-framing and Shop Painting And GalvanizingShop Painting and Galvanizing of SteelResolves to the current adopted revision.sync/shop-painting-and-galvanizing, on miscellaneous metals by Miscellaneous MetalsMiscellaneous MetalsResolves to the current adopted revision.sync/miscellaneous-metals, and on metal fabrications by Metal FabricationsMetal FabricationsResolves to the current adopted revision.sync/metal-fabrications; the factory prime coat on hollow metal is governed by Exterior Doors And FramesHollow Metal Doors and FramesResolves to the current adopted revision.sync/exterior-doors-and-frames and Doors Frames And HardwareDoors, Frames, and HardwareResolves to the current adopted revision.sync/doors-frames-and-hardware. This standard governs everything laid over those coats, and its warranty covers what it lays down and not the coat beneath. (1.5)
1.6 The Contractor shall obtain from each fabricator and door manufacturer the generic type and product identity of the shop or factory primer on every item scheduled for a field finish before the coating system schedule is submitted.
1.7 Where a substrate standard imposes a longer cure, a cleaner surface, or a tighter moisture limit than this standard, the more stringent requirement shall govern.

2 Referenced Standards

2.1 Materials, surface preparation, and application shall comply with the latest adopted edition of each of the following unless a specific edition is cited.
2.2 Where referenced standards conflict, the more stringent requirement shall govern unless the Architect directs otherwise in writing.
Standard Title
MPI Architectural Painting Specification Manual Master Painters Institute exterior system numbers, product categories, Approved Products List, and gloss levels
ASTM D16 Terminology for Paint, Related Coatings, Materials, and Applications
SSPC-SP 1 Solvent Cleaning
SSPC-SP 2 Hand Tool Cleaning
SSPC-SP 3 Power Tool Cleaning
SSPC-SP 6/NACE No. 3 Commercial Blast Cleaning
SSPC-SP 7/NACE No. 4 Brush-Off Blast Cleaning
SSPC-SP 10/NACE No. 2 Near-White Metal Blast Cleaning
SSPC-SP 11 Power Tool Cleaning to Bare Metal
SSPC-SP 13/NACE No. 6 Surface Preparation of Concrete
SSPC-SP 16 Brush-Off Blast Cleaning of Coated and Uncoated Galvanized Steel, Stainless Steels, and Non-Ferrous Metals
SSPC-PA 2 Procedure for Determining Conformance to Dry Coating Thickness Requirements
ASTM D4258 Practice for Surface Cleaning Concrete for Coating
ASTM D4259 Practice for Abrading Concrete
ASTM D4262 Test Method for pH of Chemically Cleaned or Etched Concrete Surfaces
ASTM D4263 Test Method for Indicating Moisture in Concrete by the Plastic Sheet Method
ASTM D4444 Test Method for Laboratory Standardization and Calibration of Hand-Held Moisture Meters
ASTM D3359 Test Methods for Rating Adhesion by Tape Test
ASTM D7091 Practice for Nondestructive Measurement of Dry Film Thickness of Nonmagnetic Coatings Applied to Ferrous Metals and Nonmagnetic, Nonconductive Coatings Applied to Non-Ferrous Metals
ASTM D523 Test Method for Specular Gloss
ASTM D2244 Practice for Calculation of Color Tolerances and Color Differences from Instrumentally Measured Color Coordinates
ASTM D3273 Test Method for Resistance to Growth of Mold on the Surface of Interior Coatings in an Environmental Chamber
ASTM D3274 Test Method for Evaluating Degree of Surface Disfigurement of Paint Films by Fungal or Algal Growth, or Soil and Dirt Accumulation
ASTM D6904 Practice for Resistance to Wind-Driven Rain for Exterior Coatings Applied on Masonry
ASTM D6578 Practice for Determination of Graffiti Resistance
ANSI/SDI A250.10 Test Procedure and Acceptance Criteria for Prime Painted Steel Surfaces for Steel Doors and Frames
40 CFR Part 59, Subpart D National Volatile Organic Compound Emission Standards for Architectural Coatings
OTC Model Rule for Architectural and Industrial Maintenance Coatings Ozone Transport Commission
CARB Suggested Control Measure for Architectural Coatings California Air Resources Board
SCAQMD Rule 1113 Architectural Coatings
40 CFR Part 745 Lead-Based Paint Poisoning Prevention in Certain Residential Structures
29 CFR 1926.62 Lead in Construction
NOTE The MPI manual assigns a product number to each generic coating type that passes a defined set of performance tests, and an exterior system number to each combination of substrate, primer, and finish, so a coating can be specified by performance class without naming a manufacturer. The Approved Products List names the products from competing manufacturers that have passed the tests for each number. The surface preparation standards once published by SSPC and NACE are now maintained by AMPP; the SP numbers remain in use and are cited here. (2.3)

3 Submittals

3.1 Action Submittals

3.1.1 The submittals listed below shall be reviewed and returned before any coating material is ordered or applied.
  • Product data for every primer, intermediate, and finish product, stating the generic resin type, the MPI product number where one applies, the substrates the product is published for, the wet and dry film thickness per coat, the spreading rate, the minimum and maximum recoat times, the application temperature and humidity limits, the dry-to-rain time, and the volatile organic compound content in grams per liter
  • Coating system schedule assigning to every exterior substrate and surface condition the surface preparation grade, the primer, the finish, the number of coats, the total dry film thickness, the sheen, and the MPI exterior system number where one applies
  • Color drawdowns of every color and sheen scheduled, on the substrate material or on a card the manufacturer publishes for the purpose, at the number of coats and film build the schedule requires, not smaller than 8 in. by 10 in.
  • Surface preparation plan for any abrasive blasting or coating removal, describing containment, dust control, protection of adjacent property, and disposal of spent abrasive and removed coating
Action Submittals Requiredcheckbox
☑ Product data for every coating product
☑ Coating system schedule by substrate
☑ Color drawdowns of every color and sheen
☐ Surface preparation plan for blasting or coating removal
3.1.2 The Architect's acceptance of a drawdown shall establish the color and sheen standard for the surfaces it represents, and no material shall be tinted in bulk before the drawdown for that color is accepted.

3.2 Informational Submittals

3.2.1 The Contractor shall submit the following for record, without waiting for return, before the corresponding work begins.
  • Applicator qualification statement listing the comparable projects the Applicator Qualification article requires
  • The field coating manufacturer's written confirmation that each field system is compatible with the shop or factory primer identified on each item it will cover, and, where stucco is coated, with the stucco finish coat
  • The form of the daily environmental condition log, and the completed logs as the work proceeds
  • Safety data sheets for every product
  • The manufacturer's certification of the volatile organic compound content of every product against the regulatory basis selected under Volatile Organic Compounds
  • The record of mock-up acceptance, where a mock-up is required
Informational Submittals Requiredcheckbox
☑ Applicator qualification statement
☑ Primer and stucco compatibility confirmations
☑ Environmental condition logs
☑ Safety data sheets
☑ Volatile organic compound certifications
☐ Mock-up acceptance record

3.3 Closeout Submittals

3.3.1 The Contractor shall submit the following before final acceptance.
  • Record coating schedule stating, for every coated surface, the product and MPI number applied, the color name and tint formula, the sheen, the number of coats, and the dry film thickness measured
  • The manufacturer's published product warranty for every product that carries one, executed in the Owner's name where the manufacturer issues a project warranty
  • The Contractor's warranty under the Warranty section
  • Maintenance instructions stating the cleaning methods and cleaning agents the coating tolerates, the touch-up procedure, and the recoat interval for each system
  • The Owner's signed receipt for the extra stock delivered
Closeout Submittals Requiredcheckbox
☑ Record coating schedule
☑ Manufacturer product warranties
☑ Contractor warranty
☑ Maintenance and recoat instructions
☑ Extra stock receipt

4 Quality Assurance

4.1 Applicator Qualification

4.1.1 Exterior coating work shall be performed by an applicator that has completed exterior coating work of comparable substrate, system, and extent on not fewer than the number of projects indicated in the datasheet within the five years preceding the bid.
Comparable Projects Completed by the Applicatorrange
projects
010
4.1.2 Where the manufacturer's published warranty on an elastomeric, two-component, or mineral silicate system is conditioned on application by an applicator the manufacturer has approved, the applicator shall hold that approval before the system is applied.
NOTE A value of zero waives the experience requirement and leaves qualification to the bid. Elastomeric, two-component polyurethane, and mineral silicate systems depend on mixing ratios, induction times, pot life, and wet-film control that general painting labor does not routinely practice, and an error in them shows up as a film failure under weather a season later rather than as a visible defect at acceptance, which is why the count is raised where those systems carry a large share of the work. (4.1.3)

4.2 MPI Listing

4.2.1 Each coating product shall meet the performance of the MPI product category assigned to its position in the coating system schedule, and whether listing on the MPI Approved Products List is required shall be as indicated in the datasheet.
MPI Approved Products Listradio
● Every product listed on the current MPI Approved Products List for its MPI number
○ Products meeting the MPI performance category, listing not required
NOTE Requiring the listing puts the performance test in MPI's laboratory and leaves the submittal reviewer to check a number against a list, and it limits the bid to the listed products of each manufacturer. Accepting unlisted products that meet the category admits regional and newly introduced products, and it moves the burden of judging the manufacturer's test data onto the submittal review. (4.2.2)

4.3 Single Source

4.3.1 The primer, intermediate, and finish coats within each coating system shall be products of one manufacturer, unless the datasheet permits coats from different manufacturers.
Coating System Sourcingradio
● One manufacturer for every coat of each system
○ Primer and finish from different manufacturers with written compatibility confirmation from both
4.3.2 Where coats from different manufacturers are permitted, the Contractor shall obtain the written confirmation of both manufacturers that the coats are compatible over the specified substrate and preparation, and shall submit it before either coat is applied.
NOTE A manufacturer warrants the film it formulated as a system and declines a film built from another manufacturer's primer, so a mixed system carries only the Contractor's warranty. Shop and factory primers delivered on products from other trades are outside this rule; their compatibility with the field system is handled under the Shop and Factory Primers article. (4.3.3)

4.4 Field Mock-Up

4.4.1 The mock-up program shall be as indicated in the datasheet.
Mock-Up Programselect
No mock-up required
One mock-up of each coating system
One mock-up of each coating system in each color
One mock-up of each coating system on each substrate in each color
4.4.2 Each mock-up shall be applied on the actual substrate at a location the Architect designates, over an area not less than indicated in the datasheet, and shall show the full surface preparation, primer, and finish coats at the specified sheen and color.
Mock-Up Arearange
ft²
2550100200400
Default: Not less than 100 ft²
4.4.3 The mock-up shall be viewed in daylight before acceptance, and the accepted mock-up shall be the standard of appearance and workmanship for the production work.
4.4.4 The accepted mock-up shall remain in place and protected until the work is accepted, and may remain as part of the completed work where the Architect designates it in writing.
NOTE A drawdown shows a color on a flat card; a mock-up shows it on the texture of the wall, in the sun, next to the adjacent materials, which is where a stucco or block color is actually judged. One mock-up per system settles the appearance of the film; one per color adds the color judgment, which matters where several wall colors meet; one per substrate per color adds the texture difference between, for example, the same color on smooth concrete and on split-face block. Each step adds cost and schedule, and the program is sized to the number of colors and substrates the elevations carry. (4.4.5)

4.5 Pre-Application Conference

4.5.1 Whether a pre-application conference is held before exterior coating begins shall be as indicated in the datasheet.
Pre-Application Conferenceradio
○ Conference required before exterior coating begins
○ No conference required
4.5.2 Where a conference is required, the Contractor shall convene it with the applicator, the coating manufacturer's representative, and the installers of the substrates to be coated, and the conference shall review the coating system schedule, the shop and factory primers identified, the surface preparation plan, the mock-up program, the weather limits, and the inspection hold points.
NOTE The conference is where the fabricator's primer, the stucco installer's cure, and the painter's system meet for the first time on most projects, and it is cheaper than the compatibility failure it prevents. It is held where several trades deliver primed or cementitious substrates to be coated, and skipped where the scope is a single substrate. (4.5.3)

5 Environmental and Service Conditions

5.1 Weather Limits During Application

5.1.1 Coatings shall not be applied when the air temperature or the surface temperature is below the minimum indicated in the datasheet, or above the maximum the manufacturer publishes for the product.
Air and Surface Temperature During Applicationrange
°F
35404550
Default: Not less than 50 °F
5.1.2 The temperature limits shall be maintained from the start of application until the coat has reached the manufacturer's published dry-to-recoat time.
NOTE Below its minimum film-forming temperature a waterborne coating does not coalesce: the polymer particles never fuse into a continuous film, and the coat looks acceptable when applied and fails early. Conventional waterborne products hold that minimum at 50°F; formulations rated to 35°F are available from several manufacturers at a premium and with a longer dry time, and they are selected where the schedule puts the work into a shoulder season. Above the published maximum, water or solvent flashes off before the film levels, producing dry spray and lap marks, and a surface in direct sun can exceed the air temperature by 30°F or more. (5.1.3)
5.1.4 Coatings shall not be applied when the relative humidity exceeds the value indicated in the datasheet.
Relative Humidity During Applicationrange
%
7095
Default: Not more than 85 %
5.1.5 Coatings shall not be applied unless the surface temperature is at least 5°F above the dew point, and application shall stop when the margin closes or condensation forms during the dry time.
5.1.6 Coatings shall not be applied when rain, fog, frost, or dew is present on the surface or is forecast within the manufacturer's published dry-to-rain time for the coat.
5.1.7 Coatings shall not be applied in wind that causes dry spray, carries overspray onto adjacent surfaces or property, or deposits dust or debris in the wet film.
5.1.8 The Contractor shall measure and record the air temperature, the surface temperature, the relative humidity, and the dew point at the start of each application period and at intervals not exceeding four hours while application continues, and shall include the record in the informational submittals.

5.2 Substrate Moisture and Cure

5.2.1 Concrete, concrete masonry, and stucco shall have cured not less than the number of days indicated in the datasheet before a coating is applied, unless the coating manufacturer publishes a shorter interval for the product and a moisture test under this article confirms the substrate is within the manufacturer's limit.
Cure of Cementitious Substrates Before Coatingrange
days
7142128
Default: Not less than 28 days
5.2.2 Cementitious substrates shall be tested for moisture by ASTM D4263 before coating and shall show no condensation beneath the sheet; where an electronic moisture meter calibrated to ASTM D4444 is used in its place, the reading shall not exceed the value indicated in the datasheet.
Moisture Reading of Cementitious Substratesrange
%
816
Default: Not more than 12 %
5.2.3 The surface pH of concrete, masonry, and stucco shall be tested by ASTM D4262 before priming, and a surface whose pH exceeds the primer manufacturer's published limit shall be allowed to cure further or shall receive an alkali-resistant primer the manufacturer publishes for that pH.
5.2.4 Exterior wood shall not be coated when its moisture content, measured with a meter calibrated to ASTM D4444, exceeds the value indicated in the datasheet.
Moisture Content of Wood Before Coatingrange
%
1219
Default: Not more than 15 %
NOTE Fresh concrete and stucco carry free water and a surface alkalinity that attack a film from behind: the water blisters it and the alkali saponifies an alkyd binder and burns the color out of a pigment. Twenty-eight days is the age at which ordinary portland cement surfaces have dropped to a pH and a moisture level most primers tolerate; the shorter intervals are used with primers the manufacturer publishes for green concrete and are confirmed by test rather than by the calendar. Wood above about 15 percent moisture pushes water through a new film as it dries and lifts it. (5.2.5)

6 Coating Systems by Substrate

6.1 System Selection

6.1.1 The coating system for each substrate shall be as indicated in the datasheets of this section, and the coating system schedule shall assign a system to every exterior surface scheduled for coating.
6.1.2 Each system shall consist of the primer this standard or the manufacturer requires for the substrate, plus the number of finish coats indicated under Number of Coats and Film Thickness.
NOTE No single exposure fact selects the system. A site within a few miles of salt water, downwind of an industrial stack, or under a tree canopy that keeps a north wall damp changes which option in each datasheet below holds its color and film, and the notes under each field state the trade-off against those conditions so the engineer can read the site against them. (6.1.3)

6.2 Concrete, Concrete Masonry, and Stucco

6.2.1 The finish coat system on concrete, concrete masonry, and stucco shall be as indicated in the datasheet.
Finish System on Concrete, Masonry, and Stuccoselect
Exterior 100 percent acrylic latex
Elastomeric acrylic
High-build acrylic
Waterborne acrylic-epoxy
Mineral silicate paint
NOTE A 100 percent acrylic latex is the breathable decorative film on sound cementitious walls: it holds color under ultraviolet, lets vapor out of the wall, and is the lowest-cost system to apply and to recoat. An elastomeric acrylic is applied at several times that thickness and stretches across hairline cracks and resists wind-driven rain, which is why it is selected on stucco and on walls that have cracked or leaked; it is less permeable, so it is kept off walls that get wet from behind, and it shows substrate texture less and dirt more. A high-build acrylic fills texture and pinholes on rough block and board-formed concrete at a thickness between the two. A waterborne acrylic-epoxy resists scrubbing and staining at a loading dock or a trash enclosure and chalks faster than acrylic in full sun. A mineral silicate paint bonds chemically to the mineral substrate, is fully vapor-open, and does not peel, which is why it is selected on historic masonry and unpainted lime or cement substrates; it cannot be applied over an existing organic film, and it is sold by fewer manufacturers. (6.2.2)
6.2.3 Alkyd coatings shall not be applied to concrete, concrete masonry, or stucco, because the alkalinity of the substrate saponifies the alkyd binder.
6.2.4 The primer on concrete and stucco shall be as indicated in the datasheet.
Primer on Concrete and Stuccoselect
Alkali-resistant acrylic primer-sealer
Penetrating masonry surface conditioner
First coat of the finish material applied as a self-primer
NOTE An alkali-resistant acrylic primer-sealer seals a porous surface, evens the absorption so the finish dries uniformly, and tolerates a pH higher than a finish coat does, which is why it is selected on new stucco and concrete coated near the end of the cure period. A penetrating surface conditioner binds a chalky or weathered surface that would otherwise shed a film, and it is selected on recoat work and on stucco that has weathered unpainted for a season. Elastomeric and some high-build systems are published as self-priming on a sound, cured surface, and the first coat of the finish then serves as the primer and saves a product and a day; the manufacturer's data sheet states when that is permitted, and the pH test governs where the substrate is young. (6.2.5)
6.2.6 Whether concrete masonry receives a block filler shall be as indicated in the datasheet.
Block Filler on Concrete Masonryradio
● High-build block filler before the primer or first finish coat
○ No block filler
6.2.7 Block filler shall be applied by roller or by spray with back-rolling, in the quantity needed to fill the surface voids of the masonry and present a continuous surface to the coat that follows.
NOTE Concrete masonry is open-celled, and finish coats applied straight to it sink into the voids, leave pinholes, and never form a continuous weather film. A block filler closes the texture at a fraction of the finish material's cost per mil. It is omitted where the units were factory prefilled or sealed, where a high-build finish system is itself published to fill the texture, or where the open texture is the appearance the design wants and a water repellent rather than a film is specified under the masonry standard. (6.2.8)
6.2.9 Elastomeric coatings shall be applied in not fewer than two coats to a total dry film thickness not less than indicated in the datasheet, and shall be products tested for wind-driven rain resistance by ASTM D6904.
Total Dry Film Thickness of Elastomeric Coatingsrange
mils
8101214162024
NOTE An elastomeric film bridges cracks only at the thickness the manufacturer tested it at, and the published values run from about 10 mils for a two-coat decorative elastomeric to 20 mils and more for a system warranted against water intrusion. The thickness is set from the product data of the system selected and from whether the wall has an active crack pattern to bridge. (6.2.10)
6.2.11 Coatings shall not be applied to stucco until the Contractor has obtained the stucco finish coat manufacturer's written confirmation that the finish coat is compatible with the coating system, as Plaster And StuccoPortland Cement Plaster and StuccoResolves to the current adopted revision.sync/plaster-and-stucco requires.
6.2.12 Where architectural precast concrete is scheduled for a field coating, the Contractor shall confirm with the precast supplier that no sealer or water repellent has been applied to the units under Architectural Precast ConcreteArchitectural Precast ConcreteResolves to the current adopted revision.sync/architectural-precast-concrete that the primer manufacturer does not publish the primer as bonding to.

6.3 Ferrous Metal

6.3.1 Bare ferrous metal, and the bare areas of shop-primed or factory-primed ferrous metal, shall be solvent cleaned to SSPC-SP 1 and then prepared to the grade indicated in the datasheet before priming.
Surface Preparation Grade for Bare Ferrous Metalselect
SSPC-SP 2, Hand Tool Cleaning
SSPC-SP 3, Power Tool Cleaning
SSPC-SP 11, Power Tool Cleaning to Bare Metal
SSPC-SP 7, Brush-Off Blast Cleaning
SSPC-SP 6, Commercial Blast Cleaning
SSPC-SP 10, Near-White Metal Blast Cleaning
NOTE Hand and power tool cleaning remove loose rust, loose mill scale, and loose coating and leave the tight material in place; they are the grades a field crew reaches on a railing, a lintel, or a door frame without containment, and they serve an alkyd or acrylic primer that tolerates a tight residue. Power tool cleaning to bare metal removes everything but leaves no anchor profile, which an epoxy primer accepts and a zinc-rich primer does not. Brush-off blast removes loose material and roughens the surface with the least abrasive and containment. Commercial blast removes all but staining and gives the profile an epoxy primer bonds to, and near-white blast is the grade zinc-rich primers and the long-life systems for coastal and industrial exposure are published for; both require containment and disposal planned under the surface preparation plan. (6.3.2)
6.3.3 Solvent cleaning to SSPC-SP 1 shall precede every other preparation grade, because abrasive or mechanical cleaning over oil or grease drives the contaminant into the profile.
6.3.4 The field primer on ferrous metal shall be as indicated in the datasheet.
Field Primer on Ferrous Metalselect
Rust-inhibitive alkyd primer
Waterborne acrylic rust-inhibitive primer
Epoxy primer
Organic zinc-rich primer
NOTE A rust-inhibitive alkyd primer wets a hand-cleaned surface and tolerates tight rust, and it is restricted or unavailable where the volatile organic compound basis is strict. A waterborne acrylic rust-inhibitive primer meets every current limit, dries fast, and needs a cleaner, drier surface and a warmer day. An epoxy primer builds a thicker barrier and bonds a polyurethane finish, and it needs a blast-cleaned surface and a recoat window the schedule has to respect. An organic zinc-rich primer protects the steel galvanically at a scratch and is the primer under the systems selected for coastal and industrial sites, at the cost of near-white blasting and a two-component mix. (6.3.5)
6.3.6 Epoxy primers shall be applied only over a surface cleaned to SSPC-SP 6 or cleaner, and zinc-rich primers only over a surface cleaned to SSPC-SP 10 or cleaner, unless the primer manufacturer publishes a less stringent grade for the product.

6.4 Metal Finish Coats

6.4.1 The finish coat system on ferrous, galvanized, and non-ferrous metal shall be as indicated in the datasheet.
Finish System on Metalselect
Exterior acrylic latex, direct-to-metal grade
Alkyd enamel
Waterborne acrylic-urethane
Two-component aliphatic polyurethane over an epoxy primer
Waterborne acrylic-epoxy
NOTE An exterior acrylic latex of direct-to-metal grade holds its color and gloss under ultraviolet, tolerates the movement of a door or a railing, and meets every volatile organic compound limit, and it marks and burnishes more easily than a harder resin. An alkyd enamel levels to the smoothest brushed finish and hardens over weeks, chalks and yellows in sun, and is restricted where the volatile organic compound basis is strict. A waterborne acrylic-urethane sits between them in hardness and gloss retention at a waterborne volatile organic compound content. A two-component aliphatic polyurethane over an epoxy primer holds gloss and color longest, resists abrasion and salt, and is the system selected for railings and exposed steel on coastal and industrial sites; it requires the preparation its primer demands, a two-component mix, and a trained applicator. A waterborne acrylic-epoxy resists scrubbing and staining on a frequently cleaned door or frame and chalks in full sun. (6.4.2)
6.4.3 Where a two-component aliphatic polyurethane finish is selected, the primer shall be an epoxy or zinc-rich primer the finish manufacturer publishes for the system, and the surface preparation shall be the grade that primer requires.
NOTE Where a metal surface sees chemical splash, immersion, or industrial washdown, its coating system is selected under High Performance CoatingsHigh-Performance CoatingsResolves to the current adopted revision.sync/high-performance-coatings rather than from this datasheet. (6.4.4)

6.5 Galvanized Steel

6.5.1 Galvanized steel shall be solvent cleaned to SSPC-SP 1 and then cleaned of its passivating treatment, storage oils, and white rust by the method the primer manufacturer publishes, and shall be given a profile by SSPC-SP 16 where the primer manufacturer requires one, before priming.
6.5.2 The primer on galvanized steel shall be as indicated in the datasheet.
Primer on Galvanized Steelselect
Waterborne acrylic primer formulated for galvanizing
Vinyl wash primer
Epoxy primer formulated for galvanizing
Acrylic direct-to-metal finish applied as its own primer
NOTE New galvanizing carries a chromate passivation and rolling oils that shed ordinary primers, and zinc saponifies an alkyd binder. A waterborne acrylic primer formulated for galvanizing bonds to a cleaned zinc surface without etching, meets every volatile organic compound limit, and is what most manufacturers publish under their acrylic and acrylic-urethane finishes. A vinyl wash primer etches the zinc chemically and is the traditional base under an alkyd or polyurethane system where the strict volatile organic compound bases do not apply. An epoxy primer formulated for galvanizing is the base under a two-component polyurethane finish where that system is selected for the exposure. Several direct-to-metal acrylics are published as self-priming on cleaned galvanizing and save a coat on weathered galvanizing that has lost its passivation; the manufacturer's data sheet states whether new, bright galvanizing is included. (6.5.3)
6.5.4 Alkyd primers and alkyd finish coats shall not be applied directly to galvanized steel.
6.5.5 The factory-primed curtains, hoods, and guides of coiling doors under Overhead Coiling DoorsOverhead Coiling DoorsResolves to the current adopted revision.sync/overhead-coiling-doors and the factory-primed sections of sectional doors under Sectional Overhead DoorsSectional Overhead DoorsResolves to the current adopted revision.sync/sectional-overhead-doors, where scheduled for a field finish, shall receive the finish system selected under Metal Finish Coats over the factory primer, after the compatibility confirmation the Shop and Factory Primers article requires.

6.6 Aluminum and Other Non-Ferrous Metal

6.6.1 Mill-finish aluminum, copper alloys, and other non-ferrous metals scheduled for a field finish shall be solvent cleaned to SSPC-SP 1 and primed as indicated in the datasheet.
Primer on Aluminum and Other Non-Ferrous Metalselect
Waterborne acrylic bonding primer for non-ferrous metal
Vinyl wash primer
Epoxy primer formulated for non-ferrous metal
Not applicable, no non-ferrous metal scheduled for a field finish
NOTE A waterborne acrylic bonding primer wets a cleaned aluminum surface and carries an acrylic or acrylic-urethane finish at the lowest volatile organic compound content. A vinyl wash primer etches the oxide and is the base under an alkyd or polyurethane finish. An epoxy primer formulated for non-ferrous metal is the base under a two-component polyurethane system. Field painting of mill aluminum is uncommon because most architectural aluminum arrives anodized or factory coated; the field selection covers mill-finish trim, conduit, louvers, and repairs. (6.6.2)
6.6.3 Factory-finished aluminum and other factory-finished non-ferrous metal shall not be field painted unless the Contract Documents direct it, because a field coating over an anodic or fluoropolymer finish voids the finish warranty and does not bond without a treatment the finish manufacturer approves.

6.7 Wood

6.7.1 The finish type on exterior wood shall be as indicated in the datasheet.
Finish Type on Exterior Woodselect
Opaque 100 percent acrylic latex paint
Opaque alkyd paint
Solid-color acrylic stain
Semi-transparent penetrating stain
Transparent water-repellent finish
Film-forming exterior clear finish
NOTE An opaque acrylic paint builds a flexible film that moves with the wood, holds color, and lasts longest among the opaque finishes on siding and trim. An opaque alkyd paint penetrates weathered wood and levels on trim and doors, and it embrittles and chalks sooner and is restricted where the volatile organic compound basis is strict. A solid-color stain hides the grain while showing the texture and fails by erosion rather than by peeling, so it recoats without scraping. A semi-transparent penetrating stain shows the grain, lasts two to four years on a weather face, and recoats by cleaning and reapplying. A transparent water-repellent finish keeps the natural color for a season or two and is the finish for wood intended to weather to gray with less checking. A film-forming clear finish shows the wood at its best and fails by peeling under ultraviolet within a few years on any face the sun reaches, so it is kept to protected soffits and doors under a deep overhang. (6.7.2)
6.7.3 The primer under an opaque finish on exterior wood shall be as indicated in the datasheet.
Primer on Exterior Wood Under an Opaque Finishradio
○ Alkyd stain-blocking exterior wood primer
○ Acrylic stain-blocking exterior wood primer
NOTE An alkyd wood primer penetrates and seals the grain, blocks tannin and extractive bleed on cedar and redwood more completely, and takes longer to dry. An acrylic wood primer stays flexible with the wood, meets the strict volatile organic compound bases, and blocks bleed well on most species with a second coat on the heaviest-bleeding ones. (6.7.4)
6.7.5 Knots, sap streaks, and resinous areas shall be spot sealed with a stain-blocking sealer before the primer, and nail holes and surface defects shall be filled after priming and before the finish coats.
6.7.6 Cut ends and end grain of wood siding and trim exposed by site cutting shall be primed before the piece is installed where the end is accessible, and sealed with the primer where it becomes accessible only after installation.
6.7.7 Wood doors delivered unfinished or factory sealed under Wood DoorsWood DoorsResolves to the current adopted revision.sync/wood-doors shall be finished on all six surfaces, including the top and bottom edges and every cutout, within the interval after hanging that the door manufacturer publishes.
6.7.8 Factory-primed wood and fiber-cement siding and trim shall receive the finish coats within the exposure period the primer manufacturer publishes for the factory primer, and the factory primer shall be spot primed where it is cut, abraded, or weathered beyond that period.
6.7.9 Fiber-cement siding and trim shall receive a 100 percent acrylic latex finish, and unprimed fiber cement shall receive an alkali-resistant acrylic primer before the finish coats.
NOTE Fiber-cement manufacturers condition their finish warranties on a 100 percent acrylic topcoat and publish an alkali-resistant acrylic primer for unprimed material, because the cement content of the board attacks other binders the way fresh concrete does, and an elastomeric film is too impermeable for the board. (6.7.10)
NOTE A dark color on a wood or fiber-cement face in direct sun raises the surface temperature by tens of degrees, which drives moisture out of the wood faster, opens checks, and shortens the film's life; the finish schedule limits the light reflectance value of colors on such faces where the manufacturer's warranty does. (6.7.11)

6.8 Previously Painted Surfaces

6.8.1 Before a previously painted surface is recoated, the Contractor shall assess the soundness of the existing coating and test its adhesion by ASTM D3359 at not fewer than three locations per substrate and existing coating type, plus one location per additional 1,000 ft² of that surface.
6.8.2 The disposition of the existing coating shall be as indicated in the datasheet.
Disposition of Existing Coatingradio
○ Spot preparation of failed areas and overcoat of the sound film
○ Complete removal of the existing coating to the substrate
NOTE Overcoating a sound film costs a fraction of removal and is what most recoat work does: the failed areas are scraped and feathered, the sound film is cleaned and dulled, and the new system goes over both. Complete removal is selected where the adhesion test fails across the surface, where the existing film is an incompatible type such as an aged alkyd under a strict volatile organic compound basis that forbids its match, where the film has built up to the point that it cracks, or where a mineral silicate or elastomeric system that cannot go over an organic film is selected. (6.8.3)
6.8.4 Loose, peeling, blistered, cracked, and alkali-burned coating shall be removed to a sound edge, and the edge shall be feathered so that the repair does not telegraph through the finish.
6.8.5 Chalk shall be washed from the surface, glossy sound film shall be dulled by sanding or by a deglossing method the manufacturer publishes, and the sound film shall be cleaned of mildew, soil, and oil before priming.
6.8.6 Where the existing coating fails the adhesion test at any location, the Contractor shall report the result to the Architect before proceeding, and the Architect shall determine the extent of the surface to be removed.
6.8.7 A test patch of the proposed system shall be applied over the prepared existing coating, cured not less than seven days, and tested for adhesion by ASTM D3359 before the system is applied to the rest of the surface.
6.8.8 In a building constructed before 1978, the existing coating shall be tested for lead before any sanding, scraping, or blasting disturbs it, and a coating found to contain lead shall be handled under Hazardous Material AbatementHazardous Material AbatementResolves to the current adopted revision.sync/hazardous-material-abatement, 40 CFR Part 745 where the building is target housing or a child-occupied facility, and 29 CFR 1926.62.

6.9 Anti-Graffiti and Mildew-Resistant Finishes

6.9.1 Whether an anti-graffiti coating is applied over the finish shall be as indicated in the datasheet.
Anti-Graffiti Coatingselect
None
Sacrificial anti-graffiti coating
Non-sacrificial anti-graffiti coating
NOTE A sacrificial anti-graffiti coating is a clear wax or polysaccharide film that is removed with hot water along with the graffiti and reapplied, which keeps the cost per application low and the maintenance recurring. A non-sacrificial coating is a clear polyurethane, siloxane, or fluoropolymer film that resists repeated cleaning with solvents and stays in place, at a higher first cost and with a sheen and a darkening of the color beneath that the mock-up has to show. Both are applied to the lower portion of walls exposed to the public way, and the extent is set by the elevations. (6.9.2)
6.9.3 Where an anti-graffiti coating is selected, its extent shall be as indicated on the exterior elevations, and the product shall be tested by ASTM D6578 and published by its manufacturer as compatible with the finish coat beneath it.
6.9.4 Whether the finish coats on cementitious and wood substrates are a mildew-resistant formulation shall be as indicated in the datasheet.
Mildew Resistance of Finish Coatsradio
● Mildew-resistant formulation tested by ASTM D3273 and rated by ASTM D3274
○ No mildew-resistance requirement
NOTE Most exterior finish coats carry a mildewcide as formulated, and the requirement makes the claim testable rather than adding a product. It is waived where the Owner's environmental program excludes biocidal additives, and it is held where a shaded, damp, or north-facing elevation shows mildew on the existing finish. (6.9.5)

7 Sheen, Coats, and Film Thickness

7.1 Sheen

7.1.1 The sheen of finish coats on wall fields of concrete, masonry, stucco, and siding shall be as indicated in the datasheet, expressed as the MPI gloss level.
Sheen of Finish Coats on Wall Fieldsselect
G1, flat
G2, velvet
G3, eggshell
G4, satin
G5, semi-gloss
7.1.2 The sheen of finish coats on trim, doors, frames, railings, and other metal shall be as indicated in the datasheet, expressed as the MPI gloss level.
Sheen of Finish Coats on Trim, Doors, and Metalselect
G3, eggshell
G4, satin
G5, semi-gloss
G6, gloss
G7, high gloss
7.1.3 Gloss shall be measured by ASTM D523 at 60 degrees, and sheen at 85 degrees, against the ranges the MPI gloss levels define.
NOTE A flat or velvet finish hides the texture variation, patching, and lap marks of a large stucco or block field and soils fastest; a satin or semi-gloss finish sheds dirt and rain and shows every trowel mark and patch. On trim and metal the higher levels wash and resist handling and show the substrate's dents and weld grinding, and a gloss or high gloss alkyd or polyurethane is selected on doors and railings where that appearance is wanted. Elastomeric coatings are published in flat and low-sheen levels, and a sheen above velvet is not available in most elastomeric lines. (7.1.4)

7.2 Number of Coats and Film Thickness

7.2.1 Each coating system shall consist of its primer plus the number of finish coats indicated in the datasheet.
Number of Finish Coats Over the Primerrange
coats
13
Default: Not less than 2 coats
7.2.2 Each coat shall be applied at not less than the spreading rate and dry film thickness the manufacturer publishes for the product, and the completed system shall meet the total dry film thickness stated in the coating system schedule.
7.2.3 Where the number of coats indicated does not produce complete hide and uniform color and sheen, the Contractor shall apply additional coats at no change in the Contract Sum until it does.
NOTE Two finish coats over a primer build the film thickness the manufacturer's weathering data assume and hide the primer on most colors. A single finish coat serves a self-priming elastomeric or high-build system published for one finish coat over its own first coat, and a solid-color or semi-transparent stain applied as one coat. A third finish coat is reached for on a deep or saturated color whose pigment hides poorly, on a porous block field that drinks the first coat, and where the system's published thickness cannot be reached in two. (7.2.4)

8 Color

8.1 Colors of every coated surface shall be as indicated on the exterior finish schedule, and the Contractor shall not select or substitute a color.
8.2 Each color shall match the accepted drawdown under the Action Submittals article, and a custom or deep-tone color shall additionally be confirmed on the mock-up where one is required before bulk material is tinted.
8.3 Where the Architect and the Contractor disagree whether a cured film matches the accepted drawdown, the color difference measured by ASTM D2244 with a spectrophotometer shall not exceed the value indicated in the datasheet, and where no value is indicated the Architect's determination shall govern.
Color Difference From the Accepted Drawdownrange
ΔE
14
8.4 Bulk-tinted material of one color from different batches shall be boxed into one container and mixed before application on any continuous surface.
NOTE Deep and saturated colors fade and chalk faster than light ones, require the third coat the Number of Coats article describes, and are not available in every product line; elastomeric and fiber-cement manufacturers publish a minimum light reflectance value below which their warranty does not apply. A tolerance of about 1 ΔE is at the limit of what a tinting machine repeats and is bought for a color-critical facade; 2 ΔE is the difference a trained eye sees side by side; above 3 ΔE a repair is visible from the sidewalk. (8.5)

9 Volatile Organic Compounds

9.1 Every coating shall comply with the volatile organic compound limits in force at the project location, and the regulatory basis against which the submittals demonstrate compliance shall be as indicated in the datasheet.
Volatile Organic Compound Limit Basisselect
EPA national architectural coatings rule, 40 CFR Part 59 Subpart D
OTC model rule as adopted by the state
CARB Suggested Control Measure as adopted by the air district
SCAQMD Rule 1113
9.2 Where a limit stricter than the selected basis is in force at the project location, the stricter limit shall govern, and the Contractor shall confirm the limits in force before material is ordered.
9.3 The product data shall state the volatile organic compound content of each product in grams per liter, less water and exempt compounds, as the selected basis defines it.
NOTE The federal rule is the floor everywhere in the United States and permits alkyd primers and enamels at contents the state rules do not. The Ozone Transport Commission model rule, adopted in most northeastern and mid-Atlantic states, and the California Air Resources Board measure, adopted by most California air districts and by several other states, lower the limits for flats, non-flats, primers, and stains to levels that most alkyd products do not meet. SCAQMD Rule 1113 is the strictest and is the basis a project outside southern California selects when it wants the lowest-emitting product lines, which every national manufacturer stocks, or when a green-building rating system credits it. The selected basis changes which options in the primer and finish datasheets above remain procurable. (9.4)

10 Surface Preparation

10.1 Cleaning and Repair Common to All Substrates

10.1.1 Surface preparation of each surface shall be completed and inspected under the Inspection Hold Points article before any primer is applied to it.
10.1.2 Every surface to be coated shall be clean, dry, sound, and free of dust, dirt, oil, grease, form-release agent, curing compound, efflorescence, laitance, chalk, mildew, rust, mill scale, loose or failing coating, and any other contaminant that would impair adhesion.
10.1.3 Mildew shall be killed and removed with a solution the coating manufacturer publishes for the purpose, the surface shall be rinsed and allowed to dry, and the source of the moisture that supported it shall be reported to the Architect.
10.1.4 Efflorescence shall be removed by dry brushing followed by washing, and the surface shall not be coated until efflorescence has stopped reappearing after cleaning.
10.1.5 Cracks wider than 1/16 in. in concrete, masonry, and stucco shall be routed and sealed with an elastomeric sealant under Joint SealantsJoint SealantsResolves to the current adopted revision.sync/joint-sealants that the coating manufacturer publishes as paintable, before the primer is applied.
10.1.6 Holes, voids, tie holes, and spalls in cementitious substrates shall be filled with a cementitious or polymer-modified patching compound, cured, and profiled to match the adjacent surface before priming.
10.1.7 Hardware, fixtures, signs, cover plates, and other items not scheduled for coating shall be removed or masked before application and reinstalled or unmasked after the finish has cured, and fire door labels, nameplates, and equipment data plates shall not be coated.
10.1.8 Surfaces, landscaping, vehicles, and property adjacent to the work shall be protected from drips, spatter, and overspray, and any that is deposited shall be removed by the Contractor at its own cost without damage to the surface it landed on.
NOTE A surface that is clean but wet, or dry but chalky, or sound but glossy, fails a new film in a different way, and the preparation steps above are each aimed at one of those failures. Mildew that is painted over keeps growing and lifts the film; efflorescence that is painted over pushes the film off as the salts recrystallize; a crack that is bridged by paint alone reopens with the first thermal cycle. (10.1.9)

10.2 Concrete, Masonry, and Stucco Preparation

10.2.1 Sound, open-textured concrete, masonry, and stucco shall be cleaned by the methods of ASTM D4258.
10.2.2 Smooth, glazed, or burnished concrete, and concrete carrying a form-release agent or a curing compound, shall be abraded by ASTM D4259 or prepared by SSPC-SP 13 to a uniformly textured, absorbent surface.
10.2.3 The Contractor shall confirm the removal of form-release agents and curing compounds by observing that water sprinkled on the surface is absorbed rather than beaded, before priming.
10.2.4 Where an existing coating is being removed from a cementitious substrate, the removal method shall be one SSPC-SP 13 describes, and the surface shall be cleaned of the removal residue by ASTM D4258 before priming.
NOTE A curing compound or a form-release agent leaves a film that no primer bonds through, and it is invisible on a dry wall; the water test shows it in a minute. The abrasive and mechanical methods roughen a surface too dense to absorb a primer and remove a contaminated skin, and they are planned with containment where the dust reaches the public. (10.2.5)

10.3 Shop and Factory Primers

10.3.1 Before a finish system is applied over a shop or factory primer, the Contractor shall obtain the field coating manufacturer's written confirmation that the finish system is compatible with that primer, as the Informational Submittals article requires.
10.3.2 Where compatibility cannot be confirmed, the Contractor shall apply a tie coat the finish manufacturer publishes for the purpose over the primer, or shall remove the primer and prime the surface under the Ferrous Metal or Galvanized Steel article, as the Architect directs.
10.3.3 Damaged shop or factory primer, field welds, bolted connections, field-cut edges, and bare areas shall be cleaned to the grade selected under Ferrous Metal and spot primed with a primer the field coating manufacturer publishes as compatible with both the shop primer and the finish, before the finish coats are applied.
10.3.4 Shop-primed or factory-primed steel that has stood exposed longer than the primer manufacturer's published exposure period, or that shows rust bleeding through the primer, shall be cleaned to the grade selected under Ferrous Metal and reprimed before the finish coats.
10.3.5 Hollow metal doors and frames delivered with a factory primer to ANSI/SDI A250.10 shall be cleaned of handling soil, sanded smooth where the primer is rough or runs, spot primed where the primer is damaged, and finished with the system selected under Metal Finish Coats.
NOTE A shop primer is a shipping coat formulated to be covered, and its exposure life is weeks to months. A finish applied over a primer it does not wet lifts at the interface, and when it does, the fabricator points to the painter and the painter to the fabricator; the written compatibility confirmation and the identity of the primer on the shop drawings are what make one party answerable. Structural Steel FramingStructural Steel FramingResolves to the current adopted revision.sync/structural-steel-framing has the fabricator identify its primer for this reason and, where the field finish is known at shop drawing time, apply one the finish manufacturer publishes as compatible. (10.3.6)

11 Coating Application

11.1 Application Methods

11.1.1 The application method shall be as indicated in the datasheet.
Application Methodradio
● Spray application permitted, with back-rolling on porous substrates
○ Brush and roller only
11.1.2 Spray-applied coatings on concrete, masonry, stucco, and wood shall be back-rolled or back-brushed into the surface while the coat is wet.
11.1.3 The first coat on a porous substrate shall be worked into the surface so that it wets the voids and the texture rather than bridging them.
NOTE Spray lays a coat down fast and evenly on a large field and is the only practical method on a textured elastomeric; without back-rolling it bridges the texture of block and rough concrete and leaves pinholes and voids that let water behind the film, and it drifts onto whatever is downwind. Brush and roller alone are selected where overspray cannot be contained, on occupied sites and near parked vehicles, and on trim and railings where spray wastes more material than it applies. (11.1.4)

11.2 Recoat Windows and Film Continuity

11.2.1 Each coat shall dry for not less than the manufacturer's published minimum recoat time before the next coat is applied, and where the manufacturer publishes a maximum recoat time the next coat shall be applied within it or the surface shall be abraded or tie-coated as the manufacturer publishes.
11.2.2 Two-component materials shall be mixed in the published ratio, allowed the published induction time, and applied within the published pot life, and material that has exceeded its pot life shall be discarded.
11.2.3 The completed film shall be continuous and uniform in color, sheen, and thickness, free of runs, sags, drips, holidays, pinholes, dry spray, lap marks, brush marks, and embedded debris when viewed in daylight from a distance of 10 ft.
11.2.4 The Contractor shall maintain a wet edge and shall complete each wall plane, or each plane to a natural break such as a corner, a joint, or a change of material, in one continuous operation.
NOTE Recoating too soon traps water or solvent under the new coat and blisters it; recoating an epoxy or polyurethane after its window closes puts a new coat on a surface too hard to bond to, and the window on those products is measured in days. Lap marks appear where a dried edge is overlapped on a sunny wall, which is why a plane is finished to a break rather than to the end of the day. (11.2.5)

11.3 Touch-Up and Final Cleaning

11.3.1 After the work of other trades is complete, the Contractor shall touch up abrasions, scratches, and damage to the coated surfaces with the same product, color, and batch used on the surface, applied by the same method.
11.3.2 Where a touch-up is visible in daylight from 10 ft, the Contractor shall recoat the surface to the nearest natural break.
11.3.3 The Contractor shall remove spatter, drips, and overspray from every surface not scheduled for coating, and shall remove its materials, containers, and debris from the site at completion.

12 Testing

12.1 Film Thickness Verification

12.1.1 The coating thickness verification program shall be as indicated in the datasheet.
Coating Thickness Verificationselect
Wet film gauge readings during application on every substrate
Wet film gauge readings plus dry film measurement to SSPC-PA 2 on metal
Dry film measurement to SSPC-PA 2 on metal by an independent coating inspector
12.1.2 Dry film thickness on metal shall be measured with a gauge conforming to ASTM D7091, and dry film thickness on non-metallic substrates shall be verified by wet film gauge readings during application correlated to the product's volume solids.
12.1.3 Where a measured area is below the specified dry film thickness, the Contractor shall apply additional coats to that area until it conforms, at no change in the Contract Sum.
NOTE A wet film gauge read during application is the only thickness check available on stucco, block, and wood, and it is what architectural painting relies on. Dry film measurement to SSPC-PA 2 on metal proves the film on railings, doors, and exposed steel to a statistical sampling plan and is selected where a two-component or coastal system is being paid for. An independent inspector adds a party with no stake in the result and is selected where the metal scope is large or the Owner's warranty on the system requires third-party records. (12.1.4)

12.2 Adhesion Testing

12.2.1 The adhesion testing requirement shall be as indicated in the datasheet.
Adhesion Testing of the Applied Systemselect
Before overcoating every previously painted surface
Only where the existing coating type is unknown or a shop primer's compatibility is unconfirmed
No adhesion testing required
12.2.2 Adhesion shall be tested by ASTM D3359, by the cross-cut method for films thinner than 5 mils and the X-cut method for thicker films, on a test patch cured not less than seven days.
12.2.3 Adhesion tests shall be performed by the Contractor, and where a test fails, the retest after correction shall be at the Contractor's cost.
NOTE An adhesion test is the only field method that predicts whether a new film will stay on an old one, and it is cheap relative to the surface it qualifies. Testing every previously painted surface is selected on recoat projects where the existing films are many and undocumented; limiting it to unknown coatings and unconfirmed primers covers the two cases where compatibility is genuinely uncertain; waiving it suits new construction where every substrate is bare or carries an identified primer whose compatibility is confirmed in writing. (12.2.4)

12.3 Inspection Hold Points

12.3.1 The Contractor shall notify the Architect not less than 48 hours before each of the following stages on each substrate and shall not proceed past the stage until the Architect has inspected it or the notice period has expired without a response: completed surface preparation, completed primer, and completed finish.
NOTE Surface preparation and primer defects are invisible once the finish is on, and the hold points are the only moments at which they can be seen without destroying the finish to look. (12.3.2)

13 Delivery, Storage, and Handling

13.1 Coatings shall be delivered to the site in the manufacturer's original sealed containers, labeled with the product name, the MPI number where one applies, the color, the batch number, and the date of manufacture.
13.2 Materials shall be stored in a secure, ventilated space between 40°F and 95°F, or within the narrower range the manufacturer publishes, protected from freezing, direct sun, and open flame.
13.3 Waterborne material that has frozen shall not be used, and material that has exceeded the manufacturer's published shelf life shall be removed from the site.
13.4 Containers shall be kept closed except while material is drawn, and partly used containers shall be resealed to prevent skinning and contamination.
13.5 Mixing and storage areas shall be protected with drop cloths and spill containment, and spent solvent, rags, and surplus material shall be disposed of as the regulations in force at the project location require.
NOTE A waterborne coating that freezes breaks its emulsion and cannot be restored by thawing or stirring, and the damage is not visible in the can. Oily rags left in a pile can heat and ignite, which is why they are stored in a closed metal container. (13.6)

14 Warranty

14.1 The Contractor shall warrant the coating work against peeling, blistering, flaking, cracking, loss of adhesion, and chalking beyond the manufacturer's published rate, for not less than the period indicated in the datasheet from the date of Substantial Completion.
Contractor Warranty Period for the Coating Workrange
yr
1235
14.2 The Contractor's warranty shall cover the field-applied system, including its adhesion to the shop or factory primer the Contractor confirmed compatible, and shall not cover the shop or factory primer's adhesion to its own substrate, which remains under the warranty of the standard that governs that primer.
14.3 Where the manufacturer publishes a product or system warranty longer than the Contractor's period, the Contractor shall comply with the manufacturer's application and documentation conditions so that the Owner receives it, and the manufacturer's warranty shall apply in addition to the Contractor's.
14.4 A warranty repair shall restore the surface to match the adjacent work in color and sheen to the nearest natural break, and shall carry a fresh warranty of the original period from the date of the repair or the unexpired remainder of the original period, whichever ends later.
14.5 The Contractor shall bear the cost of removing, protecting, and reinstalling adjacent work disturbed by a warranty repair, and of repairing collateral damage the repair causes.
NOTE A one-year period matches the general correction period of most contracts and is what a project selects when the coating is one trade among many; two years carries the film through two full weather cycles, which is when preparation failures on exterior work appear; longer periods are selected on elastomeric and two-component systems whose manufacturers warrant the material for ten years and more, so that the workmanship warranty is not the shortest term on the wall. Normal weathering, fading and chalking within the manufacturer's published rate, and damage by others or by a moisture source behind the wall are outside the warranty. (14.6)

15 Extra Stock

15.1 The Contractor shall deliver to the Owner before final acceptance the quantity of each finish product, in each color and sheen used on the project, indicated in the datasheet, in sealed, labeled, original containers from the batches applied.
Extra Stock of Each Finish Product, Color, and Sheenrange
gal
05
Default: 1 gal
15.2 Each container shall be labeled with the product, the MPI number where one applies, the color name and tint formula, the sheen, and the surfaces on which it was used, so that the Owner can match a touch-up without testing.
15.3 The Contractor shall obtain the Owner's signed receipt for the extra stock and shall include it in the closeout submittals.
NOTE Exterior touch-up is harder to blend than interior because the in-place film has weathered, and material from the same batch, with the formula recorded, is the closest match the Owner will ever get; a gallon of each color serves the first few years of touch-up on most buildings, and more is delivered where the Owner's maintenance staff will touch up rather than recoat. (15.4)

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