Standard Practice for Application of Direct-Applied Exterior Finish Systems

SIGNIFICANCE AND USE
4.1 This practice provides minimum requirements for the application of Direct-applied Exterior Finish Systems. The requirements for materials, mixtures, and details shall be contained in the project plans and specifications.
SCOPE
1.1 This practice covers the minimum requirements and procedures for field application of Direct-applied Exterior Finish Systems (DEFS). Direct-applied exterior finish systems are coating systems applied over various substrates with non-metallic reinforcing mesh, in which the base coat ranges from not less than 1/16 in. (1.6 mm) to 3/32 in. (2.4 mm) in dry thickness, depending on the mass of the reinforcing mesh. This base coat is subsequently covered with a finish coat that is available in a variety of textures and colors.  
1.2 The values stated in inch-pound units are to be regarded as the standard. The metric values given in parentheses are approximate and are provided for information purposes only.  
1.3 This standard may involve hazardous materials, operations and equipment. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

Status
Historical
Publication Date
31-Mar-2017
Current Stage
Ref Project

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: C1516 − 05 (Reapproved 2017)
Standard Practice for
Application of Direct-Applied Exterior Finish Systems
This standard is issued under the fixed designation C1516; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope* C1177/C1177M Specification for Glass Mat Gypsum Sub-
strate for Use as Sheathing
1.1 This practice covers the minimum requirements and
C1186 Specification for Flat Fiber-Cement Sheets
procedures for field application of Direct-applied Exterior
C1278/C1278M Specification for Fiber-Reinforced Gypsum
Finish Systems (DEFS). Direct-applied exterior finish systems
Panel
are coating systems applied over various substrates with
C1325 Specification for Non-Asbestos Fiber-Mat Rein-
non-metallic reinforcing mesh, in which the base coat ranges
forced Cementitious Backer Units
1 3
from not less than ⁄16 in. (1.6 mm) to ⁄32 in. (2.4 mm) in dry
E1825 Guide for Evaluation of Exterior Building Wall
thickness, depending on the mass of the reinforcing mesh. This
Materials, Products, and Systems
base coat is subsequently covered with a finish coat that is
available in a variety of textures and colors.
3. Terminology
1.2 The values stated in inch-pound units are to be regarded
3.1 Definitions used in this standard shall be in accordance
as the standard. The metric values given in parentheses are
with Terminology C11.
approximate and are provided for information purposes only.
3.2 Definitions of Terms Specific to This Standard:
1.3 This standard may involve hazardous materials, opera-
tions and equipment. This standard does not purport to address
3.2.1 accessories, n—preformed metal, fiberglass or plastic
all of the safety concerns, if any, associated with its use. It is
members used to form corners, edges, control joints, or
the responsibility of the user of this standard to establish
decorative effects.
appropriate safety and health practices and determine the
3.2.2 back wrapping, n—a deprecated term. See wrap.
applicability of regulatory limitations prior to use.
3.2.3 base coat, n—a material, either factory or field-mixed,
1.4 This international standard was developed in accor-
dance with internationally recognized principles on standard- used to cover the substrate and to encapsulate the reinforcing
ization established in the Decision on Principles for the mesh.
Development of International Standards, Guides and Recom-
3.2.4 cold joint, n—the visible junction in an exterior finish.
mendations issued by the World Trade Organization Technical
3.2.5 cure, v—to develop the ultimate properties of a wet
Barriers to Trade (TBT) Committee.
state material by a chemical process.
2. Referenced Documents
3.2.6 dry, v—to develop the ultimate properties of a wet
2.1 ASTM Standards:
state material solely by evaporation of volatile ingredients.
C11 Terminology Relating to Gypsum and Related Building
3.2.7 durability, n—the capability of a building, assembly,
Materials and Systems
component, product, or construction to maintain serviceability
C1063 Specification for Installation of Lathing and Furring
over not less than a specified time.
to Receive Interior and Exterior Portland Cement-Based
Plaster 3.2.8 embed, v—to encapsulate a non-metallic reinforcing
mesh in either the joint compound or exterior finish.
This practice is under the jurisdiction of ASTM Committee C11 on Gypsum 3.2.9 expansion joint, n—a structural separation between
and Related Building Materials and Systems and is the direct responsibility of
building elements that allows independent movement without
Subcommittee C11.05 on Application of Exterior Insulating and Finish Systems and
damage to the assembly.
Related Products.
Current edition approved April 1, 2017. Published April 2017. Originally
3.2.10 factory mixed, n—a material that is prepared at the
approved in 2002. Last previous edition approved in 2011 as C1516 – 05 (2011).
point of manufacture and is ready to use without the addition
DOI: 10.1520/C1516-05R17.
of other materials, except possibly water to adjust consistency.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
3.2.11 field mix, n—a material that is mixed in the field with
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. other components, water, or both.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1516 − 05 (2017)
3.2.12 finish coat, n—the final wet state material, that 5. Delivery of Materials
provides color or additional texture, applied over the reinforced
5.1 All materials shall be delivered in packages, containers,
base coat.
or bundles with the identification and markings intact.
3.2.13 flash set (quick set), n—the early hardening or
stiffness in the working characteristics of a Portland-cement 6. Inspection
paste, mortar, or concrete, usually with the evolution of
6.1 Inspection of the materials shall be agreed upon between
considerable heat; stiffness cannot be dispelled nor the plastic-
the purchaser and the supplier as part of the purchase agree-
ity regained by further mixing without addition of water; also
ment.
known as “quick set.”
3.2.14 framing member, n—studs, joist, runners (tracks),
7. Rejection
bridging, bracing, and related accessories manufactured or
7.1 Materials that are damaged, frozen or in any way
supplied in wood or hot or cold formed steel.
defective shall not be used. Rejection of materials shall be
3.2.15 initial grab, n—the ability of a wet state material to
promptly reported verbally to the producer and immediately
remain in place initially after it has been applied.
reported in writing. The notice of rejection shall contain a
statement documenting the basis for material rejection.
3.2.16 initial set, n—a time related set caused by the
hydration process.
8. Certification
3.2.17 lamina, n—composite of base coat, reinforcement,
8.1 When specified in the contract documents, the exterior
and finish coat.
finish producer shall furnish a report certifying that the
3.2.18 mechanical fastener, n—corrosion resistant compo-
materials are in conformance with product and material stan-
nent used to attach the substrate to the framing member.
dards and contract documents.
3.2.19 reinforcing mesh, n—a non-metallic component of
8.2 The substrate panels shall be marked as complying with
the DEFS encapsulated in the base coat to strengthen the
the applicable product specification.
system.
3.2.19.1 Discussion—Non-metallic reinforcing mesh is
9. Storage of Materials
available in various weights to achieve different levels of
9.1 All materials shall be kept dry by storage under cover
impact and stress resistance.
and protected from the weather.
3.2.20 pot life, n—the duration of time that the wet state
9.1.1 When outside storage is required, substrate panels
material remains workable after it has been mixed.
shall be stacked flat with care taken to avoid damage to edges,
ends, or surfaces.
3.2.21 primers, n—liquid coatings applied to improve the
adhesion of the DEFS to the substrate.
9.1.2 All other DEFS components shall be stacked off the
ground, supported on a level platform and protected from the
3.2.21.1 Discussion—Primers are sometimes applied to im-
direct sunlight, weather, surface contamination or physical
prove the water resistance of cementitious base coats.
damage in accordance with the DEFS producer’s written
3.2.22 reinforced base coat, n—base coat that has been
instructions.
reinforced with a non-metallic reinforcing mesh.
9.2 Materials shall be protected from exposure to tempera-
3.2.23 substrate, n—surface to which the DEFS is applied.
tures less than 40°F (4°C), unless otherwise specified by the
3.2.24 surface sealer, n—material used to enhance weather
manufacturer.
resistance.
9.3 Portland Cement shall be kept dry until ready for use. It
3.2.25 temper, v—to bring to a workable state by adding
shall be kept off the ground, under cover and away from damp
water.
walls and surfaces.
3.2.26 texture, n—any surface appearance as contrasted to a
10. Environmental Conditions
smooth surface.
10.1 Cold Weather Conditions:
3.2.27 wet edge, n—the leading edge of a continuously
10.1.1 Wet materials shall not be applied when the tempera-
applied wet state material.
ture is less than 40°F (4°C) unless temporary heat and
3.2.28 wet state materials, n—the adhesive, base coat and
enclosures are provided to maintain a minimum temperature of
finish coat components applied in liquid or semi-liquid state.
40°F (4°C) for a minimum period of not less than 24 h before,
during and after application or unless otherwise specified by
4. Significance and Use
the manufacturer.
4.1 This practice provides minimum requirements for the 10.1.2 Materials shall not be applied to a base containing
application of Direct-applied Exterior Finish Systems. The frost. Substrate surface temperature shall be not less than 40°F
requirements for materials, mixtures, and details shall be (4°C) unless otherwise specified by the manufacturer. Mixtures
contained in the project plans and specifications. for application shall not contain any frozen ingredients.
C1516 − 05 (2017)
11. Assessment of Condition of Substrates to Receive 11.7 Substrate Condition—There shall be no visible water.
Direct Exterior and Finish Systems
11.8 If furring or accessories are used, they shall be installed
11.1 The substrate shall be as required by the project plans
in conformance with Specification C1063.
and specifications and as specified by the DEFS producer for
11.8.1 These members shall be properly attached, straight,
the particular system.
and true unless required by the system design.
11.8.2 All accessories shall be free of rust, oil, or other
11.2 The substrate shall be inspected by the applicator and
foreign matter or contaminants, which cause bond failure or
general contractor to ensure that it meets the project plans and
unsightly discoloration.
specifications and the requirements of 11.3 – 11.8.2.
11.3 Sheathing materials shall be inspected to ensure that:
12. Reinforced Base Coat Application
11.3.1 The specified sheathing thickness has been installed
12.1 Inspect the substrate panel surface to ensure that it is
for the stud spacing used.
clean, dry, free of all foreign materials, and damage of any
11.3.2 Fastener type and fastener spacing are as specified.
type. Substrate panel planar irregularities of more than ⁄16 in.
11.3.3 Water-resistant exterior fiber-reinforced gypsum
(1.6 mm) shall be corrected. All panel joints shall be tightly
sheathing panels complying with Specification C1278/
abutted or shall be filled with recommended joint bedding
C1278M, shall be installed in accordance with the sheet
material.
producer’s written installation instructions, which include de-
tails of framing type and spacing, fastener type and spacing,
12.2 Base Coat Preparation—All materials requiring field
and sheet orientation and spacing.
preparation shall be mixed in accordance with the DEFS
11.3.4 Glass mat gypsum sheathing complying with Speci-
producer’s specifications.
fication C1177/C1177M, shall be installed in accordance with
12.3 Base Coat Application—The prepared base coat shall
the sheet producer’s written installation instructions, which
be uniformly spread over the entire surface of the substrate
include details of framing type and spacing, fastener type and
panel.
spacing, and sheet orientation and spacing.
11.3.5 Fiber-cement sheets complying with Specification 12.4 Reinforcing Mesh—The single layer reinforcing mesh,
when specified, shall be fully encapsulated in the field of the
C1186, Type A, shall be installed in accordance with the sheet
producer’s written installation instructions, which include de- wall, at corners, edges, and joints. Trowel from the center to the
edge of the reinforcing mesh to avoid wrinkles. The single
tails of framing type and spacing, fastener type and spacing,
and sheet orientation and spacing. layer reinforcing mesh shall be continuous at all corners.
11.3.6 Fiber-mat reinforced cement sheets complying with
NOTE 1—The recommended method is to apply the base coat in two
Specification C1325, type A, shall be installed in accordance
applications.
with the sheet producer’s written installation instructions,
12.4.1 The surface shall be free of voids, projections, trowel
which include details of framing type and spacing, fastener
marks and other surface irregularities. The base coat thickness
type and spacing, and sheet orientation and spacing.
shall be not less than ⁄16 in. (1.6 mm) dry as measured from the
11.4 Alignment—All substrate surfaces shall be straight and
surface of the substrate panel.
true within ⁄4 in. in 10 ft. (2 mm/m). More stringent require-
12.5 Reinforcing Mesh Overlap—-- All reinforcing mesh
ments by the DEFS producer shall supersede the above stated
edges shall be overlapped not less than 2 ⁄2 in. (64 mm).
requirements.
12.6 Impact Layers—When required, higher impact perfor-
11.5 Suitability for Use—The substrate surface shall be firm,
mance shall be achieved with multiple layers of reinforcing
sound, and undamaged in order to receive the exterior finish.
mesh or by incorporating heavier weight reinforcing mesh. All
11.5.1 Broken, cracked or delaminated substrate boards
areas requiring higher impact performance shall be detailed on
shall be replaced or restored to a condition equal to adjacent
the project plans and specifications. When overlapping of high
undamaged boards.
impact mesh is not required, a complete second layer of
11.6 Cleanliness—The surface of all substrates shall be
reinforcing mesh shall be applied over the layer of high impact
clean and free from any foreign materials such as form release
mesh.
agents, curing compounds, dust, dirt, frost, oil or grease,
12.7 Corners—Reinforcing mesh shall not be lapped within
efflorescence and laitance.
8 in. (204 mm) of any corner.
11.6.1 All substrate panels shall have all loose dirt and dust
removed by cleaning methods appropriate for the job and job
12.8 Wall Penetrations—All edges of the substrate panel
conditions. board at penetrations of the DEFS, such as at windows, doors,
11.6.2 Efflorescence and laitance on substrate panels shall Heating, Ventilation and Air Conditioning (HVAC) sleeves,
be removed prior to exterior finish applicat
...


This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: C1516 − 05 (Reapproved 2011) C1516 − 05 (Reapproved 2017)
Standard Practice for
Application of Direct-Applied Exterior Finish Systems
This standard is issued under the fixed designation C1516; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope*
1.1 This practice covers the minimum requirements and procedures for field application of Direct-applied Exterior Finish
Systems (DEFS). Direct-applied exterior finish systems are coating systems applied over various substrates with non-metallic
1 3
reinforcing mesh, in which the base coat ranges from not less than ⁄16 in. (1.6 mm) to ⁄32 in. (2.4 mm) in dry thickness, depending
on the mass of the reinforcing mesh. This base coat is subsequently covered with a finish coat that is available in a variety of
textures and colors.
1.2 The values stated in inch-pound units are to be regarded as the standard. The metric values given in parentheses are
approximate and are provided for information purposes only.
1.3 This standard may involve hazardous materials, operations and equipment. This standard does not purport to address all
of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate
safety and health practices and determine the applicability of regulatory limitations prior to use.
1.4 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
C11 Terminology Relating to Gypsum and Related Building Materials and Systems
C1063 Specification for Installation of Lathing and Furring to Receive Interior and Exterior Portland Cement-Based Plaster
C1177/C1177M Specification for Glass Mat Gypsum Substrate for Use as Sheathing
C1186 Specification for Flat Fiber-Cement Sheets
C1278/C1278M Specification for Fiber-Reinforced Gypsum Panel
C1325 Specification for Non-Asbestos Fiber-Mat Reinforced Cementitious Backer Units
E1825 Guide for Evaluation of Exterior Building Wall Materials, Products, and Systems
3. Terminology
3.1 Definitions used in this standard shall be in accordance with Terminology C11.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 accessories, n—preformed metal, fiberglass or plastic members used to form corners, edges, control joints, or decorative
effects.
3.2.2 back wrapping, n—a deprecated term. See wrap.
3.2.3 base coat, n—a material, either factory or field-mixed, used to cover the substrate and to encapsulate the reinforcing mesh.
3.2.4 cold joint, n—the visible junction in an exterior finish.
3.2.5 cure, v—to develop the ultimate properties of a wet state material by a chemical process.
3.2.6 dry, v—to develop the ultimate properties of a wet state material solely by evaporation of volatile ingredients.
This practice is under the jurisdiction of ASTM Committee C11 on Gypsum and Related Building Materials and Systems and is the direct responsibility of Subcommittee
C11.05 on Application of Exterior Insulating and Finish Systems and Related Products.
Current edition approved Dec. 1, 2011April 1, 2017. Published June 2011April 2017. Originally approved in 2002. Last previous edition approved in 20052011 as
C1516 – 05.C1516 – 05 (2011). DOI: 10.1520/C1516-05R11.10.1520/C1516-05R17.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1516 − 05 (2017)
3.2.7 durability, n—the capability of a building, assembly, component, product, or construction to maintain serviceability over
not less than a specified time.
3.2.8 embed, v—to encapsulate a non-metallic reinforcing mesh in either the joint compound or exterior finish.
3.2.9 expansion joint, n—a structural separation between building elements that allows independent movement without damage
to the assembly.
3.2.10 factory mixed, n—a material that is prepared at the point of manufacture and is ready to use without the addition of other
materials, except possibly water to adjust consistency.
3.2.11 field mix, n—a material that is mixed in the field with other components and/or water.components, water, or both.
3.2.12 finish coat, n—the final wet state material, that provides color or additional texture, applied over the reinforced base coat.
3.2.13 flash set (quick set), n—the early hardening or stiffness in the working characteristics of a Portland-cement paste, mortar,
or concrete, usually with the evolution of considerable heat; stiffness cannot be dispelled nor the plasticity regained by further
mixing without addition of water; also known as “quick set.”
3.2.14 framing member, n—studs, joist, runners (tracks), bridging, bracing, and related accessories manufactured or supplied in
wood or hot or cold formed steel.
3.2.15 initial grab, n—the ability of a wet state material to remain in place initially after it has been applied.
3.2.16 initial set, n—a time related set caused by the hydration process.
3.2.17 lamina, n—composite of base coat, reinforcement, and finish coat.
3.2.18 mechanical fastener, n—corrosion resistant component used to attach the substrate to the framing member.
3.2.19 reinforcing mesh, n—a non-metallic component of the DEFS encapsulated in the base coat to strengthen the system.
3.2.19.1 Discussion—
Non-metallic reinforcing mesh is available in various weights to achieve different levels of impact and stress resistance.
3.2.20 pot life, n—the duration of time that the wet state material remains workable after it has been mixed.
3.2.21 primers, n—liquid coatings applied to improve the adhesion of the DEFS to the substrate.
3.2.21.1 Discussion—
Primers are sometimes applied to improve the water resistance of cementitious base coats.
3.2.22 reinforced base coat, n—base coat that has been reinforced with a non-metallic reinforcing mesh.
3.2.23 substrate, n—surface to which the DEFS is applied.
3.2.24 surface sealer, n—material used to enhance weather resistance.
3.2.25 temper, v—to bring to a workable state by adding water.
3.2.26 texture, n—any surface appearance as contrasted to a smooth surface.
3.2.27 wet edge, n—the leading edge of a continuously applied wet state material.
3.2.28 wet state materials, n—the adhesive, base coat and finish coat components applied in liquid or semi-liquid state.
4. Significance and Use
4.1 This practice provides minimum requirements for the application of Direct-applied Exterior Finish Systems. The
requirements for materials, mixtures, and details shall be contained in the project plans and specifications.
5. Delivery of Materials
5.1 All materials shall be delivered in packages, containers, or bundles with the identification and markings intact.
6. Inspection
6.1 Inspection of the materials shall be agreed upon between the purchaser and the supplier as part of the purchase agreement.
7. Rejection
7.1 Materials that are damaged, frozen or in any way defective shall not be used. Rejection of materials shall be promptly
reported verbally to the producer and immediately reported in writing. The notice of rejection shall contain a statement
documenting the basis for material rejection.
C1516 − 05 (2017)
8. Certification
8.1 When specified in the contract documents, the exterior finish producer shall furnish a report certifying that the materials are
in conformance with product and material standards and contract documents.
8.2 The substrate panels shall be marked as complying with the applicable product specification.
9. Storage of Materials
9.1 All materials shall be kept dry by storage under cover and protected from the weather.
9.1.1 When outside storage is required, substrate panels shall be stacked flat with care taken to avoid damage to edges, ends,
or surfaces.
9.1.2 All other DEFS components shall be stacked off the ground, supported on a level platform and protected from the direct
sunlight, weather, surface contamination or physical damage in accordance with the DEFS producer’s written instructions.
9.2 Materials shall be protected from exposure to temperatures less than 40 °F (4 °C), 40°F (4°C), unless otherwise specified
by the manufacturer.
9.3 Portland Cement shall be kept dry until ready for use. It shall be kept off the ground, under cover and away from damp walls
and surfaces.
10. Environmental Conditions
10.1 Cold Weather Conditions:
10.1.1 Wet materials shall not be applied when the temperature is less than 40 °F (4 °C) 40°F (4°C) unless temporary heat and
enclosures are provided to maintain a minimum temperature of 40 °F (4 °C) 40°F (4°C) for a minimum period of not less than
24 h before, during and after application or unless otherwise specified by the manufacturer.
10.1.2 Materials shall not be applied to a base containing frost. Substrate surface temperature shall be not less than 40 °F (4
°C) 40°F (4°C) unless otherwise specified by the manufacturer. Mixtures for application shall not contain any frozen ingredients.
11. Assessment of Condition of Substrates to Receive Direct Exterior and Finish Systems
11.1 The substrate shall be as required by the project plans and specifications and as specified by the DEFS producer for the
particular system.
11.2 The substrate shall be inspected by the applicator and general contractor to ensure that it meets the project plans and
specifications and the requirements of 11.3 – 11.8.2.
11.3 Sheathing materials shall be inspected to ensure that:
11.3.1 The specified sheathing thickness has been installed for the stud spacing used.
11.3.2 Fastener type and fastener spacing are as specified.
11.3.3 Water-resistant exterior fiber-reinforced gypsum sheathing panels complying with Specification C1278/C1278M, shall be
installed in accordance with the sheet producer’s written installation instructions, which include details of framing type and
spacing, fastener type and spacing, and sheet orientation and spacing.
11.3.4 Glass mat gypsum sheathing complying with Specification C1177/C1177M, shall be installed in accordance with the
sheet producer’s written installation instructions, which include details of framing type and spacing, fastener type and spacing, and
sheet orientation and spacing.
11.3.5 Fiber-cement sheets complying with Specification C1186, Type A, shall be installed in accordance with the sheet
producer’s written installation instructions, which include details of framing type and spacing, fastener type and spacing, and sheet
orientation and spacing.
11.3.6 Fiber-mat reinforced cement sheets complying with Specification C1325, type A, shall be installed in accordance with
the sheet producer’s written installation instructions, which include details of framing type and spacing, fastener type and spacing,
and sheet orientation and spacing.
11.4 Alignment—All substrate surfaces shall be straight and true within ⁄4 in. in 10 ft. (2 mm/m). More stringent requirements
by the DEFS producer shall supersede the above stated requirements.
11.5 Suitability for Use—The substrate surface shall be firm, sound, and undamaged in order to receive the exterior finish.
11.5.1 Broken, cracked or delaminated substrate boards shall be replaced or restored to a condition equal to adjacent undamaged
boards.
11.6 Cleanliness—The surface of all substrates shall be clean and free from any foreign materials such as form release agents,
curing compounds, dust, dirt, frost, oil or grease, efflorescence and laitance.
11.6.1 All substrate panels shall have all loose dirt and dust removed by cleaning methods appropriate for the job and job
conditions.
C1516 − 05 (2017)
11.6.2 Efflorescence and laitance on substrate panels shall be removed prior to exterior finish application. Heavy deposits shall
be removed using hand or power impact tools followed by washing with an appropriate cleaner. Light deposits shall be removed
by washing with an appropriate cleaner. All loose particles and cleaner residue shall be removed by washing with clean, potable
water. The surface shall be allowed to dry.
11.7 Substrate Condition—There shall be no visible water.
11.8 If furring or accessories are used, they shall be installed in conformance with Specification C1063.
11.8.1 These members shall be properly attached, straight, and true unless required by the system design.
11.8.2 All accessories shall be free of rust, oil, or other foreign matter or contaminants, which cause bond failure or unsightly
discoloration.
12. Reinforced Base Coat Application
12.1 Inspect the substrate panel surface to ensure that it is clean, dry, free of all foreign materials, and damage of any type.
Substrate panel planar irregularities of more than ⁄16 in. (1.6 mm) shall be corrected. All panel joints shall be tightly abutted or
shall be filled with recommended joint bedding material.
12.2 Base Coat Preparation—All materials requiring field preparation shall be mixed in accordance with the DEFS producer’s
specifications.
12.3 Base Coat Application—The prepared base coat shall be uniformly spread over the entire surface of the substrate panel.
12.4 Reinforcing Mesh—The single layer reinforcing mesh, when specified, shall be fully encapsulated in the field of the wall,
at corners, edges, and joints. Trowel from the center to the edge of the reinforcing mesh to avoid wrinkles. The single layer
reinforcing mesh shall be continuous at all corners.
NOTE 1—The recommended method is to apply the base coat in two applications.
12.4.1 The surface shall be free of voids, projections, trowel marks and other surface irregularities. The base coat thickness shall
be not less than ⁄16 in. (1.6 mm) dry as measured from the surface of the substrate panel.
12.5 Reinforcing Mesh Overlap—-- All reinforcing m
...

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