ASTM C926-15

Standard Specification for Application of Portland Cement-Based Plaster

ABSTRACT
This specification covers the standard requirements for the application of full thickness Portland cement-based plaster for exterior (stucco) and interior work. It also sets forth tables for proportioning of various plaster mixes and plaster thickness. The materials used shall consist of the following: cement which shall be a Portland cement, air-entraining Portland cement, masonry cement, blended hydraulic cement, air-entraining blended hydraulic cement, or plastic cement; Type S hydrated lime; aggregates such as perlite and sand for base and job-mixed finish coats; water to be used in mixing; admixtures; and fibers. Surfaces of solid bases such as masonry, stone, cast-in-place or precast concrete shall be prepared either by sandblasting, wire brushing, acid etching, chipping, or a combination thereof. Details on curing to resist cracking; materials protection and storage; environmental conditions; and application of plaster, finish-coat, and fog-coat, which shall be done by hand or machine up to the specified nominal thickness on metal and solid plaster bases are discussed.
SCOPE
1.1 This specification covers the requirements for the application of full thickness portland cement-based plaster for exterior (stucco) and interior work.  
1.2 This specification sets forth tables for proportioning of various plaster mixes and plaster thickness.  
Note 1: General information will be found in Annex A1. Design considerations will be found in Annex A2.  
1.3 The values stated in inch-pound units are to be regarded as the standard. The SI (metric) values given in parentheses are approximate and are provided for information purposes only.  
1.4 The text of this specification references notes and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the specification.  
1.5 Details of construction for a specific assembly to achieve the required fire resistance shall be obtained from reports of fire-resistance tests, engineering evaluations, or listings from recognized fire testing laboratories.

General Information

• Status: Historical
• Publication Date: 31-Jan-2015
• ICS: 91.100.10 - Cement. Gypsum. Lime. Mortar
• Technical Committee: C11 - Gypsum and Related Building Materials and Systems
• Drafting Committee: C11.03 - Specifications for the Application of Gypsum and Other Products in Assemblies

Relations

• Replaces: ASTM C926-14a - Standard Specification for Application of Portland Cement-Based Plaster
• Effective Date: 01-Feb-2015
• Replaced By: ASTM C926-15a - Standard Specification for Application of Portland Cement-Based Plaster
• Effective Date: 01-Jun-2015
• Referred By: ASTM C1861-23 - Standard Specification for Lathing and Furring Accessories, and Fasteners, for Interior and Exterior Portland Cement-Based Plaster
• Effective Date: 01-Feb-2015
• Referred By: ASTM C1787-23 - Standard Specification for Installation of Non Metallic Plaster Bases (Lath) Used with Portland Cement Based Plaster in Vertical Wall Applications
• Effective Date: 01-Feb-2015
• Referred By: ASTM C1328/C1328M-23 - Standard Specification for Plastic (Stucco) Cement
• Effective Date: 01-Feb-2015
• Referred By: ASTM C1788-20 - Standard Specification for Non Metallic Plaster Bases (Lath) Used With Portland Cement Based Plaster in Vertical Wall Applications
• Effective Date: 01-Feb-2015
• Referred By: ASTM E2266-22 - Standard Guide for Design and Construction of Low-Rise Frame Building Wall Systems to Resist Water Intrusion
• Effective Date: 01-Feb-2015
• Referred By: ASTM C1764-20 - Standard Test Methods for Non Metallic Plaster Bases (Lath) Used With Portland Cement Based Plaster in Vertical Wall Applications
• Effective Date: 01-Feb-2015
• Referred By: ASTM C1324-20a - Standard Test Method for Examination and Analysis of Hardened Masonry Mortar
• Effective Date: 01-Feb-2015
• Referred By: ASTM C1780-23a - Standard Practice for Installation Methods for Cement-based Adhered Masonry Veneer
• Effective Date: 01-Feb-2015
• Referred By: ASTM C1063-23 - Standard Specification for Installation of Lathing and Furring to Receive Interior and Exterior Portland Cement-Based Plaster
• Effective Date: 01-Feb-2015

Standards Content (Sample)

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:C926 −15
StandardSpecification for
1
Application of Portland Cement-Based Plaster
This standard is issued under the fixed designation C926; 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* C207 Specification for Hydrated Lime for Masonry Pur-
poses
1.1 This specification covers the requirements for the appli-
C219 Terminology Relating to Hydraulic Cement
cation of full thickness portland cement-based plaster for
C260 Specification for Air-Entraining Admixtures for Con-
exterior (stucco) and interior work.
crete
1.2 This specification sets forth tables for proportioning of
C595 Specification for Blended Hydraulic Cements
various plaster mixes and plaster thickness.
C631 Specification for Bonding Compounds for Interior
Gypsum Plastering
NOTE 1—General information will be found in Annex A1. Design
considerations will be found in Annex A2.
C897 Specification for Aggregate for Job-Mixed Portland
Cement-Based Plasters
1.3 The values stated in inch-pound units are to be regarded
C932 Specification for Surface-Applied Bonding Com-
as the standard.The SI (metric) values given in parentheses are
pounds for Exterior Plastering
approximate and are provided for information purposes only.
C1063 Specification for Installation of Lathing and Furring
1.4 The text of this specification references notes and
to Receive Interior and Exterior Portland Cement-Based
footnotes that provide explanatory material. These notes and
Plaster
footnotes (excluding those in tables and figures) shall not be
C1116 Specification for Fiber-Reinforced Concrete and
considered as requirements of the specification.
Shotcrete
1.5 Details of construction for a specific assembly to
C1328 Specification for Plastic (Stucco) Cement
achieve the required fire resistance shall be obtained from
E90 Test Method for Laboratory Measurement of Airborne
reports of fire-resistance tests, engineering evaluations, or
Sound Transmission Loss of Building Partitions and
listings from recognized fire testing laboratories.
Elements
E119 Test Methods for Fire Tests of Building Construction
2. Referenced Documents
and Materials
2
E492 Test Method for Laboratory Measurement of Impact
2.1 ASTM Standards:
Sound Transmission Through Floor-Ceiling Assemblies
C11 Terminology Relating to Gypsum and Related Building
Using the Tapping Machine
Materials and Systems
2.2 ANSI Standard:
C25 Test Methods for Chemical Analysis of Limestone,
3
A108.1 Specification for Installation of Ceramic Tile
Quicklime, and Hydrated Lime
C35 Specification for Inorganic Aggregates for Use in Gyp-
3. Terminology
sum Plaster
3.1 Terms shall be defined as in Terminologies C11 and
C91 Specification for Masonry Cement
C219, except as modified herein.
C150 Specification for Portland Cement
C206 Specification for Finishing Hydrated Lime
3.2 Definitions of Terms Specific to This Standard:
3.2.1 accelerator, n—an admixture that will shorten the
setting time of plaster.
1
This specification is under the jurisdiction of ASTM Committee C11 on
3.2.2 admixture, n—a material other than water, aggregate,
GypsumandRelatedBuildingMaterialsandSystemsandisthedirectresponsibility
or basic cementitious material added to the batch before or
ofSubcommitteeC11.03onSpecificationsfortheApplicationofGypsumandOther
during job mixing.
Products in Assemblies.
Current edition approved Feb. 1, 2015. Published February 2015. Originally
3.2.3 acid etching, n—the cleansing and controlled erosion
approved in 1981. Last previous edition approved in 2014 as C926 – 14a. DOI:
of a solid surface, using an acid wash.
10.1520/C0926-15.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
3
Standards volume information, refer to the standard’s Document Summary page on Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
the ASTM website. 4th Floor, New York, NY 10036.
*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
1

---------------------- Page: 1 ----------------------
C926−15
3.2.4 air entrainment, n—the use of an air-entraining ad- 3.2.12 curing, v—the act or processes of producing a mois-
mixture or air-entraining cementitious material in a plaster mix ture environment favorable to cement hydration, resulting in
to yield a controlled quantity of minute (typically between 10 the setting or hardening of the plaster.
and 1000 µm in diameter) disconnected air bubbles in the
3.2.13 drainage wall,
...

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: C926 − 14a C926 − 15
Standard Specification for
1
Application of Portland Cement-Based Plaster
This standard is issued under the fixed designation C926; 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 specification covers the requirements for the application of full thickness portland cement-based plaster for exterior
(stucco) and interior work.
1.2 This specification sets forth tables for proportioning of various plaster mixes and plaster thickness.
NOTE 1—General information will be found in Annex A1. Design considerations will be found in Annex A2.
1.3 The values stated in inch-pound units are to be regarded as the standard. The SI (metric) values given in parentheses are
approximate and are provided for information purposes only.
1.4 The text of this specification references notes and footnotes that provide explanatory material. These notes and footnotes
(excluding those in tables and figures) shall not be considered as requirements of the specification.
1.5 Details of construction for a specific assembly to achieve the required fire resistance shall be obtained from reports of
fire-resistance tests, engineering evaluations, or listings from recognized fire testing laboratories.
2. Referenced Documents
2
2.1 ASTM Standards:
C11 Terminology Relating to Gypsum and Related Building Materials and Systems
C25 Test Methods for Chemical Analysis of Limestone, Quicklime, and Hydrated Lime
C35 Specification for Inorganic Aggregates for Use in Gypsum Plaster
C91 Specification for Masonry Cement
C150 Specification for Portland Cement
C206 Specification for Finishing Hydrated Lime
C207 Specification for Hydrated Lime for Masonry Purposes
C219 Terminology Relating to Hydraulic Cement
C260 Specification for Air-Entraining Admixtures for Concrete
C595 Specification for Blended Hydraulic Cements
C631 Specification for Bonding Compounds for Interior Gypsum Plastering
C897 Specification for Aggregate for Job-Mixed Portland Cement-Based Plasters
C932 Specification for Surface-Applied Bonding Compounds for Exterior Plastering
C1063 Specification for Installation of Lathing and Furring to Receive Interior and Exterior Portland Cement-Based Plaster
C1116 Specification for Fiber-Reinforced Concrete and Shotcrete
C1328 Specification for Plastic (Stucco) Cement
E90 Test Method for Laboratory Measurement of Airborne Sound Transmission Loss of Building Partitions and Elements
E119 Test Methods for Fire Tests of Building Construction and Materials
E492 Test Method for Laboratory Measurement of Impact Sound Transmission Through Floor-Ceiling Assemblies Using the
Tapping Machine
2.2 ANSI Standard:
3
A108.1 Specification for Installation of Ceramic Tile
1
This specification is under the jurisdiction of ASTM Committee C11 on Gypsum and Related Building Materials and Systems and is the direct responsibility of
Subcommittee C11.03 on Specifications for the Application of Gypsum and Other Products in Assemblies.
Current edition approved April 15, 2014Feb. 1, 2015. Published June 2014February 2015. Originally approved in 1981. Last previous edition approved in 2014 as
C926C926 – 14a.–14. DOI: 10.1520/C0926-14A.10.1520/C0926-15.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
3
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036.
*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
1

---------------------- Page: 1 ----------------------
C926 − 15
3. Terminology
3.1 Terms shall be defined as in Terminologies C11 and C219, except as modified herein.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 accelerator—accelerator, n—an admixture that will shorten the setting time of plaster.
3.2.2 admixture—admixture, n—a material other than water, aggregate, or basic cementitious material added to the batch before
or during job mixing.
3.2.3 acid etching—etching, n—the cleansing and controlled erosion of a solid surface, using an acid wash.
3.2.4 air entrainment—entrainment, n—
...