ASTM E2260-03(2012)e1

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Designation: E2260 − 03 (Reapproved 2012)
Standard Guide for
Repointing (Tuckpointing) Historic Masonry
This standard is issued under the fixed designation E2260; 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.
ε NOTE—Section 2.2 was editorially corrected in November 2013.
1. Scope 2. Referenced Documents
2.1 ASTM Standards:
1.1 This guide applies only to existing historic masonry
C67 Test Methods for Sampling and Testing Brick and
construction. For purposes of this guide historic masonry is
Structural Clay Tile
intended to refer to buildings that have significant historic,
C140 Test Methods for Sampling and Testing Concrete
architectural, cultural or social meaning and are constructed of
Masonry Units and Related Units
masonry materials. Similar techniques and evaluation should
C170 Test Method for Compressive Strength of Dimension
be employed for non-historic masonry, but are not addressed in
Stone
this guide.
C780 Test Method for Preconstruction and Construction
1.2 This guide outlines procedures for repointing historic
Evaluation of Mortars for Plain and Reinforced Unit
masonry and is intended to provide guidelines for the user to
Masonry
establish project-specific requirements for repointing of his-
C1324 Test Method for Examination and Analysis of Hard-
toric masonry.
ened Masonry Mortar
1.3 This guide only pertains to masonry units: brick, terra
E1857 Guide for Selection of Cleaning Techniques for
cotta, stone, cast stone, and concrete brick laid in mortar, and
Masonry, Concrete, and Stucco Surfaces
may or may not be appropriate for other masonry units.
C270 Specification for Mortar for Unit Masonry
C1072 Test Methods for Measurement of Masonry Flexural
1.4 This guide addresses repointing (tuckpointing) as de-
Bond Strength
fined in 3.1.3.
E631 Terminology of Building Constructions
1.5 When considering repointing, especially on masonry of
2.2 Other Referenced Documents:
artistic, architectural, cultural, or historical significance, guid-
ACI 530.1/ASCE 6/TMS 602 Specifications for Masonry
ance from a specialist experienced in historic masonry and
Structures
repointing should be sought.
BIA Technical Note 7F Moisture Resistance of Brick Ma-
1.6 This guide does not address pointing styles or profiles
sonry Maintenance, reissued October 1998
used on masonry or the methods of producing them.
BIA Technical Note 1 All-Weather Construction, revised
March 1992
1.7 Additional repairs that may impact the structural integ-
Secretary of the Interior’s Standards for the Treatment of
rity of the masonry may necessitate that a structural stability
Historic Properties, revised 1995
analysis be completed prior to the execution of any work.
London, M., Masonry: How to Care for Old and Historic
1.8 Following this guide may involve hazardous materials,
Brick and Stone,ThePreservationPress,Washington,DC,
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 deter-
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
mine the applicability of regulatory requirements prior to use.
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.
Available fromAmerican Concrete Institute (ACI), P.O. Box 9094, Farmington
This guide is under the jurisdiction of ASTM Committee E06 on Performance Hills, MI 48333-9094, http://www.concrete.org.
of Buildings and is the direct responsibility of Subcommittee E06.24 on Building Available from the Brick Industry Association (BIA), 1850 Centennial Park
Preservation and Rehabilitation Technology. Drive, Suite 301, Reston, VA 20191, http://www.bia.org.
Current edition approved Jan. 1, 2012. Published January 2012. Originally Available from U.S. Department of the Interior, National Park Service,
published in 2003. Last previous edition approved in 2003 as E2260 – 03. DOI: Preservation Assistance Division, 1849 C Street, N.W., Washington DC 20240,
10.1520/E2260-03R12E01. http://www.doi.gov.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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E2260 − 03 (2012)
McKee, H. J., “Introduction to Early American Masonry: 4. Significance and Use
Stone, Brick, Mortar, and Plaster,” The National Trust,
4.1 Repointing masonry improves weather resistance, re-
Washington, DC, 1973.
duces water penetration, maintains structural and visual
“Preparation and Use of Lime Mortars: An Introduction to
integrity, and prolongs the life of the building by allowing a
the Principles of Using Lime Mortars,” Historic Scotland,
mortar joint to shed water and avoid the accumulation and
Edinburgh, Scotland, 1998
penetration of rainwater between mortar and masonry units.
Oats, J. A. H., Lime and Limestone—Chemistry and
4.2 This guide provides for the selection of the most
Technology, Production and Uses, Wiley-VCH, New
effective methods appropriate for repointing masonry based
York, 1998
upon the following parameters:
Mack, R. C., and Speweik, J. P., Preservation Brief #2,
“Repointing Mortar Joints in Historic Masonry 4.2.1 Determination of joints to be repointed.
Buildings,”NationalParkService,U.S.Departmentofthe 4.2.2 Evaluation of in-situ masonry.
Interior, Washington, DC, 1998
4.2.3 Evaluation of techniques for removal of mortar.
Weaver, M., Conserving Buildings: A Guide to Techniques
4.2.4 Determination of appropriate repointing mortar.
and Materials, John Wiley & Sons, Inc., New York, NY,
4.2.5 Selection of repointing mortar.
4.2.6 Establishing the method of execution of the work.
IS 240 “Trowel Tips: Tuckpointing,” Portland Cement
4.2.7 Visual inspection of the work.
Association, Skokie, IL, 1992
5. Determination of Joints to be Repointed
3. Terminology
5.1 In many cases, not all joints in the masonry need to be
3.1 Definitions of Terms Specific to This Standard:
repointed. It may be prudent to repoint only portions of the
3.1.1 in-situ mortar—mortar existing in the masonry con-
masonry or not to repoint at all (see Secretary of the Interior’s
structionwhichincludestheoriginalsettingorpointingmortar,
Standards).
or both and subsequently installed setting or repointing mortar.
5.2 Closely examine mortar joints to determine which joints
3.1.2 masonry—for this guide, masonry is defined as brick,
require repointing. Defective joints require repointing. Defec-
terra cotta, stone, cast stone and concrete brick which is set in
tive joints include joints that are cracked, deteriorated, eroded,
mortar.
contain voids, or are poorly bonded to masonry units. Cleaning
3.1.3 mortar removal techniques:
of selected areas of the masonry to help identify areas needing
3.1.3.1 chiseling—use of a hammer and chisel to remove
repointing should only be done when necessary for evaluation
mortar.
(see Guide E1857 and Secretary of the Interior’s Standards).
3.1.3.2 power chiseling—hand-held short stroke pneumatic
5.3 If the masonry was previously repointed with a mortar
carving tool with a round shank chisel blade with no retainer to
which has a higher compressive strength than the adjoining
remove mortar.
masonry, the previously installed repointing mortar should be
3.1.3.3 power router—hand-held motor driven device using
removed and the joints should be repointed.
a diamond embedded router bit or other suitable abrasive bit to
removal mortar.
5.4 Visually inappropriate, previously installed repointing
3.1.3.4 raking—use of a hand tool to remove mortar.
mortar should be replaced. If color, texture, and joint profiles
3.1.3.5 sawing/grinding—use of a diamond-tipped, silicon
do not match the existing historic mortar joints, the joints
carbide-tipped, or other suitable abrasive blade to remove
should be removed and repointed.
mortar.
5.5 In some cases, sealants or other inappropriate materials
3.1.4 original mortar—mortar used in the original construc-
mayhavebeenusedinjointsofmasonryunits.Thesematerials
tionofthemasonrywallwhichmaybeonlytheoriginalsetting
should be removed and the joints repointed.
mortar or may also include original pointing mortar.
3.1.5 original pointing mortar—the mortar placed into a
6. Evaluation of In-Situ Masonry
joint (exposed outer edge) from which fresh setting mortar was
6.1 If shoring of the masonry is required, the necessary
raked out during original construction of the masonry wall.
materials and methods should be identified.
3.1.6 point—placing mortar into a properly prepared joint.
6.2 Evaluate In-Situ Mortar:
3.1.7 repointing—the process of removal of defective mor-
6.2.1 In-situ mortar may include previously installed re-
tar from between masonry units and placement of fresh mortar.
pointing mortar, and each masonry structure may be comprised
3.1.8 repointing mortar—the new mortar to be selected by
of different mortars of varying ages and materials. Identifica-
the user of this guide.
tion of the original mortar is an integral part of the process of
3.1.9 specialist—architect, conservator, engineer or other
selecting an appropriate repointing mortar.
professional with appropriate applicable experience, hereinaf-
6.2.2 The color and texture of the in-situ mortar to be
ter referred to as the specialist.
matched should be evaluated by visual and laboratory means.
3.1.10 tuckpointing—for purposes of this guide, synony- Original color can be reasonably determined by visual exami-
mous with repointing. nation of a freshly broken surface of a mortar sample.
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E2260 − 03 (2012)
6.3 Evaluate Masonry Materials—The physical properties texture,andfinishpriortotherepointingwork.Samplesshould
of masonry units should be assessed to ensure compatibility be compared after the mortar has sufficiently hardened for
with the repointing mortar. handling and has attained its final color.
6.3.1 When required, the physical properties of the masonry
8.2 Samples of the proposed repointing mortar should be
should be tested in accordance with Test Methods C67, C140,
prepared prior to the repointing work to determine mortar
and C170, respectively.
properties. Mortar properties should be evaluated in accor-
6.3.2 For some repointing projects, sampling and testing of
dance with the sampling and testing procedures inTest Method
masonry units and materials is not permitted or necessary. In
C780.
such cases, a qualitative assessment of the physical properties
8.3 Test areas should be used to evaluate mortar removal
of materials can suffice. Such qualitative assessment should
techniques, mortar formulation, pointing techniques, final
include identification of the type of masonry materials and a
cleaning and appearance. Test areas should be approved prior
visual inspection of the condition of the materials. Literature
to proceeding with the work. Test areas should have the
from the appropriate period can be reviewed for an indication
following characteristics:
of properties of the materials. When available, the original
8.3.1 Test areas should include materials and conditions
material specifications and relevant maintenance and repair
representative of surfaces to be repointed.
work for the building should be reviewed.
8.3.2 Test areas should permit evaluation of the effects of
7. Evaluation of Techniques for Removal of Mortar
the repointing work on materials, surfaces, and surroundings.
8.3.3 Test areas should permit visual inspection and com-
7.1 In determining the method of mortar removal, a stan-
parison to adjacent masonry surfaces that have not been
dard should be established for joint preparation that limits the
repointed. Inspection should be performed under similar light-
damage to masonry units and provides a proper substrate for
ing and exposure conditions.
bonding of new mortar. Prior to beginning the work, potential
techniques for mortar removal should be evaluated.
9. Selection of Repointing Mortar
7.2 Mortarremovalproceduresshouldattempttoremoveall
9.1 The repointing mortar should be selected based on the
mortar from joints to the specified depth and to provide a
purpose of repointing and with consideration given to its
substrate to which the repair mortar can properly adhere.
historic proportions and compatibility with masonry materials.
7.3 Mortar can be removed using various procedures. Tech-
Formulationoftherepointingmortarshouldnotbebasedonan
niques including raking, chiseling, routing, and grinding, are
inappropriate, previously installed pointing mortar.
listed and described in Section 3. Combinations of these
9.2 The selected repointing mortar should match the origi-
techniques can also be used.
nal mortar (if originally used) or exposed mortar unless it is
7.4 On historic masonry, it is recommended that the most
determined that either is inappropriate for use.
effective and least damaging technique be used as the method
9.3 Theselectedrepointingmortarshouldbetheappropriate
of mortar removal.
color and texture as determined by the user of this guide and
NOTE 1—Hand raking alone as a technique should only be used if it can
exhibit the durability and performance desired. See 8.1.
be determined that hand raking can be performed without causing damage
to masonry. If hand raking is determined to damage the masonry units,
9.4 The visual matching of in-situ mortar with the repoint-
other techniques of mortar removal shall be considered.
ing mortar may be desired but can be difficult to achieve. An
7.5 Although some damage may be inevitable, careful joint
acceptable match can require analysis of the in-situ mortar
preparation can help limit damage to masonry units.
materials, trial mix proportions using new mortar materials,
and variations in placement and tooling of the repointing
7.6 It is the responsibility of the user of this guide to
mortar.Ifitisdesiredtomatchtheappearanceoftherepointing
evaluate the advantages and disadvantages of the various
mortar to the in-situ mortar, the unsoiled color, determined by
removal techniques as they relate to type and condition of the
examining the interior surface of the mortar, should be
masonry to be repointed.
matched. Proposed repointing mortars should be installed and
7.7 The use of power tools is not recommended for joints of
evaluated in test areas, refer to Section 8.
less than 3 mm, where the geometry of the joint limits access,
9.5 The composition of the repointing
...