Standard Specification for Mortars for the Repair of Historic Masonry

1.1 This specification covers mortar for the repair of masonry constructed with methods and materials that pre-date the origination of current standards of construction. The mortar may be used for non-structural purposes such as repointing of the masonry, or for structural purposes such as, but not restricted to, re-construction or repair of mortar joints that contribute to the structural integrity of the masonry.

1.2 Masonry includes the following units laid in mortar: (1) cast stone, (2) clay brick and tile, (3) concrete masonry, (4) natural stone, (5) terra cotta, and (6) calcium silicate.

1.3 This specification may be used to pre-qualify mortar for a project.

1.4 Mortars tested using this specification are laboratory-prepared mortars and do not represent in-place, site mortars.

1.5 This specification provides a basis for the design of an appropriate mortar formulation based upon performance, material and aesthetic requirements. Use of this specification requires a thorough understanding of the function, maintenance, and repair requirements for the preservation and continued performance of the masonry assembly in the context of the assembly’s structure, water management, and long-term performance.

1.6 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.7 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.8 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.