Any masonry construction project, be it large or small, needs to be designed and constructed in a manner so that the final product is safe and aesthetically acceptable. This is accomplished by exceeding the minimum standards set forth in project documents and building code, but where is the code information? When looking at the International Building Code, there is little information on the minimum requirements for constructing masonry, but there is a reference to a document called TMS 402/602. First some history.

When looking back on historic codes, masonry provisions were completely contained within the Code, whether it be the Uniform Building Code, the BOCA National Building Code or the Southern Standard Building Code (SBC). Under the old system, building officials had complete control of masonry design and construction requirements.

Reflecting back to the 1970’s and using the Concrete Code, ACI 318, Building Code and Commentary for Structural Concrete as precedent, a masonry standard was developed. Originally titled Building Code Requirements (and Specification) for Concrete Masonry Structures (ACI 531/ACI 531.1), the standard expanded in 1988 to include clay masonry and rebranded as Building Code Requirements and Specification for Masonry Structures (ACI 530/ASCE 5 and ACI 530.1/ASCE 6). Unlike the code controlled by building officials, the documents were developed and maintained by industry with a committee balance of individuals classified as producers, users and genera interest.

In 1992, your industry representative in the code arena, The Masonry Society (TMS), was added as a co-sponsor of the ACI 530 document with the understanding that ultimately, TMS would become the sole producer of the masonry standard. Fast forward to 2013 where an agreement was reached to release the masonry standard exclusively to TMS so that in 2016, the document has a new designation, TMS 402/602. This is a big deal since the masonry industry now has the voice for masonry design and construction. So, what does the 2022 Committee and workload look like?

There were 101 completed applications and all are contributing to the Main Committee or one or more Subcommittees in some capacity. The Main Committee, which is the final vote with respect to code changes, contains 45 voting members. Contractors have a voice of about 25% on the Main Committee represented by active contractors, material producers and contractor associations. The balance of the committee is made up of Users, or designers, and General Interest, or typically academia representation. The subcommittee structure was changed slightly for the 2022 committee so that each chapter or section of the code has only one subcommittee responsible for that chapter or section. Subcommittees may, however, have responsibility for more than one chapter, such as the Construction Requirements Subcommittee.

The Construction Requirements Subcommittee, chaired by Jonathon Merk of Forrest & Associate, has 15 voting members and 11 corresponding members. Of the 15 voting members, 6 are directly from the masonry industry and 6 are masonry-friendly designers which speaks well of the subcommittee representation. This subcommittee is responsible for the entire Specification which parallels the three-part format of a typical CSI project specification format, as well as Code Chapter 3, Quality and Construction. Most of the members have extensive field experience which will make changes realistic rather than theoretical.

The responsibility of the Construction Requirements Subcommittee is significant. The following chart shows how the Code and Specification is organized providing a sense of issues important to the contractor:

Building Code Requirements and Specifications for Masonry Structures (TMS 402/602)

The first order of business for the 2022 Committee is to address Public and Technical comments held over from the last two code cycles. Some, but not all, comments will result in code changes. Fortunately, the Construction Requirements Subcommittee was tasked with only 2 of the 78 comments received. Once these two comments are addressed, the Construction Requirements Subcommittee will begin to consider new issues.

The Code and Specification are very dynamic documents with constantly changing provisions. For example, a major change introduced in the 2016 cycle is a qualification requirement for field testing technicians and lab testing technicians and the commentary provides information on certification that constitutes qualification. This provision is expected to vastly eliminate errors in specimen sampling and testing. Inaccurate test results have been extremely costly to the masonry industry, and more specifically, to the masonry contractor.

In the 2016 cycle, there was a concerted effort to simplify the Code and Specification as much as possible. For example, there were two sets of inspection tables, one in the Code and one in the Specification. The inspection tables in the Code were deleted with a simple reference to the Specification inspection tables. Another simplification was merging the three tables for levels of inspection into a single table. This makes quality assurance tables much easier to understand and apply. The 2022 Committee continues the effort to simplify and clarify their portion of the Code and Specification.

One of the charges for the 2022 Construction Requirements Subcommittee is to put text into tables as much as practical. An example of this would be to look at the existing provision for the initial mortar bed joint. The existing language is:


3.3 B Placing mortar and units

  1. Bed joints at foundations – In the starting course on foundations and other supporting member, construct bed joints so that bed joint thickness is at least ¼ in. (6.4 mm) and not more than:
  2. ¾ in. (19.1 mm) when masonry is ungrouted or partially grouted.
  3. 1 ¼ in. (31.8 mm) when the first course of masonry is solid grouted and supported by a concrete foundation.


This section may be revised to something like this:


3.3 B Placing mortar and units

  1. Bed joints at foundations – In the starting course on foundations and other supporting member, construct bed joints in accordance with the following:


First course condition Minimum, in. (mm) Maximum, in. (mm)
Ungrouted or partially grouted ¼ (6.4) ¾ (19.1)
Solidly grouted and supported by a concrete foundation ¼ (6.4) 1¼ (31.8)


The TMS 402/602 conducts business as an open process which means that anyone can participate. Participation ranges from active involvement within the committee to an outside individual making suggestions for changes to the Code or Specification.

Meetings of the TMS 402/602 committees are held twice a year and the venue moves throughout the country making physical attendance more convenient for those participating in the process. As stated earlier, the process is open which means that anyone interested is invited to participate. Rather than object to certain Code provisions which may not make sense, contractors are encouraged to participate in the process. The form of participation can range from attending meetings, or offering proposals to change the Code, either directly to the Subcommittee or through a Subcommittee member. To find out more about The Masonry Society and the TMS 402/602 Committee process, visit the TMS website (

Words and Photos: John Chrysler, PE, FTMS

About the Author: John Chrysler is the Executive Director of the Masonry Institute of America and has been a member of the masonry industry since 1968 as a contractor, licensed Civil Engineer and Certified Structural Masonry Inspector. He is a well-known author of numerous books and articles, including the popular “Reinforced Concrete Masonry Construction Inspector’s Handbook.” Chrysler serves on numerous committees and organizations, and is a past President of The Masonry Society. He also serves as current Chair of Committee TMS 402/602, which is responsible for the development and maintenance of provisions in TMS 402/602, Building Code Requirements and Specification for Masonry Structures that serves as the primary masonry reference for the International Building Code. He has served on the ICC/TMS Special Masonry Special Inspector’s Examination Committee since it began. You can be reach him at or 310-257-9000.