BY THE BOOK – JANUARY 2017
How familiar are you with the ANSI American National Standards Specifications for the Installation of Ceramic Tile? (ANSI stands for the American National Standards Institute.) If you aren’t, and you’re in the tile installation business, it’s time you pay attention. ANSI Standards are a tile installer’s best friend!
Why tile installers should study the TCNA Handbook and ANSI Specifications
For continued success, tile installers should study the TCNA Handbook for Ceramic, Glass and Stone Tile Installation and ANSI Specifications, retaining as much as possible, or at least knowing where to find the answers. These books can be your best friend as this article – based on a true story – explains.
Here’s how the story goes.
After successfully completing the Large Format Tile and Substrate Prep test – one of the ained in the Advanced Certifications for Tile Installers (ACT) program – an installer returned to work installing tile while also being the jobsite superintendent.
On this particular day, the superintendent was representing his company at a pre-job conference with the architect since the business owner was not available.
The architect reviewed the scope of the job involving the tile installation and said that the job included a 12” x 24” non-rectified porcelain tile which was specified to be installed in a running bond (brick pattern), at a fifty percent offset and a 1/32” grout joint.
When current ANSI Specifications call for a different application
The now ACT-certified installer politely informed the architect that the current ANSI Specification, A108.02 under section 4.3.8, calls for a much different application.
Here follow the criteria excerpted from ANSI A108.02 Section 4.3.8 regarding grout joint size, particularly in relation to the tile size, dimensional precision, and offset pattern:
4.3.8 Grout Joint Size:
To accommodate the range in facial dimensions of the tile supplied for a specific project, the actual grout joint size may, of necessity, vary from the grout joint size specified. The actual grout joint size shall be at least three times the actual variation of facial dimensions of the tile supplied. Example: for tile having a total variation of 1/16” in facial dimensions, a minimum of 3/16” grout joint shall be used. Nominal centerline of all joints shall be straight with due allowances for hand-molded or rustic tiles. In no circumstance shall the grout joint be less than 1/16”.
220.127.116.11 Running Bond/Brick Joint Patterns:
For running bond/brick joint patterns utilizing tiles (square or rectangular) with any side greater than 15”, the grout joint shall be, on average, a minimum of 1/8” wide for rectified tiles and, on average, a minimum of 3/16” wide for calibrated (non-rectified) tiles. The grout joint width shall be increased over the minimum requirement by the amount of edge warpage on the longest edge of the actual tiles being installed. For example, for a rectified tile exhibiting 1/32” edge warpage on the longest edge, the minimum grout joint for a running bond/brick joint pattern will be 1/8” + 1/32” or 5/32”, on average. Of necessity, in any installation, some grout joints will be less and some more than the average minimum dimension to accommodate the specific tiles being installed.
18.104.22.168 Running Bond/Brick Joint Offset:
For running bond/brick joint patterns utilizing tiles (square or rectangular) where the side being offset is greater than 18” (nominal dimension), the running bond offset will be a maximum of 33% unless otherwise specified by the tile manufacturer. If an offset greater than 33% is specified, specifier and owner must approve mock-up and lippage.
The ANSI Standard-based solution
The installer paraphrased the ANSI specification saying, “The tile is to be installed in a running bond offset at a maximum of 33% with a 3/16” grout joint.”
The architect asked the installer where he found this information and how he knew it so well. The installer showed the architect the portion of the ANSI book containing that standard, and told him that he became aware of this and many other aspects of the industry standards through his studies in preparation for the ACT certification tests. The architect reviewed the ANSI listing and agreed that the specifications would be modified to follow the standard that the installer had described. The tile was installed successfully and everyone involved was satisfied with the end result.
The owner of the tile company, who was absent through this process, is convinced that had they installed the tile as originally specified, the job would have been rejected due to edge lippage, requiring it to be removed and replaced.
Get to know the tile installer’s best friend!
The ANSI Standards-based knowledge saved this contractor a significant amount of time and potential expense. Using knowledge wisely can reap large benefits. Wouldn’t you agree?
Have you encountered tile installation situations where the ANSI Standards were truly your best friend? Please share your experiences with us at [email protected]
The Ceramic Tile Education Foundation (CTEF) is an educational institution that offers local, regional, and national training programs for consumers, installers, construction professionals, architects, designers, building inspectors and sales associates interested in the sale and installation of ceramic tile. Find out more at ceramictilefoundation.org.