Movement Joints

The issue of movement joints for various specific finish types is a matter of importance. This is the basis for this Technical Service Advisory.

1.      The over-arching principle that we should promote is the fact that Project Design Professionals are the responsible parties to design movement joints including frequency / composition / width / construct regardless of the finish type. We are not / should not be in the business of instructing design professionals on the design of movement joints.  Project design professionals have the responsibility to design movement joints within the appropriate finish type (and or within the underlying substrate type) in all types of projects.
With that said, if there are true dynamic expansion joints located in the substrate – they must be honored through the installation system regardless of the finish type. This is just well known basic construction industry-wide principle.

2.      Specific finish manufacturers also have a say in how their products are installed – they can also consult with specific project design professionals to provide their specific installation desires / criterion. A word of caution, we have to be careful not to fall back on what we have historically been comfortable with in recommending for this matter. For example, adhered concrete masonry veneer have very different movement joint requirements when compared to ceramic tile. Most stone veneer manufacturers require minimal movement joint accommodation in the finish layer (just honor movement joints in the underlying substrate).

3.      Lastly, specific industry guidelines for the specified finish type (i.e. ceramic tile follow Tile Council of North America’s expansion joint criterion – EJ171) can be referenced and used in absence of clear direction from Project Design Professionals. Just bear in mind that these are just guidelines and they will typically defer to Project Design Professionals.

For example:

-        For tile finishes – follow project design / instruction and appropriate industry info from the TCNA – EJ171 (see attached for more information)
-        For natural stone – follow project design / instruction and appropriate industry info from the TCNA and MIA – EJ171
-        For glass tile – follow project design / instruction and appropriate industry info from the TCNA – EJ171
-        For thin brick – follow project design / instruction and appropriate industry info from the BIA – Technical Bulletin 18A (see attached for more information)
-        For adhered concrete masonry veneer – follow project design / instruction and appropriate industry info from the MVMA for more information
-        For resilient flooring – follow project design / instruction and appropriate industry info from the resilient flooring industry (see the attached ASTM F710 Standard section 4.3.1 for more information)

Hope this information helps. Please let us know if you have any questions or concerns.

Regards, 
Arthur Mintie CSI, CDT | Technical Services Director