3-Steps To Design Effective Joints

Picture1As a manufacturer of Expansion Joint Systems, we see a lot of mistakes on expansion joints that cause biding confusion and the inevitable change order. Some of the most common problems that are on construction documents include:

  • Wrong joint for the application location
  • Joint cannot be fire, sound or moisture rated
  • Wrong joint for the finish
  • No detailing or spec and details are different
  • No list of joints – just one model number for one of many joints
  • Manufacturer specified is out of business or does not make that joint

The image above illustrates a perfect example of a poorly designed restaurant. A bar-top counter was built directly on top of the expansion joint. Chances are the bar construction will not last long as there are limits as to what can be built over an expansion joint.

Here is a 3-step design process that will help reduce these costly errors:

  1. Plan out the joints early on in the design process. Early integration allows for adequate coordination and design decision making. Buildings with joints are large and require complex mechanical, electrical and plumbing systems which should be designed to avoid crossing an expansion joint.
  2. Develop the design and coordinate with engineers then schedule the joints, finishes and ratings. Things to consider include how to manage movement and building conditions, work with the structural engineer to determine a strategy, determine the width of the joint and locate the joints, how will aesthetics and performance be affected, thermal, water, sound and fire separations, floor traffic, loads and ADA access across joints.
  3. Schedule, show each detail and specify each type of joint.


Schedule Example:

Mark Location Substrate / Finish Type Detail
A First Floor Concrete/Carpet EM 1/A1.08
B Exterior Wall Masonry/Grey CP 3/A1.08
C Parking Deck Entry Concrete/SS CS 7/A1.08
D Parking Deck Floor Concrete/Grey CP 5/A1.08
E First Floor at Wall Concrete/Carpet CC 2/A1.08
F Roof See Roofing Details RR 11/A1.08

Nystrom understands the codes and complexities dealing with Expansion Joint Systems. To see how Nystrom can help on your next project, please visit www.Nystrom.com.