The Stairbuilders and Manufacturers Association (SMA) continues to lead the industry with its collaborative research and testing efforts. With the receipt of a 2023 USDA Forest Products Services Laboratory Wood Innovations Grant, SMA members working collaboratively with Mississippi State University (MSU) and Simpson Gumpertz, & Heger (SGH) are well into the testing and modeling phase of the project.

Beginning in Fall 2023, the testing collaborative met both in-person and virtually to define parameters for test samples and testing methodologies that contribute to full-scale stair testing at the SGH laboratory later this year. To date, SMA members have contributed a substantial amount of time and materials in support of testing efforts and to meet SMA’s obligations for matching of grant funds.

Currently, the final three of eight sub-elements are being tested at the MSU Wood Science laboratory in Starkville, Mississippi. Data from the first sub-element tests has been shared with the SGH engineering and testing teams where the data is being input into a predictive modeling program. Full-scale stairway models are currently in development that include the sub-elements that have undgone testing in MSU’s laboratory as a part of this project as well as previous SMA/MSU joint testing efforts. The purpose of the full-scale testing is to validate the performance of stair joinery and fastening methods using standard hardwood components. Ultimately the goal of this project is to have a software tool that will be able to verify the structural performance of stair systems without undergoing a full engineering review.

Sub-elements undergoing testing for this round of development and grant funding include but aren’t limited to:

  • Top of Post Cap to Newel
  • Single Rise Gooseneck Fitting
  • Two Rise Gooseneck Fitting
  • Corner Mounted Starting Newel
  • Face Mounted Starting Newel
  • Intermediate Rake Newel
  • Opening Newel at Top of Flight
  • Intermediate Balcony Newel
  • Top Mount Newel (prior testing)

Currently the only species being tested is red oak. However, through prior SMA testing done in conjunction with MSU, structural values for appearance grade hardwoods have been verified and will be used in conjunction with the predictive modeling software to be able to give a wide range of options for design.

The current phase of the project which includes the full-scale testing at SGH’s laboratory is scheduled for completion mid-year 2025. SMA is currently in the process of applying for additional funding for the next phase of the project which will focus on further testing as well as the build-out of the software tool for use by engineers and stair manufacturers.

If you would like to be involved in this testing initiative or SMA’s ANSI Standards or Building Code Advocacy programs, please contact Ashley Goodin at ashley.goodin@stairways.org.