We recently hosted Sandra Lupien and Anthony Harvey on our Weekly Wednesday Free CEU webinar Series.

If you missed this session, want to rewatch it, or share it with a friend or colleague, you can now do so, as the recording is available below. In addition, they answered some of the remaining Q&A below, and your question may have additional follow-up below.  

The survey results reveal that attendees learned a great deal about the structural, environmental, and regulatory aspects of mass timber (MT) construction. Many were surprised to learn how tall MT buildings can be—some exceeding eight stories—and that there are already numerous MT projects across the U.S., including over 65 in Michigan. Participants gained new insights into mass timber’s fire resistance ratings (e.g., char calculations and ASTM standards), its favorable strength-to-weight ratio, and how it compares in durability and speed of construction to steel or concrete. A recurring theme was MT’s carbon-sequestering benefits and biophilic impacts on occupant mood, alongside cost-saving potential due to quicker assembly and pre-fabrication. Several responses highlighted unfamiliar MT types like dowel- and nail-laminated timber and clarified common misconceptions (e.g., heavy timber vs. engineered MT). Participants appreciated learning about 2021 IBC code updates, applications in multifamily/commercial settings, and the importance of early site planning and penetrations. Remaining questions or interests include exploring existing MT projects (especially regionally), understanding lifecycle comparisons with other materials, grant opportunities, and deeper dives into code compliance, cost estimating, and design integration for MEP systems and egress cores.

### Questions and Answers

1. **Question:** What kind of VOCs or off-gasses are produced and linger from CLT?  

   **Answer:** Reach out to Woodworks for assistance. The adhesives used are fossil-fuel-based polyurethanes, which cause some off-gassing, mainly in factories. In buildings, it’s minimal. There is ongoing research into bioadhesives that could enhance sustainability.

2. **Question:** Can dead wood from beetle kill or wildfires be used as mass timber?  

   **Answer:** Yes, sometimes. It depends on how long the wood has been dead or the extent of fire damage.

3. **Question:** How is Michigan building out its mass timber supply chain infrastructure?  

   **Answer:** Several entities are exploring expanding or starting operations for mass timber in Michigan. Commitments may emerge in the next 12-18 months.

4. **Question:** What are some of the largest barriers to the adoption of mass timber at scale?  

   **Answer:** The biggest barrier is that estimators often don’t know how to accurately estimate mass timber projects, leading to higher estimates than necessary.

5. **Question:** What is the cost difference between traditional mass timber framing vs engineered mass timber?  

   **Answer:** This is a complicated topic. There may be a cost premium for materials, but construction efficiencies can make mass timber cost-competitive. Estimators need to collaborate with suppliers for accurate costing.

6. **Question:** What is the rate of high fire resistance for mass timber?  

   **Answer:** Covered in 2nd hr. Reach out to Woodworks for assistance.

7. **Question:** How amenable are CLT floors to being modified for plumbing, HVAC, and electrical?  

   **Answer:** MEP considerations are a large topic. Reach out to Woodworks for assistance.

8. **Question:** Are the panels a tongue and groove connection to each other?  

   **Answer:** Only T&G decking. CLT has some side lap connection options.

9. **Question:** What about noise transmission?  

   **Answer:** Use built-up assembly to improve acoustics.

10. **Question:** How well do mass timber systems take to field modifications/renovations?  

    **Answer:** It would be handled just like any other structural system. Reach out to Woodworks for assistance.

11. **Question:** Do the panels need fire caulking between joints?  

    **Answer:** This depends. Reach out to Woodworks for assistance.

12. **Question:** What wall construction is typical exterior of the mass timber?  

    **Answer:** Exterior wall assemblies are very common, similar to steel and concrete projects with mass timber as the structural backup.

13. **Question:** Is there a way that radiant floor PEX can be integrated into mass timber floor?  

    **Answer:** Yes.