Live Webinar: Understanding & Designing for Moisture Movement

Update: Watch the webinar on-demand here.


Join CopelandBEC’s Matt Copeland and GAF’s Jennifer Keegan in this live webinar today, September 24, 2025.

Learning Objectives

  1. Differentiate between how moisture moves through airflow and how it moves by way of diffusion through materials and assemblies. 
  2. Explain the code-mandated responsibilities regarding building envelope details.
  3. Develop strategies for meeting standard of care obligations related to including details in your design documents.
  4. Cover the new whole building airtightness testing requirements and how to be prepared for them on your next project.

A quick intro video is below and you can register here.

#16: Joe Lstiburekโ€”50 Years of Better Buildings

Joseph Lstiburek, B.A.Sc., M.Eng., Ph.D., P.Eng., is a principal of Building Science Corporation and an ASHRAE Fellow. Dr. Lstiburek received an undergraduate degree in Mechanical Engineering from the University of Toronto, a masters degree in Civil Engineering from the University of Toronto and a doctorate in Building Science Engineering from the University of Toronto. The Wall Street Journal refers to him as โ€œthe dean of North American building scienceโ€. When he is not in buildings he drinks red French wine and drives fast German sports cars โ€“ but never at the same time.


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Reports and repair designs, and when you need each one

In our line of work two of the most common deliverables are reports and repair designs. These documents are related, but distinct. They serve different purposes and are for different audiences. In this post we want to clear up some common misconceptions and explain when you need each one.

What are reports?

We use reports to communicate the results of our work.

Often this means presenting the findings of a failure investigation or condition assessment, and explaining what they mean. We might also use a report to document what we saw during a construction phase site visit, or our opinions regarding a construction dispute.

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Twenty five things Iโ€™ve learned in twenty five years

Here are some things I know about buildings, architecture, engineering, and construction after about a quarter century in the field.

  1. There is an enormous gulf between design and construction; we speak different languages and work from vastly different baseline assumptions.
  2. Most buildings have lots of things โ€œwrongโ€ with them; most of these defects donโ€™t actually cause problems.
  3. As an industry we produce approximately a hundred times as much documentation as we read.
  4. The โ€œright wayโ€ to do most things is knownโ€”weโ€™re not developing new physics hereโ€”but few people take the time to do it โ€œrightโ€.
  5. For better or worse, people in AEC learn on the job; college and โ€œbook learningโ€ are most helpful as a filter to identify raw talent, intelligence, and grit.
  6. Building envelope fundamentals are easy to understand and extraordinarily difficult to consistently execute.
  7. People will readily grasp onto the irrational (but convenient) hope that something will work this time, despite irrefutable evidence that the same thing has failed multiple times before.
  8. Confidence is convincing, even when unwarranted, and a lot of people are very confident in their ill-founded opinions.
  9. Certainty and construction donโ€™t go together; everything is best discussed in terms of risk and probability.
  10. We mostly learn from painful failures, and even then we learn very slowly.
  11. Imagination and emotion are a lot more powerful than track record.
  12. Building inspectors have way too much on their plates; most people think inspectors are responsible for checking far more than they actually have time, resources, or knowledge to inspect.
  13. Weโ€™re pretty good at building structures that donโ€™t fall down, but beyond that weโ€™re shockingly bad at consistently nailing basics like making buildings warm, dry, comfortable, and durable.
  14. The tools donโ€™t really matter. Many of the most impressive structures in human history were built (and have survived) without electricity, never mind AutoCAD, Revit, AI, AR/VR, drones, smartphones, tablet computers, ubiquitous internet, or digital photography.
  15. Architecture in 2025 is much more about โ€œdesignโ€ as an art form than it is about creating a functional โ€œmachine for livingโ€. This is neither good nor bad, but itโ€™s important to be aware of.
  16. Construction in 2025 is as reliant as ever on the knowledge, skill, dedication, mindset, and mood of the individual humans showing up on the job site each day.
  17. Itโ€™s easier to get good results by doing simple at 9 out of 10, rather than aiming for complex and sophisticated but only executing at 5 out of 10.
  18. Did I mention that no one reads anything?
  19. โ€œThis is better but it costs moreโ€ loses every timeโ€”your audience hears โ€œthis is better but itโ€™s also worseโ€… it doesnโ€™t make sense. If what you mean is โ€œthis is better because it will cost less in the long runโ€ then say that, and define โ€œlong runโ€ so people can make informed decisions.
  20. Nobody cares about the backstory; get to the punchline.
  21. Weโ€™ve apparently perfected construction drawings; they havenโ€™t changed in 25 years (or really ever).
  22. Contracts are of questionable utility; when things go sideways everyone gets pulled in and people claim whatever they want to claim, regardless of what the contract says.
  23. There are very few people on the planet who understand the difference between water vapor transport by airflow vs. by diffusion and how these relate to condensation risk. I like to think Iโ€™m one of them and I wrote a post about it to help spread the word (see also: #3 and #18).
  24. Roofing is like tires: unglamorous, essential, and needs regular inspection and periodic replacement to avoid dangerous failures. Yet people often ignore both their tires and their roofs.
  25. It is impossible to compare design and construction service proposals โ€œapples to applesโ€. Procuring these services through a low bid process is a waste of time for all parties involved.

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#13: John Straubeโ€”Educating Our Way to Better Buildings

John Straube, Ph.D., P.Eng., is an Associate Professor in the Faculty of Engineering at the University of Waterloo, where he is cross-appointed between the School of Architecture and the Department of Civil and Environmental Engineering. He is the author or co-author of over 100 published technical papers, author of the book High Performance Enclosures and co-author, with Eric Burnett, of Building Science for Building Enclosures.

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