Liability in construction doesn’t always stem from workmanship; it often stems from what wasn’t well documented, coordinated or clarified. By understanding these areas of risk and implementing best practices proactively, you can protect your project, team and reputation.
Danish philosopher Søren Kierkegaard once wrote, “Life can only be understood backward, but it must be lived forwards.” That sentiment resonates deeply in the construction industry. All too often, we don’t fully grasp what went wrong on a project until we’re looking in the rearview mirror. Fortunately, every mistake, whether ours or someone else’s—offers an opportunity to learn and improve.
In this article, I’ll share key lessons learned from real-world construction defect cases—errors that could have been avoided and proactive steps that could have reduced liability. The goal? To help you stay ahead of risk before it turns into a costly claim.
Picture This Scenario
Imagine you’re in the middle of a construction defects lawsuit. You’ve just finished a meeting with your attorney, and their first question is: “Do you have documentation showing you did everything right?”
That’s the moment when records, specifications, and proper communication become your best defense.
As you read on, consider what measures you can put in place now to avoid being in that position later. We’ll explore three areas that are currently creating significant challenges in the industry: (1) sound wall deficiencies, (2) water infiltration in exterior stucco walls (3) and third-party firestop inspections.
1) Sound Wall Deficiencies
Code Requirements and Testing Standards
The International Building Code (IBC) addresses sound isolation under Section 1207, which applies to common interior walls, partitions, and floor/ceiling assemblies separating dwelling units or separating dwellings from public or service areas.
The IBC mandates a minimum Sound Transmission Class (STC) rating of 50 in laboratory tests (or 45 STC if field tested) per ASTM E90. In practice, field-tested ratings are often interpreted as Apparent Sound Transmission Class (ASTC), based on ASTM E336.
How Long Are Third-Party Sound Tests Valid?
According to the ICC Guideline for Acoustics (2010), third-party sound test reports ideally should not be used if they are more than 20 years old. Yet, it’s common to see reports that are 30 to 40 years old still in circulation. Materials such as gypsum board composition or steel stud gauge may have changed over the years, potentially affecting the STC performance.
If you’re relying on third-party sound tests, treat them as you would a fire-rated wall assembly: verify that your field-built wall matches the tested assembly if it doesn’t, raise it up with the design team immediately.
What Influences STC Performance?
The entire wall assembly determines STC—not just a single product. Several factors play a role:
- Drywall type, thickness, and weight
- Stud gauge and spacing
- Type and placement of insulation
- Perimeter seal
- Use of decoupling methods such as double-wall construction, resilient channels, sound isolation clips, or foam isolators
Engineering Considerations
As structural engineers know, achieving sound performance must not come at the expense of structural integrity. It’s a delicate balance—one that requires thoughtful design. Wall assemblies must be framed to meet structural load requirements and deflection requirements while also considering flexibility, which plays a significant role in acoustic performance.
Here’s how to introduce flexibility into wall assemblies without sacrificing structural integrity:
- Use permanently flexible joint materials at perimeter joints, such as preformed sound-stop devices. These products offer two to three times more dynamic movement than traditional acoustic sealants and are resistant to shrinking, hardening, or cracking over time. For fire-rated walls, firestop device options are available that provide the same flexibility and durability while also meeting fire-rating requirements (see Figures 2 and 3).
- Decouple wall assemblies using resilient channels, sound-isolation clips, or foam isolators between studs (see Figure 4).
- Incorporate drywall control joints to reduce the risk of cracking and preserve flexibility (see Figure 5).
Another effective strategy is altering mass between wall sides. Using sound-dampening drywall, for instance, can improve STC by 5 to 8 points.
Other methods include:
- Using abuse-resistant board on one side and Type X on the other (+2 to 4 STC points).
- Unbalanced walls: double-layer drywall on one side versus a single layer on the other will not change the fire rating but it will improve the STC rating.
Fire Rating vs. Sound Rating
Question: If a wall is both fire-rated and sound-rated, which requirement takes precedence?
Answer: Technically, life safety always takes priority. However, from a building performance and occupant satisfaction standpoint, sound performance is critical to everyday quality of life. From a liability perspective, both must be treated as top priorities, especially when construction defects are involved.
Q: What is the difference between fire-tested and sound-tested walls?
A: The key difference is movement.
Building joints within fire-rated walls are typically tested for dynamic movement at the head of wall assemblies, as required by UL 2079. This means the head of the wall joint is cycled 500 times, opened to the max width of the joint assembly, and then fire tested. In contrast, sound-rated walls, tested under ASTM E90, are not subjected to movement testing.
But does this mean sound-rated walls don’t experience movement? Not at all. Sound-rated walls move just as much as fire-rated walls in the real world. The structural engineer determines the allowable dynamic movement and applies to all walls within a structure, regardless of their rating. The distinction is that sound-rated assemblies have no formal cycling movement requirement as part of their testing standard.
Bridging the gap between sound tests and real-world construction:
Complicating matters further, most third-party sound tests are conducted using 25-gauge steel studs spaced 24 inches on center—a configuration designed to maximize STC ratings in a controlled testing environment.
However, high-rise residential construction cannot rely solely on 25-gauge studs spaced at 24 inches. In practice, framed openings such as doors and windows typically require 20-gauge studs for adequate structural performance.
Additionally, head-of-wall top tracks in fire-rated wall assemblies are commonly constructed with a minimum of 20-gauge steel. Anywhere structural support is needed—for cabinet backing, handrails, televisions, or similar loads—wall assemblies must be upgraded to 20-gauge studs and often adjusted from 24 inches on center to 16 inches on center spacing.
These changes can significantly impact the acoustic performance initially anticipated by the original third-party test. That’s why it’s critical to evaluate the actual wall assembly conditions and not rely solely on idealized test reports.
Mock-Up Testing: A Practical Alternative
One effective alternative to field testing is mock-up testing, which allows project teams to assess real-world performance under actual construction conditions. A representative dwelling unit or suite is constructed using project labor, materials, and typical installation methods. This hands-on approach helps confirm whether the intended wall assembly meets required acoustic performance levels in practice—not just in theory.
If the mock-up performs well, it provides confidence that the assembly can be used consistently across the project. If results are marginal, the mock-up can help identify necessary adjustments in either installation techniques or design specifications before full-scale construction begins (see Figure 6).
2) Overcomplicating Stucco
I’m an adamant supporter of stucco for its many exterior cladding benefits. However, in my opinion, stucco has become unnecessarily complex. Unlike EIFS, which benefits from single-source manufacturing and unified installation details, stucco is far from standardized. It involves various manufacturers supplying everything from stucco accessories and plaster base (lath) to flashing, drainage mats, and water-resistive barriers. On top of that, regional differences in construction practices, climate variations, and conflicting opinions among code officials and building envelope consultants only add to the confusion.
Keep It Simple
Back in 2004, I took the stand as an expert witness in a trial. I was representing the contractor I worked for, who was being sued over water infiltration through the stucco cladding we installed a year earlier. The plaintiff’s attorney was calm and friendly at first—he could tell I was nervous. He started with a few simple questions to put me at ease… then went in for the punch.
Water infiltration occurred at the recessed windowsill, something that had been well documented. The attorney asked why the casing bead at the sill didn’t divert the water from getting inside. I answered confidently, “Because it’s not a flashing.” He followed up immediately: “Oh, so the casing bead let the water in?” See Figure 7.
Ouch. I had walked right into it—and he wasn’t wrong. That moment stuck with me. It made me realize that every stucco accessory should also act as flashing. It’s really that simple.
I’ve always believed that if you want something to work consistently, especially on a large scale, you must keep it simple—so everyone can understand it. As I mentioned earlier, EIFS benefits from single-source manufacturing and standardized installation guidelines. That keeps things straightforward.
The same principle applies to fire-rated assemblies. Take UL Design U465, for example. It includes metal studs, gypsum boards, insulation, and sound clip manufacturers. But it also provides clear instructions on how to build the wall, space the studs, and fasten the gypsum board. Again, clear direction keeps it simple.
Unfortunately, stucco doesn’t come with standardized details—but fortunately, I believe it can still be simplified.
Let’s go back to that courtroom moment and the lawyer’s question: “Why didn’t the casing bead prevent water from entering the building?”
It was a fair question—and one rooted in code. He was referring to IBC Section 1404.4, which states that flashing must be installed in exterior wall assemblies to prevent water intrusion and to direct water to the exterior. Flashing is required at all critical points—openings, penetrations, material transitions, and the base of walls—and it must be installed in a way that ensures water stays out of the wall system.
If we’re serious about keeping stucco simple, we need to think smarter about how components work together. One practical solution is to design stucco accessories that also function as flashing—dual-purpose components. This approach eliminates the layering and buildup caused by separate pieces and reduces the chances of flashing being skipped altogether (see Figure 8).
When you combine flashing with stucco accessories, you’re embedding water management directly into the cladding system. These accessories are essential to the stucco process, so they never get overlooked—unlike standalone flashing, which is often handled by another trade and can be forgotten. Integrating the two ensures proper installation and better performance, without added complexity (see Figure 9).
3) Third-Party Firestop Inspections
I still remember exactly where I was when I first heard that the International Building Code (IBC) had been revised to mandate third-party firestop inspections in certain buildings. The news hit hard—not because the change lacked merit, but because I immediately understood the impact it would have on installers. Having come from a background in construction defect investigations, where I regularly conducted third-party inspections on exterior sealant joints, I knew all too well the level of scrutiny that firestop sealants were about to face.
Inspectors already face a demanding job, but the challenge is amplified when dealing with multi-step firestop systems—especially when those systems are only visible to the inspector after completion. Without having seen the earlier phases of installation, how can an inspector be certain each step was performed correctly? (See Figure 10.)
That all changed with the adoption of the 2012 International Building Code (IBC), Section 1705.16, which introduced a significant shift in oversight. This provision mandates special inspections for fire-resistant penetrations and joints in specific building types—namely, high-rise structures and those classified under Risk Category III or IV. As a result, inspectors are now required to evaluate every component and connection with a far greater level of detail, ensuring comprehensive compliance across all firestopping and joint systems.
Examples of Risk Category III
Buildings and other structures represent a substantial hazard to human life in the event of failure, including but not limited to the following:
- Public assembly buildings with greater than 300 occupants
- Schools with greater than 250 occupants
- Colleges/universities with greater than 500 occupants
- Group I-2 occupancies with 50 or more
- Group I-3 occupancies
- Occupancies greater than 5,000
- Power plants, water treatment facilities
Examples of Risk Category IV
Buildings and other structures designated as essential facilities, including but not limited to the following:
- I-2 hospitals
- Fire or police stations
- Emergency shelters
- Emergency backup facilities
- Air traffic control towers
- Buildings having national defense functions
The IBC also specifies that special inspections must be conducted in accordance with standards such as ASTM E2174 (Visual Inspections) for penetration firestop systems and ASTM E2393 (Destructive Testing) for fire-resistant joint systems (see Figure 11).
Who Enforces This Code Requirements?
To limit your liability, you should familiarize yourself with what to expect from third-party firestop inspections.
When it comes to special inspections for firestopping, there’s no one-size-fits-all approach. Your local authority having jurisdiction (AHJ) ultimately determines the specific requirements, and there are a few key things to keep in mind:
- No guarantees—enforcement and expectations can vary.
- Standards may differ even within the same jurisdiction.
- Inspector qualifications (both company and individual) can vary by region.
- Inspection processes and the amount of oversight may differ project to project.
- Any project—not just high-rise or Risk Category III/IV—can be required to have a firestop special inspection; the building code provides only the minimum baseline.
Always check your firestopping specifications, especially Section 07840, to confirm what’s required.
One thing is certain: code changes consistently drive innovation—and firestopping is no exception. Most firestop installations take place in the upper third of the wall, above ceiling height, where the bulk of mechanical, electrical, and plumbing systems are also located. These crowded conditions make both installation and inspection particularly challenging. The growing demand for data center construction adds another layer of complexity, as these projects often require firestop systems that can accommodate high levels of dynamic movement.
To reduce liability and avoid costly mistakes once construction is underway, it’s critical to determine the anticipated movement requirements early in the design phase. Relying on the lowest-cost firestop solution and hoping it will suffice can result in far greater expenses down the line. If the expected movement exceeds ½ inch, traditional full-depth fire sealants may not be sufficient. In such cases, consider the growing range of preformed firestop devices, many of which are rated to handle up to 2 inches of total movement.
Manufacturers have responded to these evolving demands with innovative preformed firestop device solutions. These devices are installed fully cured, offer movement capabilities up to 4 inches, and can often be installed directly to the framing—well before mechanical, electrical, or plumbing systems are in place. This approach not only improves coordination but also reduces the likelihood of installation errors, helping contractors limit risk and improve project outcomes.
As codes evolve and construction complexity increases, the firestop industry continues to adapt through smarter products and proactive solutions. Understanding the movement requirements of your project—and planning accordingly—can make all the difference in delivering a code-compliant, high-performance building (see Figures 12 and 13).
Final Thoughts
Liability in construction doesn’t always stem from workmanship; it often stems from what wasn’t well documented, coordinated or clarified. By understanding these areas of risk and implementing best practices proactively, you can protect your project, team and reputation.
After all, we can’t always predict the future—but we can learn from the past. CD
Don Pilz is the director of technical services for the Association of the Wall and Ceiling Industry.
Photo Credits:
Figure 2. Provided by CEMCO, Smoke and Sound Stop Installation
Figure 3. Provided by Hilti, Bottom Track Seal
Figure 4. Provided by ClarkDietrich, RC Deluxe
Figure 5. Provided by Trim-Tex, 093X-V Fire Rated Control Joint
Figure 6. Field Sound Testing
Figure 7. Water Enters Though Perforated Casing Bead
Figure 8. Provided by CEMCO
Figure 9. Provided by Stockton Products
Figure 10. Provided by FireWise Consultants
Figure 11. Provided by FireWise Consultants
Figure 12. Provided by CEMCO, Fire Gasket Installation
Figure 13. Provided by Hilti, TTS Preformed Firestop Installation
