Could clearer communication have prevented a building collapse?
Many of you will be aware of the tragic collapse of the Champlain Towers South apartment building in Miami, Florida last month. An engineering report had flagged critical defects with the structure three years ago.
Many believe the collapse could have been prevented... so why didn't the engineering report spur the building management into action?
By Anthony*
I'm a structural engineering supervisor. Whilst when reading the Champlain Towers South report from 2018, I found myself reviewing it as if one of my engineers had written it.
The report would have never made it past my desk as it is. I wrote to my engineers after reading it, stressing the importance of a well written report. I am always on them to know their audience and avoid assuming that the reader knows the implications of technical subjects. I blame the way this report was written for the disaster as much as anything else.
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Team,
I’m sure everyone has seen the news about the catastrophic collapse of the Champlain Towers South building in Surfside, FL. The official death toll is now 11, but there are still over 150 people missing. I’m sure there will be sad news soon on what they find deeper in the rubble.
There has been a lot of discussion in the news about the 2018 engineering inspection of the building and what was found at that time:
<https://www.townofsurfsidefl.gov/docs/default-source/default-document-library/town-clerk-documents/champlain-towers-south-public-records/8777-collins-ave---structural-field-survey-report.pdf>
There were many instances of cracked and spalling concrete found, as well as severe problems with the pool deck and waterproofing. It was even noted that not repairing the pool deck and waterproofing would “…cause the extent of the concrete deterioration to expand exponentially.” Yet nothing was done with this information for over 2 years. There were no alarms going off, no talk about a potential building collapse, no emergency repairs.
Why weren’t people alarmed? I blame the report itself as a contributing factor in this massive loss of life. Note that I don’t technically fault the engineering that was performed. I am no building or concrete expert by any stretch of the imagination, but they seem to hit on the major problems identified above.
The problem is how the report is organized and how the critical information is presented, a disconnect between the engineers and the intended audience, and a failure to point out possible consequences and risk.
Organization and Presentation
Typically a report should have a summary of the report in the beginning where the reader is most focused. Per ANSI/NISO Z39.18-2005 “Scientific and Technical Reports – Preparation, Presentation, and Preservation” the body of the report should be in the order of:
Summary
Introduction
Methods, Assumptions, and Procedures, Results and Discussion
Conclusions
Recommendations
References
Instead, the Champlain Towers South report goes from introduction straight to discussion, organized by general topics lettered A thru K:
A. Flooding of individual units during hurricanes thru balcony sliding glass doors and windows.
B. Balcony tile preventing inspection of concrete slab and cracked tile.
C. Concrete spalling of concrete slab edges of balconies.
D. Balcony soffit deterioration and paint issues.
E. Deteriorated plywood at entrance soffits with possible mold underneath.
F. Water intrusion thru window frames and windows at the end of their service life.
G. Cracking of stucco façade.
H. Non-existence of window washing/suspension hooks.
I. Pressure washing the entire exterior and repaint.
J. Cracking and spalling of concrete columns, beams and walls in the parking garage and underside of concrete slabs.
K. Failure of previous garage concrete repairs.
Note the order in which these topics are presented. It starts with discussion about condo units flooding during a hurricane due to leaky windows and doors. This is an issue to any homeowner and something that should be fixed promptly to prevent damage to flooring, mold growth, etc, but there is certainly no immediate danger.
The report then progresses to discussing the balconies, and briefly touches on the impossibility of proper inspection due to installed tiles. Again, this all sounds rather mundane and cosmetic. Bad soffits are next with the possibility of mold, followed by more leaky windows, cracked stucco façade, hooks for window washers and then pressure washing & painting of the exterior. Hidden way at the bottom is a bit about cracking and spalling of structural concrete members at the base of the building in the garage and pool deck area. However, this is only said to require repair in a “timely fashion.”
Concealed and virtually unnoticeable under paragraph I is a brief discussion about waterproofing below the pool deck and entrance drive: “The failed waterproofing is causing major structural damage to the concrete structural slab below these areas. Failure to replace the waterproofing in the near future will cause the extent of the concrete deterioration to expand exponentially.” These are most likely the absolutely most critical two sentences in the entire report and they are hidden in a sub paragraph under pressure washing and painting the exterior.
There is no summary of findings. There is no listing of conclusions. There is no listing of recommendations. There were three separate paragraphs that were omitted from this report that would have allowed the critical findings to be highlighted and emphasized.
Additionally, the critical topics should have been presented at the beginning of the report to stress their importance and criticality. This report instead begins with a discussion on leaky windows which have zero overall impact on the structural integrity of the building.
Disconnect from Audience
I am often pointing out to my engineers the importance of writing to their audience. It does no good to write a formal technically complex instruction to a sheet metal mechanic explaining to them how to repair aircraft structure. They do not need to understand all of the theory behind the instructions and limitations (although some of this knowledge can certainly be helpful). However, mechanics certainly need to understand exactly how they should cut out damage, tool speed limits, minimum edge distances, allowable hole diameters etc.
Conversely, program managers do not need to know all of the specifics that a mechanic does, nor do they need to understand the technical details that are contained within an engineering analysis. They need to understand the scope of what must be done, the parts and tools required, the time and cost to complete the repair, etc to allow them to make program-level decisions. They also need to understand the likelihood of failure, and the consequences of failure.
We include an analysis of the likelihood and consequences of failure in almost every formal brief we produce. This allows program managers to quickly understand what must be done, how quickly it must be done, and exactly what will happen if nothing is done. We ensure that all briefs contain required information, include it in a concise and understandable manner, and accurately communicate the essence of a complicated and detailed engineering analysis without getting into the weeds.
In this instance, the target audience was the condominium association. In fact, the report is addressed to the treasurer of the association! It could reasonably be assumed that this association was not composed of a team of structural engineers or experts in the fields of reinforced concrete construction or repair. It could be assumed that the audience would not understand the definition or criticality of concrete spalling. They would also not understand the progression of minor damage to a critical level. What exactly is concrete spalling? How and why does it start? Is it poor construction or a natural condition as concrete structure ages? How does it progress and how fast does it degrade? What repairs can be done? How long do these repairs take, and what is the expected life of these repairs? Unless coincidentally possessed of specialized technical knowledge, the target reader is left with no real knowledge of the importance of what is being discussed.
The report does not explain at any point the cause, criticality, or progression of concrete spalling or other noted damage, and thus the audience is left not understanding many things that are immediately obvious to an expert in the field. This is a critical omission. Without the audience understanding exactly what the information in this report means to them at their level, and with the many of the findings described as almost simple cosmetic issues, the report can be easily dismissed as nothing more than a listing of issues that should be corrected, but not must be corrected.
Omission of Possible Consequences and Risk
The above noted issues with the report are serious, but they could have easily been overcome if only there was a concise and specific listing of the consequences of each of the listed issues, and the associated risk. This report lists the problems with the structures, but leaves it to the reader to understand the dangers and progression of each issue.
The report mentions water infiltration 4 separate times, but never covers the impact this intrusion or what would happen if allowed to continue.
The report cites the inability to completely inspect the balconies due to tile or other covering, but does not stress the importance of being able to completely inspect these structures. The report notes almost half of the balcony soffits showed evidence of deterioration under the painted finish, but fails to discuss the cause of this issue, other problems that this indicates, or the seriousness of this discrepancy.
Perhaps most importantly with the information coming out thru the media is the omission of the consequences of not correcting the waterproofing under the pool deck and entrance drive. There is no mention of the loading on this structure, no explanation of how the deterioration will actually “expand”, nothing on what is meant by “expand exponentially”, and nothing about the effect of the deterioration on the structural integrity of the building.
The report does not contain the words critical, risk, consequence, danger, threat, failure (except as used as failing to perform a duty or expected action), serious, or collapse. There is no obvious indication that there was anything found in the report that posed any threat beyond cosmetic matters or some water intrusion.
Bottom Line
When looking over mishap reports, the phrase “chain of events” is usually noted somewhere. In fact, for aircraft mishaps there is rarely a single incident that leads to the event, but rather a series of apparently unrelated, perhaps minor occurrences that finally result in the mishap. In hindsight, these events may appear obvious to everyone, but when they occurred they were missed. If any single one of these events was prevented, the mishap would have been avoided.
Usually these prevented events and avoided mishaps are unnoticed and disappear in day to day decision making. But when a catastrophe occurs, we are given the opportunity to look back and determine what went wrong, what was missed, and what could have been done differently to prevent it. In fact, almost all regulations and procedures have their roots in some horrible event – thus the saying that all regulations are written in blood.
In this instance of the Champlain Towers South collapse, I am sure there will be new regulations on building inspection intervals, allowable concrete damage, new building techniques and building codes. None of these apply to us in the aviation field, but by looking at all of the links in the chain, we can strive to prevent another mishap.
When writing any technical report, be sure to organize it thoughtfully and purposefully. Know your audience, understand their technical knowledge, and ensure you are communicating the necessary information to them. Be sure to clearly detail any risks and explicitly state what could happen if corrective action is not taken.
And if you ever see any situation that you are worried about, that you think could be one minor link in a potentially fatal chain of events, that you think could lead to failure, that you imagine could cause someone to lose their life, make damned sure that you communicate that clearly, loudly, and without any possibility of being misunderstood or ignored.
About the author
Anthony is a structural engineering supervisor from Jacksonville, Florida. For professional reasons, he has requested his last name be withheld.
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