Mike Silvers, CPRC, Owner of Silvers Systems Inc. and FRSA Technical Director
Nothing else has come close to having an impact on Florida’s Building Codes as hurricanes. Their regular occurrence and the threat that they create cannot be overlooked. Each major storm leaves in its wake not only damage and disruption but also renewed calls to strengthen the building codes. The length of time that it takes to implement these changes has varied. Some of the variation has had to do with timing changes in the early code adoption process and how it has evolved, but more recently it has more to do with when a major storm takes place during the three-year code cycle. If a storm hit last hurricane season (2021), then potential changes could have been proposed for the 2023 8th Edition of the Florida Building Code and been adopted only two years later. However, if we have a major storm this season, the changes could not be made until the 2026 9th Edition of the code is completed and implemented in December of 2026, over four years later. A few months can change the tale drastically on the time needed and available to implement changes. Let’s consider a few storms and the direct impact they have had on the code.
4 Recent Major Florida Hurricanes
Andrew – August 1992 Homestead (Southeast Florida)
Charley – August 2004 Cayo Costa (Southwest Florida)
Irma – September 2017 Cudjoe Key (Keys/Southwest Florida)
Michael – October 2018 Mexico Beach (Northwest Florida)
6 Lesser Florida Hurricanes
Opal – 1995
Frances – 2004
Ivan – 2004
Jeanne – 2004
Dennis – 2005
Wilma – 2005
As you can see, we’ve had 10 hurricanes that have had a significant impact on Florida in the 30 years since Hurricane Andrew. It doesn’t take a mathematician to see that we’ve averaged a significant storm every three years. So, it is obvious why there continues to be pressure to build more resilient structures and roof coverings.
On August 24, 1992, Hurricane Andrew hit South Florida with 165 mph winds. 26 lives were lost, over 250,000 people were displaced and $26 billion in damage was done.
There were serious concerns about the ability to maintain the property insurance market in the state (some things seem to never change). Florida’s citizens demanded that our buildings better withstand storms like Andrew. So, in 1996, Governor Lawton Chiles created the Governor’s Building Code Study Commission to evaluate Florida’s building code and to provide recommendations to reform and improve the building code system. Those recommendations included:
■ Adopting a single building code for use statewide, called the Florida Building Code.
■ Creating an independent Commission to update and maintain the code.
■ Creating of a product evaluation and approval system for many building materials.
In 1998, most of these recommendations became law and the Florida Building Commission and The Florida Building Code (FBC) were created. The adoption of these requirements and the creation of the FBC was a very complex and sometimes contentious process. One major issue for the roofing industry was attempting to adopt a truly statewide building code. South Florida interests were determined to maintain portions of the South Florida Building Code for Miami-Dade and Broward counties. This eventually led to inclusion of the High Velocity Hurricane Zone (HVHZ) portions of the code. The first Florida Building Code was created and included many stringent requirements based on lessons learned from Hurricane Andrew. It was implemented on March 1, 2002. It included the introduction of the High Velocity Hurricane Zone (Miami-Dade and Broward Counties) and a separate subcode contained the Roofing Application Standard (RAS) and Testing Application Standard (TAS). This 1st Edition of the of the FBC also made significant changes to the roofing sections of the previous Southern Building Code Congress International (SBCCI) or legacy
versions of the code.
After Hurricane Andrew and before the implementation of the FBC, FRSA and the roofing industry were already improving the resiliency of roof systems by promoting the use of better materials and improved application methods. The first FRSA-NTRMA (now TRI) tile installation manual is a good example. It was adopted as a Reference Standard in the 1999 Standard Building Code and later in the FBC.
In 2004, Florida experienced one of the most active hurricane seasons on record. Charley was the strongest of the storms that hit Florida that year, but all of these storms did a great deal of damage, and roof damage was no exception. Damage was widespread and across all roof types.
Among the roofing issues that were observed during the 2004 storms were failures of the hip and ridge components on otherwise well performing tile roofs. These were of particular interest to the FRSA-TRI Tile Committee, which added improved instructions for hip and ridge attachment to the manual in response to those observations.
Hurricane Dennis primarily affected the western portions of Florida’s panhandle but caused significant damage where it struck and, as usual, roof systems took the brunt of the storm. Hurricane Wilma was one of several recent storms that crossed the entire state. This time the hurricane made landfall in Southwest Florida near Cape Romano with 120 mph winds. This is a relatively lightly populated area so most of the damage to structures was done as Hurricane Wilma exited Florida on the East Coast.
Hurricane Katrina also occurred in 2005. Although it didn’t make landfall in Florida, the devastation it created had significant impacts on the International Building Code (IBC) and, through that code, the FBC as well.
The effects of the four storms in 2004 and Dennis and Wilma in 2005 affected not only the 2007 FBC but also the 2009 Supplements to the Code. These changes were the most significant for the roofing industry since the FBC’s inception. For the first time, the act of replacing a roof system required roofing contractors to address elements of the structure that were not part of the intended work. They included mandatory roof decking reattachment, secondary water barriers and potential evaluation and correction of the roof-to-wall connections as well as many additional requirements. Many of these requirements were placed in the Existing Building Code subcode that was newly adopted in 2004. The requirements for a roof diaphragm evaluation that was inserted at that time was amended to create a clearer trigger for the evaluation of “where a reroof permit is required.”
Between Hurricane Wilma in 2005 and Irma in 2017, Florida didn’t experience a single significant hurricane. Only the comparatively weaker Hermine and Matthew occurred in 2016. Even during this time with few hurricanes, changes to the FBC – many of which were based on observations of previous storms – continued to take place. Among those coming into the FBC via the IBC was the adoption of American Society of Civil Engineers (ASCE) document ASCE 7-10. The ASCE 7 reference standard is how we obtain the needed uplift resistance for roof systems as well as the loads on structures and their components. The result was one of the most dramatic increases in wind resistance that our industry experienced. Other changes were adopted that addressed better roof covering performance in high wind events.
The adoption of the 2014 5th Edition of the FBC included major changes to underlayment sections in the standard code areas (outside the HVHZ) of Florida including the elimination of ASTM D226 Type II (#15) and the introduction of self-adhering underlayment (SAU) including their application directly to the deck. Also in the 2017 6th Edition of the code, underlayment for most steep slope systems was consolidated into one section of the code. 2017 was also the first code cycle where the FBC was used as the base code. Previous versions of the code started with the IBC as the base code and required adding the previously made Florida-specific changes.
Hurricanes Irma and Michael
Hurricane Irma made landfall at Cudjoe Key on September 10, 2017 and caused major damage in the Keys and the Marco Island area of Southwest Florida. Again, roof damage was widespread, but it was obvious that both the frequency and the severity of the damage was much less than in previous storms of comparable intensity. The impact of the previous code changes were working, particularly when the latest codes had been applied.
One of the most unusual potential code restrictions we have seen was proposed in Monroe County (the Keys). It was intended to allow only metal roofs within its jurisdiction. Not only did it propose mandatory use of metal roof coverings for all new construction and reroofing regardless of slope, but it also was required for all repairs as well. FRSA and other roofing industry groups were successful in eventually defeating the ordinance.
Hurricane Michael was the strongest hurricane to make landfall in Florida since Hurricane Andrew. It hit the Florida Panhandle near Mexico Beach and Tyndall Air Force Base on October 10, 2018. The major destruction it caused was only somewhat limited by the comparatively light population for coastal Florida. This made it no less devastating for those affected. Hurricane Michael did, however, gives us a good opportunity to observe damage from a storm that was very close to design wind speeds. Much like Hurricane Irma, it was plain to see that newer structures as well as components and claddings were performing much better. This was particularly clear when it came to roof coverings. A noticeable improvement was the performance of SAU applied direct to deck as a secondary water barrier (SWB) compared to standard mechanically attached underlayment. The reduction in interior
damage on structures where a SAU was used was obvious and widespread.
The 2020 7th Edition of the FBC included changes that were suggested based partially on observations from these storms. They included the adoption of the so-called sealed deck underlayment requirements that attempted to enhance the performance of SWB. The roof deck attachment and roof-to-wall connection provisions were expanded to all applicable structures with wood decks. The trigger for the roof diaphragm evaluation was changed to deck replacement, not reroofing. The use of salvaged tile for repairs
was clarified. Also added were more stringent sheathing requirements for new residential construction. The new ASCE 7-16 Reference Standard with its additional roof zones and increased pressures was implemented as well. The adoption of this burdensome standard was strongly opposed and almost successfully eliminated from adoption due to testimony by FRSA and many
other roofing industry interests. In the end, we convinced a majority of the Roofing TAC and Commission members of our concerns, however we fell just short of the super-majority votes needed. Most contractors realize just how disrupting its adoption has been.
Looking Ahead
We are currently in the process of adopting the 2023 8th Edition of the FBC. Our proposed modifications have all been submitted. No additional new modifications can be proposed. The potential changes should not be too onerous depending on how successful we are in helping to shape their adoption. The likely adoption of ASCE 7-22 will return us to three roof zones again and will reduce some of the highest pressures. This will also require a review of the FRSA-TRI tile manual. One other major issue for FRSA is changes in underlayment sections of the HVHZ portion of the code. The goal is to bring the improved underlayment and secondary water barrier provisions up to the standards used in the rest of Florida. The roofing industry will be well served by consistent
requirements throughout Florida. The residents, insurers and insureds in all of Florida deserve the same level of protection and the
option of choosing the best secondary water barriers. When another major storm hits that area, the currently weaker requirements
in the HVHZ have the potential to affect all of Florida through property insurance rate increases, insurance availability and the need to bail out Citizen’s policies.
The renowned Colorado State University meteorologists predict 19 tropical cyclones this year with nine of them reaching hurricane strength. As this review of the previous hurricanes demonstrates, Florida continues to be in the crosshairs of these storms. They can and do strike all areas of the state. If we remain vigilant and continue to install more resilient roof systems, we can be a big part of lessening the economic impact and, more importantly, to help reduce the personal upheaval of being displaced from your home.
Mike Silvers, CPRC is owner of Silvers Systems Inc. and is consulting with FRSA as Technical Director. Mike is an FRSA Past President, Life Member and Campanella Award recipient and brings over 40 years of industry knowledge and experience to FRSA’s team.
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