Mike Silvers, CPRC, Owner, Silvers Systems Inc. and FRSA Technical Director
During FRSA’s recent Board and Committee meetings in Melbourne, the Codes Committee made several recommendations for the Codes Subcommittee to consider as possible code modifications to be submitted during the 9th Edition (2026) Florida Building Code (FBC) triennial cycle. You may be thinking, “Didn’t we just adopt the 8th Edition (2023) FBC?” And you would be correct. It was adopted in December 2023. FRSA’s Codes Subcommittee will begin the first of many meetings in May, to start the arduous process of formulating the actual code modifications that we will eventually submit. I am sharing some of the subjects we will be discussing during this process to keep you aware of possible changes and to solicit any comments you may want to share about these reviews.
One issue the subcommittee will be discussing is the recovering versus replacement section of the code shown below and specifically, the section that addresses two applications of roof coverings. This section has been in the code for decades and has had several additions and changes over the years. The basic premise was not to overload the structure and to limit the stacking of too many roof systems, which among other problems, will make it very hard to track down the location of roof leaks in the upper roof as water must migrate between roof coverings and find a space to enter through the lower roof. Here is the current code:
2023 Florida Building Code, Existing Building, Eighth Edition
CHAPTER 7 – ALTERATIONS – LEVEL 1
SECTION 706 – EXISTING ROOFING
[BS] 706.3 Recovering versus replacement.
New roof coverings shall not be installed without first removing all existing layers of roof coverings down to the roof deck where any of the following conditions occur:
Exceptions:
These requirements are still very important; however, a lot has changed since these provisions were first introduced. The advent of a high R value above deck rigid insulations, single-ply roof coverings and the application of lightweight insulating concrete over existing roof coverings all create the need to review these sections. Items to consider that apply to this subject include the following items where two roof systems exist:
Another recommendation for the subcommittee to consider is the subject of possible changes to address the flashing, coping and terminations sections. The titles of these sections are shown below. These sections have also been amended multiple times and need to be reviewed for consistency and to possibly incorporate new materials and methods.
2023 Florida Building Code, Building, 8th Edition
CHAPTER 15 ROOF ASSEMBLIES AND
ROOFTOP STRUCTURES
SECTION 1503
WEATHER PROTECTION
1503.1 General.
1503.2 Flashing.
TABLE 1503.2 METAL FLASHING MATERIAL
1503.2.1 Locations.
1503.3 Coping.
2020 Florida Building Code, Residential, 8th Edition
CHAPTER 9 ROOF ASSEMBLIES
SECTION R903
WEATHER PROTECTION
R903.1 General
R903.2 Flashing
R903.2.1 Locations.
TABLE R903.2.1 METAL FLASHING MATERIAL
The committee also recommended that the subcommittee review and address the following FEMA Hurricane Ian MAT Report recommendations shown below:
Shingle hip and ridge failures have been on FRSA’s radar since Hurricane Irma, where it became clear that this was a widespread problem. Subsequent hurricanes have reinforced the validity of those concerns. We will try to get out in front of any changes with workable suggestions and to oppose changes that could be problematic. We have also observed failures of hip and ridge details used on metal roofs and will review that information. FEMA’s interest in underlayment lapping at hips and ridges will also be addressed.
We will consider a change to address the life safety issue of coated (obscured) skylights that match the metal panel profile on metal building type roofs (i.e. R panels). The intent will be to prevent unanticipated fall-throughs when transversing across the roof by clearly defining where skylights that have been obscured are located.
During the 8th Edition FBC (2023) code cycle, FRSA introduced several modifications to the underlayment requirements in the HVHZ portions of the code. These changes have, for the first time, allowed for the use of self-adhered underlayment applied direct to deck in the HVHZ. This offers an additional option that has been used throughout the rest of Florida for many years. We also made changes that would require that all tile underlayment's demonstrate the ability to resist wind uplift pressures based on ASCE 7-22 using either FM 4474 or UL 1897-12 vacuum chamber test. Unfortunately, the interpretation of these changes continues to allow prescriptive underlayment's that refer to generic material that vary wildly in performance to be used. The Miami-Dade Notice of Acceptance (NOAs) are being issued when a -45 uplift resistance threshold is demonstrated even though this is well below the typical design pressure required in ASCE 7 for structures in the HVHZ. We have been given direction to review the HVHZ portions of the code including the roof application standards (RAS) and testing application standards (TAS) to facilitate the goal that all tile underlayment meets ASCE 7 pressures using the FM and UL test methods previously approved by the Florida Building Commission. As we did when making the last changes, we will engage with Miami-Dade County to request their cooperation to address these critical changes. I hope that our efforts will be more successful than before and limit the acrimony before the Commission.
These are not the only modifications that we will be proposing and some of these may not make the final cut but, rest assured, we will work diligently to improve the resilience of roof systems installed in Florida through well-reasoned and thoroughly debated changes in the FBC.
Mike Silvers, CPRC, is owner of Silvers Systems Inc. and is consulting with FRSA as Director of Technical Services. Mike is an FRSA Past President, Life Member, and Campanella Award recipient and brings over 50 years of industry knowledge and experience to FRSA’s team.
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