2024 Changes to the Florida Building Code
- Jeff Littleton
- Last Updated February 10, 2024
Table of Contents
2024 Changes to the Florida Building Code
December 31, 2023 saw the 8th edition of the Florida Building Code (FBC) come into effect with updates to the existing 7th (2020) edition guidelines. As a roofing tile distributor, All Points Tile and Slate recognizes the significance of staying informed about these changes for new buildings and roofing projects.
These updates reflect Florida’s commitment to enhancing safety, sustainability, and overall structural quality. The 8th Edition impacts various aspects of building design, construction, and roofing practices, making it must-know information for roofing professionals. In this article, we will cover the key modifications to the FBC specifically for roofs in 2024.
What is the most current edition of the Florida Building Code?
The latest edition of the Florida Building Code is the 8th Edition, effective December 31, 2023 for 2024. This edition is a result of the 7th Edition (2020) FBC and approved supplements, and will undergo a periodic update every three years (as specified in sections 553.73(3) and (7) of the Florida Statutes). Additional updates will be implemented throughout following 6 months (until June 31, 2024).
The updates to Florida’s Building Code introduce several changes for roofing, many of these correcting (and clarifying) spelling and grammatical issues. For example,
- references to Dade County have been updated to Miami-Dade,
- “selfadhering” is corrected to “self-adhering”
The 8th edition of the FBC addresses underlayments and nail penetration depth, steep slope underlayments, solar panels, and identifies what types of structures fall under FBC requirements. The update also clarifies common disagreements in the 25% Roof Replacement guidelines.
Underlayment and installation
Updates directly relating to underlayments (steep slope and asphalt) and installation can be found in 1518.2.1. For asphalt shingles, metal roof panels, mineral surfaced roll roofing, slate, and slate-type shingles, two layers of underlayment must be installed. We’ll go into more detail about
- Asphalt Underlayment
- Steep Slope Underlayment
- General Installation
- Installation of mechanically fastened roof tile systems
Asphalt Underlayment
The underlayment should be ASTM D226 Type II or ASTM D4869 Type III, Type IV, or ASTM D8257. The installation involves applying a strip of underlayment for the first course, which is half the width of a full sheet, starting at the eaves and sufficiently fastened. A full sheet of reinforced underlayment is used for the second course, starting at the eave. Subsequent courses should overlap half the width of a full sheet plus 2 inches, with all successive courses overlapping half the width of a full sheet plus 1 inch.
There are corrections for Section 1518.2.1, which involve changing the width dimension of the self-adhering polymer-modified bitumen membrane from 3-3/4 inches to 95 mm. This conversion was overlooked in previous sections but is now rectified in other areas of the Building and Residential codes areas.
Steep Slope Underlayment
The language from the 7th edition has been reworked to clarify the overlap for two-ply nailed underlayments. Previously, the descriptions resulted in inconsistencies in underlayment exposures that increased product waste and labor costs. For example, the first course required an additional inch of width for the strip, which made the remaining piece unusable.
In the new edition of the FBC, all types of (approved) underlayment materials are allowed – including any width sheet. High-Velocity Hurricane Zones (HVHZ) underlayment applications are similar. However, tin caps/tabs are still required.
Installation
The updated code introduces improvements in installing a two-layer underlayment system. This change addresses Item 3 in Section 1507.1.1.1 and is incorporated into FBC-Residential Section R905.1.1.1. The proposal now aims to establish consistent requirements for two-layer underlayment systems within and outside the HVHZ.
Table 1518.2.1 has two corrections. The first one addresses the correct standard, which should be ASTM D6757 instead of ASTM D675. The second correction involves changing the minimum nail penetration through sheathing or planks from 3/16 inches to 1/8 inches.
These changes aim to improve consistency and promote safer and more reliable roof installations across Florida.
Installation of mechanically fastened roof tile systems
The Florida Building Code has introduced additional underlayment modifications for installing mechanically fastened roof tile systems with direct deck and counter battens.
For roofs with a 4:12 or greater pitch, single-ply underlayments utilizing battens or direct deck are no longer referred to as “nail-on” underlayments, according to reference 3.01E.
The Roofing Application Standard (RAS) No. 120-20, addresses mortar and adhesive set tile application. The term “nail-on” has been removed for any reference to systems with mechanically fastened base sheets and cap sheets set hot, cold, or self-adhered.
By removing outdated and unnecessary references, FBC is focusing on uniformity and consistency for roofing professionals under RAS 130.
25% Roof Replacement Rule
The 25% Roofing Replacement Rule previously required roofs to be replaced if more than 25% of the roof surface was damaged. However, there have been updates to eliminate certain situations that took advantage of vague interpretations.
Now, you will only need to repair the damaged portion of the roof rather than replace the entire roof if only 25% of it is affected.
If your roof was constructed or replaced after March 1st, 2009, it will likely comply with the 2007 Florida Building Code. For homes built before March 1st, 2009, without a prior roof replacement, the previous 25% Rule still applies, necessitating a full roof replacement if more than 25% of it is damaged.
These updates aim to streamline the roofing repair and replacement process, providing property owners with more flexibility and cost-efficiency when addressing roof damage. By focusing on the affected portions rather than requiring full replacements, the code adjustment reflects a more practical and pragmatic approach to roof maintenance and construction.
Solar Energy Systems
With the growing desire for energy-efficient homes and businesses, the 8th edition FBC has made multiple updates to solar energy roofing systems. These changes are all about making sure that your rooftop solar setup is environmentally friendly, safe and reliable for years to come. These updates include:
Solar Equipment and Materials
When you’re setting up solar panels, they’ve got to meet UL 1703 standards to make sure they’re safe and perform well. If you’re connecting to the utility grid, your inverters need to follow UL 1741 standards. The mounting systems need to be listed under UL 2703 and installed exactly as the manufacturer tells you. These rules are all about making sure your rooftop solar setup is safe and reliable.
Building-Integrated Photovoltaic (BIPV) Roof Panels
BIPV roof panels serve as both your roof and solar generators. Section R905.17 states that when you use these panels, they must blend seamlessly with the rest of your roof. This way, you get efficient energy generation and a sturdy roof structure. The manufacturer’s instructions, including wind resistance(ASCE 7), fire classification (R902), installation, and the need for UL 1703 listings play a key role in these systems.
Underlayment and Material Standards
The code insists that underlayment should be installed according to Section R905.1.1, and any materials used must have UL 1703 listings.
Flashing
When using BIPV panels as your roof, special attention must be paid to the flashings that seal your roof. Wherever the solar system is interrupted or ends, flashing must be used to prevent moisture from entering the wall and roof through joints and intersections with parapet walls or other penetrations in the roof plane.
METAL FLASHING MATERIAL (Reference Table R903.2.1) | |||
Materials | Gage Minimum Thickness (inches) | Gage | Weight (lbf) |
Copper | 0.024 | X | 1 (16oz) |
Aluminum | 0.024 | X | X |
Stainless Steel | X | 28 | X |
Galvanized Steel | 0.0179 | 26 (zinc coated G90) | 26 (zinc coated G90) |
Aluminum-zinc coated steel | 0.0179 | 26 (AZ50 alum zinc) | 26 (AZ50 alum zinc) |
Zinc alloy | 0.027 | X | X |
Lead | X | 2.5 (40oz) | X |
Painted Terne | X | X | 1.25 (20oz.) |
Are mobile homes exempt from the FBC?
Yes and no. Mobile homes fall under multiple jurisdictions with varying codes and guidelines. When it comes to your roof, the data plate for your mobile home will show you what your roof load zone and wind zone (with maps) is designed for, under §3280.305(c).
Under Florida law, U.S. Department of Housing and Urban Development (HUD) is responsible for the manufacturing of mobile homes. However, because these homes are designed to travel, the Department of Motor Vehicles (DMV) has their own mobile home requirements.
When you’re setting up a mobile home at its site, it must be installed according to HUD standards and floodplain requirements of the FBC. If any repairs become necessary, it’s important to pay attention to restrictions governed by the Florida Administrative Code within the DMV.
Stay up-to-date with compliance
In light of the recent 2023 updates to the Florida Building Code, homeowners and contractors must stay informed about the changes and ensure their roofs remain compliant. With the discontinuation of the 25% Roof Replacement Rule in certain situations, it becomes even more essential to address roof damage promptly and follow the latest regulations.
At All Points Tile and Slate, we understand the importance of maintaining a durable and code-compliant roof. Our extensive inventory of replacement tiles caters to a wide range of roofing systems, ensuring you can find the perfect match to keep your roof up to code. Don’t compromise on quality or risk non-compliance.
Explore our inventory and safeguard your property with reliable and suitable roof tiles today. All Points Tile and Slate is a distributor you can trust for top-notch products that guarantee the protection and longevity of your roof.
The information on our blog is for educational purposes only and should not replace the advice of a professional roofer. For all roofing questions and needs, please contact our experts at 407-366-2521.