Florida Building Code, Existing Building, Chapter 6, Section 611.1.1 says this:
“Not more than 25 percent of the total roof area or roof section of any existing building or structure shall be repaired, replaced, or recovered in any 12 month period unless the entire roofing system or roof section conforms to the requirements of this code.”
Read on its own, that is the sentence that used to force full replacements. Cross 25 percent, bring the whole roof to current code.
Then 2022 changed it
Senate Bill 4-D and its House companion HB 3D amended section 553.844 of the Florida Statutes to add an exception.
If the roofing system or roof section was built, repaired, or replaced in compliance with the 2007 Florida Building Code or any later edition, then only the repaired, replaced, or recovered portion has to meet the current code. The rest of the roof stays as it is.
So the question is what your roof already meets
The 2007 code is what introduced two requirements worth knowing about. A roof replacement had to include a secondary water barrier, and roof-decking attachments and fasteners had to be strengthened or corrected during reroofing.
That second one is exactly what a Hillsborough County Progress Check inspection looks at.
Worth being precise aboutSB 4-D did not delete the 25 percent rule. It added an exception. A roof that does not meet the 2007 code is still exposed to full replacement.
Source: Florida House of Representatives staff analysis of HB 3D (2022D), Roof Repair, Replacement, and Recovering Requirements. The current code is the 8th Edition (2023). The 9th Edition takes effect December 31, 2026.