Florida
Do you need Class 4 shingles in Florida?
Hail is a risk anywhere strong thunderstorms form, but Florida's building code and wind mitigation rules are built around wind, not hail.
IBHS says hail can strike anywhere strong thunderstorms form. We did not find a source that ranks Florida's hail risk against other states, so we will not guess at it. What the code does say is clear: shingles must carry a wind test class that fits your zone. The shingle table in Section R905.2.6.1 of the 2023 Florida Building Code, Residential asks for a wind class, not an impact class.
That matters for what you pay for. A Class 4 shingle that is also Class F or Class H on wind meets the code. A Class 4 shingle with a weaker wind class would not meet it in a high-wind zone. Check both labels. Our guide to hail damage on Florida roofs covers what hail does to shingles here.
IBHS runs its own hail program, and it goes beyond pass or fail. Its lab fires hailstones made to match natural hail at roofing, records how the shingle breaks, and gives products a Performance Evaluation rating. Shingles rated Good or Excellent in the IBHS Hail Impact Ratings qualify for the FORTIFIED High Wind and Hail Supplement, a voluntary roof program. That is a different scale from UL 2218, so a Class 4 label and an IBHS rating are not the same thing.
Hurricanes are about wind and flying debris. The wind mitigation form's missile ratings are for windows, doors and skylights, not roof shingles. A Class 4 shingle is not a hurricane shingle.
The short version
Pick the shingle for wind first. If you also want a Class 4 hail rating, make sure the same product passed the wind classes your zone needs.
