Tile roofs in Florida: what holds a tile down, adhesive foam or mechanical attachment

The attachment holds a tile roof down, not the tile. In Florida that attachment is sized roof by roof, and the numbers come from a manual and a product approval, not the code book.

The code points to a manual

Section R905.3 of the 2023 Florida Building Code, Residential, says clay and concrete tile "shall be in accordance with the manufacturer's installation instructions, or recommendations of FRSA/TRI Florida High Wind Concrete and Clay Roof Tile Installation Manual, Seventh Edition where the Vasd is determined in accordance with Section R301.2.1.3." Table R905.3.7, Clay and Concrete Tile Attachment, is marked "Reserved."

R905.3.2 sends minimum slope to the same manual, so the Florida code states no numeric minimum for tile. The 9th Edition (2026) Florida Building Code takes effect December 31, 2026.

Required moment against allowable moment

The manual says tile "shall be attached to resist the aerodynamic moment" from the building's design pressures, and to "secure tiles with nails, screws, foam/adhesive or mortar." Ultimate wind speed, exposure, roof slope, and mean roof height give the Required Uplift Moment from Table 2. The attachment comes from Table 3 or the foam adhesive manufacturer's published values, and its allowable moment must be equal to or greater than the required moment.

• Example from Table 2HB (hip roof, Exposure B, slope under 4.5:12, mean roof height 0 to 30 feet, 160 mph): 26.3 ft-lbf required in the low pressure zone, 27.9 ft-lbf in the high pressure zone.
• Example from Table 3 (low profile tile, 15/32 inch deck, direct deck): 39.1 ft-lbf for two ring-shank nails, 50.2 ft-lbf for two #8 screws.
• Fasteners go at least 1.5 inches from the head of the tile.
• Above a 60 foot mean roof height, engineering calculations must be submitted for permitting.

Those figures illustrate the method. The required moment for a given house is determined by site conditions and that house's design pressures.

Three methods, each with an approval

Eagle Roofing's Florida approval, FL7473-R11, says its tile "may be mechanically fastened, mortar-set or adhesive-set."

• Mechanical: nails or screws, rated in FRSA/TRI Table 3.
• Foam adhesive: per the manual, "Foam applied systems require FBC Product Approval." FL7473-R11 says attachment follows the adhesive manufacturer's Florida Product Approval and lists DAP Storm Bond FL14506, DuPont TILE BOND FL22525, APOC POLYSET AH-160 FL6332, and APOC POLYSET RTA-1 FL6276.
• Mortar: field tile mortar "shall be factory premixed and bagged," and wind resistance comes from the mortar manufacturer's FBC Product Approval.

Foam is sized by the paddy

Each adhesive approval sets paddy size and placement. The values below are allowable overturning moments, with margins of safety already applied, from the current revision of each approval as listed on floridabuilding.org on October 29, 2026: FL22525-R7 (non-HVHZ table) and FL6332-R13.

• DuPont TILE BOND, FL22525-R7, concrete flat or low profile, interdependent: two paddies 1 inch in diameter by 8 inches long, one to the underlayment and one at the headlap, minimum 16 square inches per paddy, 63 ft-lbf.
• TILE BOND, concrete flat or low profile, independent: two 2 x 2 x 4 inch pads, 65 ft-lbf. Concrete high profile, interdependent: 19 ft-lbf.
• APOC POLYSET AH-160 (HFO), FL6332-R13, clay or concrete flat or low profile: single medium paddy (2 x 7 inch, about 30 grams), 60 ft-lbf; single large paddy (2 x 10 inch, about 45 grams), 112 ft-lbf; two paddies (4 x 4 inch on the underlayment, 2 x 4 inch at the tile overlap), 55 ft-lbf.

Both tables assume a two-ply, hot-asphalt-applied "30/90 system" underlayment. Other underlayments must be listed specifically for use with that adhesive. AH-160 paddy gram weights vary by tile profile.

Both approvals limit who applies the foam. TILE BOND requires a factory trained "Qualified Applicator" approved by DuPont. AH-160 requires a valid Qualified Applicator Card from ICP and named dispensing equipment only.

Slope adds fasteners to foam

• From 2:12 up to and including 6:12: no fasteners required in addition to the adhesive.
• Over 6:12 up to and including 7:12: fasten every tile in the first course and every third tile every fifth course.
• Over 7:12: fasten every tile in addition to the adhesive.
• Exception: when battens and tiles with protruding anchor lugs are used, fastening is not required in addition to the adhesive.
• Staples cannot be used with adhesive set systems.

Edges, corners, hips, and ridges

Zone 3 is the high pressure zone; Zones 1 and 2 are low pressure. The manual sets zone width as "a = 10% of the width or 40% of the height, whichever is smaller, but not less than 3 ft." The Florida Building Code, Building volume, in 1507.3.6, sets perimeter fastening areas at three tile courses, but not less than 36 inches, from hips, ridges, eaves, and gable rakes.

On hips and ridges, the manual allows mechanical, adhesive-set, or mortar-set attachment with a minimum 2 inch headlap unless restricted by product design. Structural mortar there needs an FBC Product Approval and testing to ICC-SSTD 11-99. Job site mortar mixes may be used for cosmetic purposes and weather block only.

IBHS found that two decades of improvements in tile fastening were effective at decreasing damage severity in Ian.

Southwest Florida is not HVHZ

The Florida code defines the High-Velocity Hurricane Zone as Broward and Miami-Dade counties. Southwest Florida is outside it, though FEMA notes most of the area where Ian made landfall has been in the Wind-Borne Debris Region since the 2001 code.

Under s. 553.842(4), F.S., a statewide approval keeps local jurisdictions from "requiring further testing, evaluation, or submission of other evidence" when the product is used within its conditions, so a tile or adhesive with a current statewide approval does not need a Miami-Dade NOA in Lee or Collier. Under s. 553.842(9), F.S., a building official can still deny a specific application through a signed written report finding it inconsistent with the statewide approval. An approval's limits of use say whether it covers the HVHZ: Eagle's FL7473-R11 tile report is "not for use in FBC High Velocity Hurricane Zone jurisdictions," while FL6332-R13 for AH-160 lists both non-HVHZ and HVHZ.

The TAS 106 field verification and static uplift test for adhesive- and mortar-set tile is in FBC-B 1512.4.2.4, one of the HVHZ sections, and under 1512.2 applies in the HVHZ or where the jurisdiction has adopted those provisions. FEMA Recovery Advisory No. 3 (November 2004), voluntary guidance, recommends pulling at least one tile per square (100 square feet) to confirm foam contact area and location.

Weight on a shingle conversion

Eagle's 2026 specs list approximate installed weights of 970 pounds per square for Bel Air and Sequoia, 880 for Capistrano Florida, and 770 for Malibu Florida. FBC-R R908.2 requires the structural roof components to be "capable of supporting the roof covering system and the material and equipment loads that will be encountered during installation of the roof covering system." On a shingle-to-tile switch, that is confirmed per engineering.

What to ask on a tile quote

1. The tile's FL Product Approval number, revision included.
2. The adhesive or fastener approval number.
3. Which table or paddy pattern is used for the field, perimeter, and corner zones.
4. The hip and ridge method, and the mortar or adhesive approval behind it.
5. For foam, the installer's Qualified Applicator card.
6. Whether the underlayment is listed for use with that adhesive.
7. Whether a pull check will be done, and how many tiles.

PrimeBid Energy LLC is a Florida Certified Roofing Contractor working across Florida. A tile quote that names the approval numbers and the attachment for every zone is a roof you can check before it goes up.