2023 Florida Residential Code

Product Requirements

Products must be certified and labeled to show they conform to their established ASTM standard:

• R301.9 (R703.11.1 and R703.13.1) requires cladding and soffit to meet the wind loads in the code.
• R703.14.1.1.1, R703.11.1.4 and R703.14 Starter strip is required at the initial course of vinyl, insulated vinyl and polypropylene siding. See page 8 of Building Code Reference Guide for detail.
• R703.11.1.5 and R703.14.1.1.2 requires utility trim below windows and at the top of walls where the top of siding is trimmed. See page 8 of Building Code Reference Guide for detail.
• R704 prescribes requirements for soffit and fascia. R704.2.1, for vinyl and aluminum soffit, panels shall be installed with fasteners at both the wall and subfascia; if the soffit span is greater than 12", additional intermediate nailer strips shall be used. See drawing on page 8 of Building Code Reference Guide.
• R704.3 prescribes the installation method for aluminum fascia, depending on whether the design wind pressure is 30 psf, 30-60 psf, or greater than 60 psf. This section includes fastener placement and spacing requirements, as well as areas with greater than 60 psf, which require fascia to be wrapped around the corners of the soffit, depending on whether it is a gable or hip roof.
• R703.14 Requires polypropylene siding panels range in size and are unique. Manufacturer's instructions should be reviewed because, in many cases, fastener spacing may be less than 10" on center. It must be installed over some type of wood sheathing (nailable substrate) with a minimum thickness of 7/16".

Installation Requirements

The following are prescriptive and performance installation requirements for Florida:

• R703.11.1 In general, vinyl and insulated vinyl siding meet the wind loads in accordance with Table R301.2(2) and Table R301.2(3) when installed 16" on center using roofing nails, although variations are allowable, including other approved fasteners like staples and screws, when following manufacturer’s instructions. Prescriptive requirements for vinyl siding installation include that non-corrosive roofing nails that can penetrate the nailable substrate at least 1 1/4" must be spaced no more than 16" on center for horizontal siding and 12" on center for vertical siding and according to the manufactured installation instructions.
• R703.14.1 Polypropylene siding must be installed over wood sheathing. It cannot be installed over foam sheathing only. Non-corrosive roofing nails or other approved fasteners must penetrate the nailable substrate at least 1 1/4". Check manufacturer's instructions for proper spacing.

Considerations for High-density Settings

• R703.14.3 When installing polypropylene siding in high-density settings (less than 5' to property line), the product must have a certified ASTM E84 test report, based on the code requirement. Note: Does not apply to certain walls that are perpendicular to the fire serration distance measurement, like townhouse front and rear elevations.

2023 Florida Building Code

Chapter 14 provides general product and installation requirements for cladding

Product Requirements

Products must be certified and labeled to show they conform to their established ASTM standard:

• 1404.9 requires vinyl siding to be certified to ASTM D3679.
• 1404.12 requires polypropylene siding to be certified to ASTM D7254.
• Table 1405.3(3) counts vinyl siding and polypropylene siding as vented claddings and allows the elimination of vapor retarders because of their strong moisture management characteristics.
• Insulated vinyl siding and backed vinyl siding are not addressed in the Florida Building Code (FBC). Building officials may rely on code compliance reports for verification based on the established standards for the product categories, ASTM D7793 and D7445.