An existing building or portion thereof shall not be altered such that the building becomes less safe or energy efficient than its existing condition.
Exception: Where the current level of safety or sanitation is proposed to be reduced, the portion altered shall conform to the requirements of the Florida Building Code, Building.
In Group R-2 or R-3 buildings containing dwelling units and one- and two-family dwellings and townhouses regulated by the Florida Building Code, Residential, window opening control devices complying with ASTM F2090 shall be installed where an existing window is replaced and where all of the following apply to the replacement window:
- The window is operable;
- The window replacement includes replacement of the sash and the frame;
- 3.1. In Group R-2 or R-3 buildings containing dwelling units, the top of the sill of the window opening is at a height less than 36 inches (915 mm) above the finished floor; or
- 3.2. In one- and two-family dwellings and townhouses regulated by the Florida Building Code, Residential, the top sill of the window opening is at a height less than 24 inches (610 mm) above the finished floor;
- The window will permit openings that will allow passage of a 4-inch-diameter (102 mm) sphere when the window is in its largest opened position; and
- The vertical distance from the top of the sill of the window opening to the finished grade or other surface below, on the exterior of the building, is greater than 72 inches (1829 mm).
The window opening control device, after operation to release the control device allowing the window to fully open, shall not reduce the minimum net clear opening area of the window unit to less than the area required by the Florida Building Code, Building.
- Operable windows where the top of the sill of the window opening is located more than 75 feet (22 860 mm) above the finished grade or other surface below, on the exterior of the room, space or building, and that are provided with window fall prevention devices that comply with ASTM F2006.
- Operable windows with openings that are provided with window fall prevention devices that comply with ASTM F2090.
Where windows are required to provide emergency escape and rescue openings in Group R-2 and R-3 occupancies and one- and two-family dwellings and townhouses regulated by the Florida Building Code, Residential, replacement windows shall be exempt from the requirements of Sections 1030.2, 1030.3 and 1030.5 of the Florida Building Code, Building and Sections R310.21 and R310.2.3 of the Florida Building Code, Residential accordingly, provided the replacement window is the manufacturer's largest standard size window that will fit within the existing frame or existing rough opening. The replacement window shall be permitted to be of the same operating style as the existing window or a style that provides for an equal or greater window opening area than the existing window.
Window opening control devices complying with ASTM F2090 shall be permitted for use on windows required to provide emergency escape and rescue openings.
- All of Chapter 3, entitled "General Regulations," except Sections 303.7 and 306.
- 2.1. Sections 401.8 and 402.3 shall apply when the work being performed increases the load on the system such that the existing pipe does not meet the size required by code. Existing systems that are modified shall not require resizing as long as the load on the system is not increased and the system length is not increased even if the altered system does not meet code minimums.
- All of Chapter 5, entitled "Chimneys and Vents."
- All of Chapter 6, entitled "Specific Appliances."
Materials and methods of application used for recovering or replacing an existing roof covering shall comply with the requirements of Chapter 15 of the Florida Building Code, Building, or Chapter 9 of the Florida Building Code, Residential. Roof repairs to existing roofs and roof coverings shall comply with the provisions of this code.
Exception: Reroofing shall not be required to meet the minimum design slope requirement of one-quarter unit vertical in 12 units horizontal (2-percent slope) in Section 1507 of the Florida Building Code, Building for roofs that provide positive roof drainage (High-Velocity Hurricane Zones shall comply with Sections 15220.127.116.11 and 1516.2.4 of the Florida Building Code, Building).
New roof coverings shall not be installed without first removing all existing layers of roof coverings down to the roof deck where any of the following conditions occur:
- Where the existing roof or roof covering is water soaked or has deteriorated to the point that the existing roof or roof covering is not adequate as a base for additional roofing.
- Where the existing roof covering is wood shake, slate, clay, cement or asbestos-cement tile.
- Where the existing roof has two or more applications of any type of roof covering.
- When blisters exist in any roofing, unless blisters are cut or scraped open and remaining materials secured down before applying additional roofing.
- Where the existing roof is to be used for attachment for a new roof system and compliance with the securement provisions of Section 1504.1 of the Florida Building Code, Building cannot be met.
- Building and structures located within the High-Velocity Hurricane Zone shall comply with the provisions of Sections 1512 through 1525 of the Florida Building Code, Building.
- Complete and separate roofing systems, such as standing-seam metal roof systems, that are designed to transmit the roof loads directly to the building's structural system and that do not rely on existing roofs and roof coverings for support, shall not require the removal of existing roof coverings.
- The application of a new protective coating over an existing spray polyurethane foam roofing system shall be permitted without tear-off of existing roof coverings.
- Roof Coating. Application of elastomeric and or maintenance coating systems over existing asphalt shingles shall be in accordance with the shingle manufacturer's approved installation instructions.
When a roof covering on an existing sitebuilt single-family residential structure is removed and replaced, the following procedures shall be permitted to be performed by the roofing contractor:
- Roof-decking attachment shall be as required by Section 706.7.1.
- A secondary water barrier shall be provided as required by Section 706.7.2.
Exception: Single-family residential structures permitted subject to the Florida Building Code are not required to comply with this section.
For roof decking consisting of wood structural panels, fasteners and spacing required in columns 3 and 4 of Table 706.7.1.2 are deemed to comply with the requirements of Section 707.3, Florida Building Code, Existing Building for the indicated design wind speed range. Wood structural panel connections retrofitted with a two part urethane based closed cell adhesive sprayed onto the joint between the sheathing and framing members are deemed to comply with the requirements of Section 707.3, Florida Building Code, Existing Building, provided testing using the manufacturer's recommended application on panels connected with 6d smooth shank nails at no more than a 6-inch edge and 12-inch field spacing demonstrate an uplift resistance of a minimum of 200 psf.
Supplemental fasteners as required by Table 706.7.1.2 shall be ASTM F1667 classification RSRS-01 ring shank nails with the following minimum dimensions:
- 0.113-inch nominal shank diameter.
- Ring diameter a minimum of 0.010 inch over shank diameter.
- 16 to 20 rings per inch.
- A minimum 0.280-inch full round head diameter.
- Ring shank to extend a minimum of 11/2 inches from the tip of the nail.
- Minimum 23/8 inches nail length.
SUPPLEMENT FASTENERS AT PANEL EDGES AND INTERMEDIATE FRAMING
|EXISTING FASTENERS||EXISTING SPACING||Vasdc 110 MPH OR LESS SUPPLEMENTAL|
FASTENER SPACING SHALL BE NO
|Vasdc GREATER THAN 110 MPH|
SUPPLEMENTAL FASTENER SPACING
SHALL BE NO GREATER THAN
|Staples or 6d||Any||6" o.c.b||6" o.c.b|
|8d clipped head, round head,|
smooth or ring shank
|6" o.c. or less||None necessary||None necessary|
|8d clipped head, round head,|
smooth or ring shank
|Greater than 6" o.c.||6" o.c.a||6" o.c.a|
For SI: 1 inch = 25.4 mm.
- Maximum spacing determined based on existing fasteners and supplemental fasteners.
- Maximum spacing determined based on supplemental fasteners only.
- Vasd shall be determined in accordance with Section 1609.3.1 of the Florida Building Code, Building or Section R301.2.1.3 of the Florida Building Code, Residential.
A secondary water barrier shall be installed using one of the following methods when roof covering is removed and replaced:
- All joints in structural panel roof sheathing or decking shall be covered with a minimum 4 inch (102 mm) wide strip of self-adhering polymer modified bitumen tape applied directly to the sheathing or decking. The deck and self-adhering polymer modified bitumen tape shall be covered with one of the underlayment systems approved for the particular roof covering to be applied to the roof.
- The entire roof deck shall be covered with an approved asphalt impregnated 30# felt underlayment or approved synthetic underlayment installed with nails and tin-tabs in accordance with Section 1518.2, 1518.3 or 1518.4 of the Florida Building Code, Building. (No additional underlayment shall be required over the top of this sheet.) The synthetic underlayment shall be fastened in accordance with the manufacturer's recommendations.
- Underlayment shall comply with Section R905.1.1 of the Florida Building Code, Residential.
- Roof slopes < 2:12 having a continuous roof system shall be deemed to comply with Section 706.7.2 requirements for a secondary water barrier.
- Clay and concrete tile roof systems installed as required by the Florida Building Code are deemed to comply with the requirements of Section 706.7.2 for Secondary Water Barriers.
When a roof covering on an existing site-built singlefamily residential structure is removed and replaced on a building that is located in the wind-borne debris region as defined in the Florida Building Code, Building and that has an insured value of $300,000 or more or, if the building is uninsured or for which documentation of insured value is not presented, has a just valuation for the structure for purposes of ad valorem taxation of $300,000 or more:
- Roof to wall connections shall be improved as required by Section 706.8.1.
- Mandated retrofits of the roof-to-wall connection shall not be required beyond a 15 percent increase in the cost of reroofing.
Exception: Single-family residential structures permitted subject to the Florida Building Code are not required to comply with this section.
Where required by Section 706.8, the intersection of roof framing with the wall below shall provide sufficient resistance to meet the uplift loads specified in Table 706.8.1 either because of existing conditions or through retrofit measures. As an alternative to an engineered design, the prescriptive retrofit solutions provided in Sections 706.8.1.1 through 706.8.1.7 shall be accepted as meeting the mandated roof-to-wall retrofit requirements.
- Where it can be demonstrated (by code adoption date documentation and permit issuance date) that roof-to-wall connections and/or roof-tofoundation continuous load path requirements were required at the time of original construction.
- Roof-to-wall connections shall not be required unless evaluation and installation of connections at gable ends or all corners can be completed for 15 percent of the cost of roof replacement.
REQUIRED UPLIFT CAPACITIES FOR ROOF-TO-WALL CONNECTIONSa, b (POUNDS PER LINEAR FOOT)
|ROOF SPAN (feet)||OVERHANGS|
|Within 6 feet of|
|Greater than 6|
feet from buildingcorner
For SI: 1 foot = 304.8 mm; 1 pound per linear foot = 1.488 kg/m; 1 mile per hour = 0.305 m/s.
- The uplift loads are pounds per lineal foot of building length. For roof uplift connections multiply by 1.33 for framing spaced 16-inches on center and multiply by 2 for framing spaced 24-inches on center.
- The uplift loads do not account for the effects of overhangs. The magnitude of the above loads shall be increased by adding the overhang loads found in the table. The overhang loads are also based on framing spaced 12-inches on center. The overhang loads given shall be multiplied by the overhang projection and added to the roof uplift value in the table.
- For Ultimate design wind speeds, Vult, greater than 170 mph, wind uplift forces shall be determined in accordance with Florida Building Code, Residential, Section R301.2.1.1 of the Florida Building Code, Residential or ASCE 7.
- Ultimate Design Wind Speeds determined from Figure 1609.3(1) in the Florida Building Code, Building or Figure R301.2(4) in the Florida Building Code, Residential.
These provisions are not intended to limit the means for gaining access to the structural elements of the roof and wall for the purposes of retrofitting the connection. The retrofit of roof to wall connections can be made by access through the area under the eave, from above through the roof, or from the interior of the house. Methods for above access include removal of roof panels or sections thereof or removal of portions of roof paneling at selected locations large enough for access, viewing, and installing the retrofit connectors and fasteners.
Where panels or sections are removed, the removed portions shall not be reused. New paneling shall be used and fastened as in new construction.
Holes shall be deemed adequately repaired if a patch of paneling is installed with no gap greater than 1/2 inch (13 mm) between the patch and the existing sheathing and if the patch is supported using one of the following methods.
- Solid 11/2-inch lumber shall fully support the patch and shall be secured to the existing sheathing with #8 by 11/4-inch screws spaced a minimum of 3 inches (76 mm) around the perimeter with screws a minimum of 3/4 inch from the near edge of the hole. The patch shall be secured to the lumber with #8 × 11/4-inch screws spaced on a grid no greater than 6 inches by 6 inches (152 mm × 152 mm) with no fewer than 2 screws.
- Holes that extend horizontally from roof framing member to adjacent roofing framing member that are less than or equal to 7 inches (178 mm) wide along the slope of the roof shall be supported by a minimum of 2 × 4 lumber whose face is attached to each roofing framing members using a minimum of 2 each 3-inch (76 mm) long fasteners (#8 screws or 10d common nails) connecting the two. The patch shall have attached to its bottom, running horizontally, a minimum 2 × 4 either flat wise or on edge secured with #8 × 11/4-inch screws a maximum of 4 inches (102 mm) on center and no more distant from the end of the added lumber than 3 inches (76 mm). The patch shall be secured with two #8 × 11/4-inch screws to each support member.
Where addition or replacement of roofing or replacement of equipment results in additional dead loads, structural components supporting such reroofing or equipment shall comply with the gravity load requirements of the Florida Building Code, Building.
- Structural elements where the additional dead load from the roofing or equipment does not increase the force in the element by more than 5 percent.
- Buildings constructed in accordance with the Florida Building Code, Residential or the conventional light-frame construction methods of the Florida Building Code, Building and where the dead load from the roofing or equipment is not increased by more than 5 percent.
- Addition of a second layer of roof covering weighing 3 pounds per square foot (0.1437 kN/m2) or less over an existing, single layer of roof covering.
Where roofing materials are removed from more than 50 percent of the roof diaphragm or section of a building located where the ultimate design wind speed, Vult, determined in accordance with Figure 1609.3(1) of the Florida Building Code, Building, is greater than 115 mph (51 m/s), as defined in Section 1609 (the High-Velocity Hurricane Zone shall comply with Section 1620) of the Florida Building Code, Building, roof diaphragms, connections of the roof diaphragm to roof framing members, and roof-to-wall connections shall be evaluated for the wind loads specified in the Florida Building Code, Building, including wind uplift. If the diaphragms and connections in their current condition are not capable of resisting at least 75 percent of those wind loads, they shall be replaced or strengthened in accordance with the loads specified in the Florida Building Code, Building.
- This section does not apply to buildings permitted subject to the Florida Building Code.
- This section does not apply to buildings permitted subject to the 1991 Standard Building Code, or later edition, or designed to the wind loading requirements of the ASCE 7-88 or later editions, where an evaluation is performed by a registered design professional to confirm the roof diaphragm, connections of the roof diaphragm to roof framing members, and roof-to-wall connections are in compliance with the wind loading requirements of either of these standards or later editions.
- Buildings with steel or concrete moment resisting frames shall only be required to have the roof diaphragm panels and diaphragm connections to framing members evaluated for wind uplift.
- This section does not apply to site-built singlefamily dwellings. Site-built single-family dwellings shall comply with Sections 706.7 and 706.8.
- This section does not apply to buildings permitted within the HVHZ after January 1, 1994 subject to the 1994 South Florida Building Code, or later editions, or where the building's wind design is based on the wind loading requirements of ASCE 7-88 or later editions.
- Opening protection exception: For one- and twofamily dwellings constructed under codes other than the Florida Building Code and located in windborne debris regions, the replacement of garage doors and exterior doors with glazing, sliding glass doors, glass patio doors, skylights, and operable and inoperable windows within any 12-month period shall not be required to have opening protection but shall be designed for wind pressures for enclosed buildings, provided the aggregate area of the glazing in the replaced components does not exceed 25 percent of the aggregate area of the glazed openings in the dwelling or dwelling unit.
- Opening protection exception for High-Velocity Hurricane Zones: For one- and two-family dwellings constructed under codes prior to September 1, 1994 the replacement of exterior doors with glazing, sliding glass doors, glass patio doors, skylights, and operable and inoperable windows within any 12 month period shall not be required to have opening protection provided the aggregate area of the glazing in the replaced components does not exceed 25 percent of the aggregate area of the glazed openings in the dwelling or dwelling unit.
Openings in sunrooms, enclosed balconies and enclosed porches constructed under existing roofs or decks are not required to be protected, provided the space is separated from the building interior by a wall and all openings in the separating wall are protected in accordance with Section 1609.1.2 of the Florida Building Code, Building. Such spaces shall be permitted to be designed as enclosed or partially enclosed. (High-Velocity Hurricane Zones must comply with Chapter 16 of the Florida Building Code, Building.)
- Exterior balconies or porches under existing roofs or decks enclosed with screen or removable vinyl and acrylic panels complying with the Florida Building Code, Building, Section 2002.3.3 shall not be required to be protected and openings in the wall separating the unit from the balcony or porch shall not be required to be protected unless required by other provisions of this code.
- High-Velocity Hurricane Zones must comply with Chapter 16 of the Florida Building Code, Building.