Converting Condominium Lanai to Living Space

Conversion Considerations
The conversion of a lanai to conditioned space is a common request by condominium owners, but there are several important issues to consider when attempting this:

  • Conversion usually involves the installation of glassed walls (windows) or sliding-glass doors to the outer edge of the unit.
  • There are some special considerations in regard to the protection of vertical openings in buildings that must be addressed when converting a lanai space.

Vertical Separation Requirements
If the building is three stories or less, there are no vertical separation requirements. If the building is more than three stories, but it is a sprinkled building and the sprinklers can be extended into the new conditioned space, obtaining a permit is a straightforward process.

Florida Building Code Requirements
The Florida Building Code (FBC) Section 705.8.5 is the primary code that applies in this type of work. This code section requires openings such as windows, doors and sliding-glass doors in exterior walls to be protected from fire spreading from one floor to the floor above it. Openings must be separated vertically by at least 36 inches,horizontally by 30 inches, or a one-hour fire rating or the space must be sprinkled. 

Fire Spreading
There have been a few, very tragic occurrences of fires spreading up the side of a building via unprotected openings, which resulted in a loss of life. The intent of this code is to prevent such occurrences. New buildings are designed to prevent such an occurrence. However, older, existing buildings must incorporate new design in their construction to comply with the code.

Alternative Methods of Compliance
In years past, City of Naples officials have accepted various methods of achieving this fire protection. At times, that has caused some confusion. In 2011, in an effort to standardize these methods, the city engaged the services of a licensed fire protection engineer (FPE) to research the code and recommend methods of achieving an alternative materials, design, and method of construction and equipment compliance with FBC Section 705.8.5. A detailed report from the FPE is available from the Building Department, but overall direction for compliance is provided below. Each project shall be reviewed by the department for compliance with section 705.8.5. The Building official requires per the Florida Building Codes, 5th Edition section 104.11 an alternative materials, design, and method of construction and equipment to be submitted for review for compliance with the requirements of 705.8.5. The proposed alternative design shall be provided by a Engineer licensed in the State of Florida, affixed with their seal, including all required information, tests, and reports. The Building and Fire Departments shall review the proposed design for compliance with section 705.8.5. The alternative method of compliance shall be approved where the Building Official finds that proposed design is satisfactory and complies with the intent of the provisions of the code, and that the material, method or work offered is, for the purpose intended, at least the equivalent of that prescribed by the code in quality, strength, effectiveness, fire resistance, durability and safety.

2011 Fire Protection Engineer Report
Based on the findings of the FPE, the most easily achieved means of compliance are as follows:

  1. Install impinging water-curtain sprinklers. The sprinklers should be located 2 inches to 4 inches down from the window head and within 4 inches of the glazing surface.
    • The sprinkler should discharge against and completely wet the glazing surface.
    • Any sprinkler(s) that adequately wet(s) the glazing surface should be acceptable.
    • Listed quick-response window sprinklers should be acceptable.
    • Sprinklers should be spaced one per glazing panel between deep millions but not less than 6 feet on center along the length of the water curtain.
    • Maximum distance between sprinklers should be 10 feet.
    • The sprinklers must be quick-response and should discharge a minimum of 25 gallons per minute.
    • The design area should include all sprinklers in the water curtain within a room to a maximum of four sprinklers.
    • Other elements of the sprinkler system should conform to NFPA 13.
  2. Install free-fall water-curtain sprinklers at the ceiling near the glazing at the interior side of a proposed lanai / balcony exterior wall. The pendent residential sprinklers should be located from 12 inches to 24 inches from the face of the lanai exterior-enclosing wall.
    • The sprinkler half spray should discharge against and wet most of the glazing surface.
    • Any residential or quick-response extended coverage sprinklers should be acceptable.
    • Sprinklers should be spaced one per glazing panel (between deep mullions) but no less than 8 feet on center (along the length of the water curtain).
    • Maximum distance between sprinklers should be 10 feet.
    • The sprinklers must be quick-response and should discharge a minimum of 25 GPM.
    • The design area should include all sprinklers in the water curtain within a room, to a maximum of four sprinklers.
    • Other elements of the sprinkler system should conform to National Fire Protection Act (NFPA) 13.
  3. Install sprinklers throughout the proposed enclosed lanai / balcony. The lanai-room sprinkler system should be designed per NFPA 13 for a residential occupancy, using residential sprinklers and a light-hazard density of at least 0.1 GPM per square foot.
  4. Install sprinklers throughout the dwelling-unit area. The dwelling-unit sprinkler system should be designed per NFPA 13 for a residential occupancy.

Alternatives to Sprinkler System Design
A sprinkler system design is the preferred method of compliance. However, the installation of a one-hour rated wall or a one-hour rated glass assembly is another possible design. A one-hour rated, sliding-glass door or movable window is not possible, since the one-hour protection disappears when they are opened. Most fixed, one-hour rated glass assemblies are not acceptable to the condominium associations for aesthetic reasons. 

One-Hour Rated Glass Designs
On rare occasions, our department will consider a one-hour rated glass design that has been created by a professional engineer (PE) and meets the equivalency requirement of FBC Section 104.11. The level of technical information that must be supplied by the PE in an attempt to comply with this type of design is very great, and each design presented will be reviewed for sufficiency and compliance on an individual basis. The burden of sufficiency rests with the PE, but acceptance of the design can only be made by the building official.