Declaratory Statement DS 2012-81

ISSUE: DS 2012-81. Petitioner seeks a Declaratory Statement regarding the applicability of the 2010 Florida Building Code to enclosures/buildings proposed as protection products for electrical generating sets. The specific situations are outlined below.

Background

Florida Statutes

553.844 Windstorm loss mitigation; requirements for roofs and opening protection.—

(4) Notwithstanding the provisions of this section, exposed mechanical equipment or appliances fastened to a roof or installed on the ground in compliance with the code using rated stands, platforms, curbs, slabs, or other means are deemed to comply with the wind resistance requirements of the 2007 Florida Building Code, as amended. Further support or enclosure of such mechanical equipment or appliances is not required by a state or local official having authority to enforce the Florida Building Code. This subsection expires on the effective date of the 2013 Florida Building Code.

^{Florida Statutes}

553.73 Florida Building Code.—

(6) The initial adoption of, and any subsequent update or amendment to, the Florida Building Code by the commission is deemed adopted for use statewide without adoptions by local government. For a building permit for which an application is submitted prior to the effective date of the Florida Building Code, the state minimum building code in effect in the permitting jurisdiction on the date of the application governs the permitted work for the life of the permit and any extension granted to the permit.

SECTION 419 HOSPITALS

419.4.2.6 Heating, ventilation and air-conditioning (HVAC) standards.

419.4.2.6.1.2 Their fastening systems are designed to meet the wind load requirements of the Florida Building Code, Building and they and all associated equipment are protected as required by TAS 201, 202, and 203 in accordance with the requirements of Sections 1626.2 through 1626.4 of this code from damage by horizontal impact by a separate and independent structure that allows access to all parts of the equipment at all times or

419.4.2.6.1.3 They are completely protected by the equipment shrouding that meets the requirements of TAS 201, 202, and 203 in accordance with the requirements of Sections 1626.2 through 1626.4 of this code.

419.4.2.9.6 The emergency generator(s) shall be air or self-contained liquid cooled and it and other essential electrical equipment shall be installed in a protected area(s) designed and constructed to meet the structural requirements of the code and debris impact requirements of Sections 1626.2 through 1626.4.

SECTION 420 NURSING HOMES

420.4.2.6 Heating, ventilation and air conditioning (HVAC) standards.

420.4.2.6.1.2 Their fastening systems are designed to meet the wind load requirements of the Florida Building Code, Building and they and all associated equipment are protected as required by TAS 201, 202, and 203 in accordance with the requirements of Sections 1626.2 thru 1626.4 of this code from damage by horizontal impact by a separate and independent structure that allows access to all parts of the equipment at all times; or

420.4.2.6.1.3 They are completely protected by the equipment shrouding that meets the requirements of TAS 201, 202, and 203 in accordance with the requirements of Sections 1626.2 through 1626.4 of this code.

420.4.2.9.6 The emergency generator(s) shall be air- or self-contained liquid cooled and it and other essential electrical equipment shall be installed in a protected area(s) designed and constructed to meet the structural requirements of this code and debris impact requirements as specified by Sections 1626.2 through 1626.4.

SECTION 423 STATE REQUIREMENTS FOR EDUCATIONAL FACILITIES

423.25 Public shelter design criteria.

423.25.4.1 Missile impact criteria.

The building enclosure, including walls, roofs, glazed openings, louvers and doors, shall not be perforated or penetrated by a flying object. For walls and roofs, the missile criteria are as provided in ASTM E 1886 and ASTM E 1996, or SBC/SSTD 12.

423.25.5 Electrical and standby emergency power system.

The EHPA shall be provided with a standby emergency electrical power system, per Chapter 27, NFPA 70 Articles 700 and 701, which shall have the capability of being connected to a backup generator or other optional power source. Where economically feasible, an equivalent photovoltaic system may be provided. The EHPA’s emergency systems includes, but are not limited to: (1) an emergency lighting system, (2) illuminated exit signs, (3) fire protection system(s), alarm (campus wide) and sprinkler, and (4) minimum ventilation for health/safety purposes. The fire alarm panel shall be located in the EHPA manager’s office. A remote annunciator panel shall be located in or adjacent to the school administrator’s office. When generators are installed, the facility housing the generator, permanent or portable shall be an enclosed area designed to protect the generators from wind and missile impact. Air intakes and exhausts shall be designed and installed to meet the wind load and missile impact criteria. Generators hardened by the manufacturer to withstand the area’s design wind and missile impact criteria shall be exempt from the enclosed area criteria requirement.

SECTION 1626 HIGH-VELOCITY HURRICANE ZONES— IMPACT TESTS FOR WIND-BORNE DEBRIS

1626.1 All parts or systems of a building or structure envelope such as, but not limited to, exterior walls, roof, outside doors, skylights, glazing and glass block shall meet impact test criteria or be protected with an external protection device that meets the impact test criteria. Test procedures to determine resistance to wind-borne debris of wall cladding, outside doors, skylights, glazing, glass block, shutters and any other external protection devices shall be performed in accordance with this section.

Exception: The following structures or portion of structures shall not be required to meet the provisions of this Section:

a. Roof assemblies for screen rooms, porches, canopies, etc.; attached to a building that do not breach the exterior wall or building envelope and have no enclosed sides other than screen.

b. Soffits, soffit vents and ridge vents. Size and location of such vents shall be detailed by the designer and shall not compromise the integrity of the diaphragm boundary.

c. Vents in a garage with four or fewer cars. Size and location of such vents shall be detailed by the designer and shall not exceed the minimum required area by more than 25 percent.

d. Exterior wall or roof openings for wall- or roof-mounted HVAC equipment.

e. Openings for roof-mounted personnel access roof hatches.

f. Storage sheds that are not designed for human habitation and that have a floor area of 720 square feet (67 m2) or less are not required to comply with the mandatory windborne debris impact standards of this code.

g. Louvers as long as they properly considered ASCE 7 in the design of the building.

h. Buildings and structures for marinas, cabanas, swimming pools and greenhouses.

i. Exterior balconies or porches under existing roofs or decks enclosed with screen or removable vinyl and acrylic panels complying with Section 1622.1 or Section 1622.2 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.

1626.4 Construction assemblies deemed to comply with Section 1626.

1. Exterior concrete masonry walls of minimum nominal 8-inch (203 mm) thickness, constructed in accordance with Chapter 21 (High-Velocity Hurricane Zones) of this code.

2. Exterior frame walls or gable ends constructed in accordance with Chapter 22 and Chapter 23 (High-Velocity Hurricane Zones) of this code, sheathed with a minimum 19/32-inch (15 mm) CD exposure 1 plywood and clad with wire lath and stucco installed in accordance with Chapter 25 of this code.

3. Exterior frame walls and roofs constructed in accordance with Chapter 22 (High-Velocity Hurricane Zones) of this code sheathed with a minimum 24-gage rib deck type material and clad with an approved wall finish.

4. Exterior reinforced concrete elements constructed of solid normal weight concrete (no voids), designed in accordance with Chapter 19 (High-Velocity Hurricane Zones) of this code and having a minimum 2-in. (51 mm) thickness.

5. Roof systems constructed in accordance with Chapter 22 or Chapter 23 (High-Velocity Hurricane Zones) of this code, sheathed with a minimum 19/32-inch (15 mm) CD exposure 1 plywood or minimum nominal 1-inch (25 mm) wood decking and surfaced with an approved roof system installed in accordance with Chapter 15 of this code.

All connectors shall be specified by the building designer of record for all loads except impact.

Staff Recommendation:

1. A Client intends to install an electrical generator set in an enclosure to provide emergency backup power to a hospital in the event of a loss of utility power. There will be no other debris impact protection aside from the generator enclosure.

According to FBC 419.4.2.9.6 “The emergency generator(s) shall be air or self-contained liquid cooled and it and other essential electrical equipment shall be installed in a protected area(s) designed and constructed to meet the structural requirements of the code and debris impact requirements of Sections 1626.2 through 1626.4”.

a. Is the generator enclosure required to be tested and approved per Section 1626 of the 2010 Florida Building Code and bear either appropriate Florida Product Approval numbers or Miami-Dade Notice of Acceptance approval?

Answer: As per Section 419.4.2.9.6 of the 2010 FBC, Building “the Code”, the generator enclosure in question must be constructed to meet the structural requirements of the Code and the debris impact requirements of Sections 1626.2 through 1626.4 as applicable. Further, in order to demonstrate compliance with the debris impact requirements of the Code, the generator enclosure or its components must be either tested to TAS 201, 202, and 203 in accordance with the requirements of Sections 1626.2 and 1626.3 as applicable or designed/constructed to meet the deemed to comply standards of Section 1626.4 as applicable. Product approval of the enclosure in question as meeting the debris impact requirements of the Code is subject to the review and discretion of the authority having jurisdiction.

2. A Client intends to install an electrical generator set in an enclosure to provide emergency backup power to a Nursing Home in the event of a loss of utility power. There will be no other debris impact protection aside from the generator enclosure.

According to FBC 420.4.2.9.6 “The emergency generator(s) shall be air or self-contained liquid cooled and it and other essential electrical equipment shall be installed in a protected area(s) designed and constructed to meet the structural requirements of the code and debris impact requirements of Sections 1626.2 through 1626.4”.

Answer: As per Section 420.4.2.9.6 of the 2010 FBC, Building “the Code”, the generator enclosure in question must be constructed to meet the structural requirements of the Code and the debris impact requirements of Sections 1626.2 through 1626.4 as applicable. Further, in order to demonstrate compliance with the debris impact requirements of the Code, the generator enclosure or its components must be either tested to TAS 201, 202, and 203 in accordance with the requirements of Sections 1626.2 and 1626.3 as applicable or designed/constructed to meet the deemed to comply standards of Section 1626.4 as applicable. Product approval of the enclosure in question as meeting the debris impact requirements of the Code is subject to the review and discretion of the authority having jurisdiction.

3. A Client intends to install an electrical generator set in an enclosure to provide emergency backup power to an Enhanced Hurricane Protection Area (EHPA) as part of an Educational Facility Public Shelter in the event of a loss of utility power. There will be no other debris impact protection aside from the generator enclosure.

According to FBC 423.25.5 “When generators are installed, the facility housing the generator, permanent or portable, shall be an enclosed area designed to protect the generators from wind and missile impact. Air intakes and exhausts shall be designed and installed to meet the wind load and missile impact criteria. Generators hardened by the manufacturer to withstand the area’s design wind and missile impact criteria shall be exempt from the enclosed area criteria requirement.”

Answer: According to Section 423.25.5 of the 2010 Florida Building Code, Building (the Code); the generator enclosure or its components is required to be designed to protect the generator from wind and missile impact and thus the generator enclosure or its components must be tested and approved as meeting the impact requirements of Section 423.25.4.1 of the Code.

4. A Client intends to install an electrical generator set in an enclosure to a commercial facility located in a High Velocity Hurricane Zone (HVHZ) to provide emergency backup power in the event of a loss of utility power. The generator Set and enclosure will be installed on the roof of the facility. There will be no other debris impact protection aside from the generator enclosure.

According to FBC 1601.1 “The provisions of this chapter shall govern the structural design of buildings, structures and portions thereof regulated by this code.
Exception: Buildings and structures located within the high-velocity hurricane zone shall comply with the provisions of Sections 1615 through 1626, and, as applicable in flood hazard areas, Section 1612.”

Answer: No. According to Section 1626.1(d) of the Code, roof – mounted HVAC equipment are not required to meet the impact test criteria of Section 1626 of the Code.

5. A Client intends to install an electrical generator set in an enclosure to a commercial facility located in a High Velocity Hurricane Zone (HVHZ) to provide emergency backup power in the event of a loss of utility power. The generator Set and enclosure will be installed on the ground floor of the facility. There will be no other debris impact protection aside from the generator enclosure.

Answer: No. The electrical generator in question is not required to be protected as per Section 1626 of the Code. In fact, Section 1626 is limited in scope to the building envelop and the case in question falls outside the building envelop.