HVAC equipment replacement 


Duct sealing


At the time of total replacement of HVAC evaporators and condensing units, all accessible (min. 30” clearance) joints and seams in the air distribution system shall be inspected and sealed where needed;  certified by contractor.

  1. Inspection through observation.
  2. Investigation or testing is not required.
  3. Only joints and seams that are observed to need sealing (i.e. loose joints) should be sealed.



 This provision does not apply to partial replacement of equipment (i.e. where the air distribution system is not independent to the partial replacement of equipment).  An HVAC “system” includes all components connected by a joint air distribution system.



Equipment sizing calculation

An a/c contractor or licensed Florida PE shall submit a nationally recognized method based sizing calculation to the code official at the time of permit application for total replacement of the condensing and evaporator components of HVAC systems in accordance with Florida law and the provisions of Sec. 403.6.2.2 or 403.6.2.3.


1. Several “recognized” sizing calculation methods for existing buildings are available from HVAC equipment manufacturers and ACCA accredited software that are subject to approval by the code official.

2. Per Section 101.54 of the FBC-EB, original systems installed on buildings constructed under the 1993 Energy Code or later have already been sized for the building and, without changes to the building, may be assumed to have been sized per code. 

3. If a copy of a previous sizing calculation is provided, it is deemed to meet code.



This provision does not apply to partial replacement of equipment (i.e. where the air distribution system is not independent to the partial replacement of equipment).  An HVAC “system” includes all components connected by a joint air distribution system.


Duct insulation levels


Section 403.2.1 requires ducts located in attics or on roofs to be insulated to a minimum of R-8.

Tables 402.1.1 and 402.1.1.3 (Prescriptive method) require ducts to be R-6 and located in conditioned space.

Section 405.2 (Performance method) requires all supply and return ducts not completely inside the building thermal envelope to be insulated to at least R-6.

Ergo:  R-8 isn’t a minimum code requirement.

Matched indoor/outdoor units

Matched systems may be verified by one of the following means.

  1. AHRI data
  2. Accredited laboratory
  3. Letter from the equipment manufacturer
  4. Letter from registered Florida professional engineer
  5. Load sizing or duct inspection is not required

Duct testing


Replacement or extension of an existing air distribution system is not required to be tested.




Pool filtration pumps6

If cost of job exceeds 30% of assessed value of pool structure, meet Sec. 403.9.4 requirements

If cost of job does not exceed 30% of assessed value of pool structure, does not have to meet Energy Code requirements.

In general, Florida law trumps what’s in the code. Florida law has been incorporated into the FBC-Energy Conservation in Table 101.4.1.

  1. Section 553.903, Florida Statutes, Applicability, states:  “This part shall apply to all new and renovated buildings in the state, except exempted buildings, for which building permits are obtained after March 15, 1979, and to the installation or replacement of building systems and components with new products for which thermal efficiency standards are set by the Florida Energy Efficiency Code for Building Construction.” [NOTE: 2 clauses]
  2. Section 101.4.7 of the FBC-Energy Conservation, states:  “Thermal efficiency standards are set for the following building systems where new products are installed or replaced in existing building and for which a permit must be obtained. New products shall meet the minimum efficiencies allowed by this code for the following systems:  Heating, ventilating or air conditioning systems; Service water or pool heating systems; Electrical systems and motors; Lighting systems.”
  3. Section 202 of the FBC-EC defines HVAC SYSTEM as “The equipment, distribution systems, and terminals that provide, either collectively or individually, the processes of heating, ventilating, or air conditioning to a building or portion of a building.”  It further defines a SYSTEM as “A combination of equipment and auxiliary devices (e.g., controls, accessories, interconnecting means, and terminal elements) by which energy is transformed so it performs a specific function such as HVAC, service water heating, or lighting”.  Commercial buildings where the system is comprised of multiple air handlers, chillers, evaporators and/or condensers do not constitute “replacement of the building system with new products” unless the whole system is replaced.
  4. Sec.101.5, FBC-Existing Building, provides the following exception for repairs and alterations: “Subject to the approval of the code official, alterations complying with the laws in existence at the time building or the affected portion of the building was built shall be considered in compliance with the provisions of this code unless the building is undergoing more than a limited structural alteration.
  5. Sec. 553.902, Florida Statutes, defines RENOVATED BUILDING as “a residential or nonresidential building undergoing alteration that varies or changes insulation, HVAC systems, water heating systems, or exterior envelope conditions, provided the estimated cost of renovation exceeds 30 percent of the assessed value of the structure.” Section 202 of the FBC-Energy Conservation, further clarifies that the cost shall be cumulative over a 1 year period.
  6. Pool filtration pumps are not a pool heating system.
  7. An existing building or portion thereof may not be altered such that the building becomes less energy efficient than its existing condition.
  8. FORM 402 - 2010

Ducts & AHU installed substantially leak free per Section 403.2.2.1. Test by Class 1 BERS rater required.

Exception: Ducts installed onto an existing air distribution system as part of an addition or renovation; duct must be R-6 installed per Sec. 503.2.7.2