Important Code Concepts

Whole-Building Performance-based compliance.  At its heart, Florida's energy code is a whole-building, performance-based code (Method A). This means that the building as a whole, rather than its component parts, must "meet or exceed" an energy efficiency standard (an energy budget). Although prescriptive code compliance pathways are available (Methods B and C), they are based on worst-case Method A analyses and less than 10% of applicants choose to use them. This has two very important consequences:

• First, if like more than 90% of applicants, you choose Method A compliance, there are very few prescriptive standards that the individual components (walls, windows, floors, doors, etc.) of your home must meet.
  
  
• Second, with Method A you may always substitute a high-performance energy component for a low-performance energy component as long as you "meet or exceed" the overall efficiency standard ('energy budget') for your home.

The 'Baseline' Home.  Put most simply, Florida's 'baseline' home is the geometric twin of your proposed home (or the 'as-built' home) with its energy characteristics set to a given performance standard. In other words, the insulation characteristics (R-value) of the ceiling, wall, floor insulation, etc. are set to a specific value for the 'baseline' home. This 'baseline' home is then used to establish an 'energy budget' that your proposed (or your 'as-built') home must "meet or exceed." If your proposed home uses the same or less energy as the 'baseline' home then it will comply with the energy efficiency provisions of Florida's Building Code and it will be permitted for construction (assuming it complies with the other provisions — structural, electrical, plumbing, etc. — of Florida's Building Code).

It is also critically important to understand that the component performance characteristics given for the 'baseline' home are not required for your proposed ('as-built') home. In other words, 'baseline' home component performance characteristics never constitute a prescriptive requirement for the individual components of your proposed home.

What does this mean? Put very simply it means that just because the 'baseline' home requires R-11 wall insulation, it does not mean that your proposed home requires R-11 wall insulation. In fact, your proposed home can comply with the energy code with R-0 wall insulation as long as you make up for this low wall insulation value elsewhere in the home's performance.

The 2001 Code Changes

Major Changes.  With the above as background, there are significant changes to the code's 'baseline' home that will impact the required overall efficiency of proposed homes in the 2001 Florida Building Code, effective March 1, 2002. There are three major changes:

• The 'baseline' home heating system has been changed from electric strip resistance with an HSPF (Heating Season Performance Factor) of 3.4 to an electric heat pump with an HSPF of 6.8 for central and south Florida climate zones. The north Florida climate zones have always used an electric heat pump with HSPF of 6.8 for their 'baseline' home so they have not changed. This is a substantial change for the central Florida climate zone but not so much so for south Florida where heating is a very small portion of the annual 'energy budget' projected by the 'baseline' home.
  
  
• The 'baseline' home is assumed to have a "leaky" air distribution (duct) system. In previous versions of the Florida Energy Code, the 'baseline' home was assumed to have a "leak free" air distribution system. This change in the 'baseline' home allows homes with air distribution systems that are tested to be "leak free" to gain a substantial credit for their improved duct systems. (See Code Officials page for information on how to process this credit.)
  
  
• The 'baseline' home windows have been changed to account for the improved solar control that is needed in southern climates. In previous Florida codes the 'baseline' home windows had a Solar Heat Gain Coefficient of 0.61 (SHGC = the amount of solar heat that actually enters the window compared to the amount that strikes it on the outside). In the 2001 Florida Building Code, the SHGC value for the 'baseline' home windows has been reduced from 0.61 to 0.40. This is a substantial change for all of Florida's climate zones.

The above major changes were effected in order to bring the 2001 Florida Building Code into alignment with the 1998 (and 2000) International Energy Conservation Code (IECC), the prevailing federal standard for residential energy codes. This was necessary in order for Florida to be able to certify to the Secretary of the U.S. Department of Energy that Florida's residential energy code "meets or exceeds" the standards of the 1998 IECC