The new 2001 Building Code contains important changes in residential energy efficiency provisions. These changes will impact both code compliance and, to a lesser extent, Home Energy Ratings in Florida. This web page is designed to provide information on what these changes are and how they may impact residential building practice in Florida. First, however, there are some important concepts that must be explained.

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 our 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.

Other changes.  There are a number of other changes that will impact code compliance under certain circumstances:

• A method of evaluating the energy impacts of "cool roofs" has been added. This means that you will now be able to get an energy "credit" for the impact of certain white roofing products under the provisions of the 2001 Building Code.
  
  
• The impact of air handler unit (AHU) location has been modified. Air handler units that are located in attics will receive a greater energy "penalty" than in the current version of the energy code.
  
  
• The ceiling 'multipliers' for attic insulation have been modified to more accurately represent the impacts of attic heat transfer on the total heating and cooling energy use of homes.
  
  
• Interior Radiation Control Coatings (IRCC) 'multipliers' have been added to the ceiling and duct insulation 'multiplier' tables. Much like radiant barriers, IRCC are a means of reducing radiation from hot roof undersurfaces to the cooler attic ceiling insulation and attic mounted duct systems.
  
  
• A provision to give an energy "credit" for "factory-sealed air handlers" has been added.

What Does it all Mean?

Misconceptions. For one thing, as with all things new, it means that there will be misunderstanding and confusion regarding the new provisions of the 2001 Building Code. As a result, you will likely hear inaccurate and unfounded claims regarding the new 2001 Building Code, even from seemingly authoritative sources. Let's examine a few examples that have recently appeared in prominent, widely-circulated publications:

• NFRC Update Magazine.  An article entitled "Solar Heat Gain Is in the News!" that appeared in the Summer 2001 edition of this widely-read magazine states categorically that "Florida prescriptive requirements will require SHGC of 0.40 for all windows in the state effective January 2002." Nothing could be further from the truth. As clarified above, Florida's code is performance-based and there is absolutely no requirement that the characteristics of the 'baseline' home windows be used for the windows in your proposed home. The Editor of this publication has been contacted and asked to print a revision in order to avoid confusion about Florida's new residential 2001 Building Code.
  
  
• The Florida Building Code and the Florida Home Builder.  This full color brochure was distributed to attendees of the Southeastern Builders Conference (SEBC) held in Orlando in July 2001, and has since been widely distributed throughout the state. Unfortunately, this publication contains an article entitled "Energy Code" with numerous misconceptions. Many of these misconceptions alongside the respective factual code information can be viewed at SEBC brochure.

The Facts.  The simple truth of the matter is that these changes mean that Florida's 2001 Building Code is more stringent than the current energy code. On the other hand, it is also true that there are new, cost-effective opportunities for complying with the 2001 Building Code, like "cool roofs" and "leak free" air distribution systems, that do not exist in the present code provisions.

How much more stringent is the new energy code? The answer to this question depends heavily on the Florida Climate zone you are considering. The greatest overall increase in stringency occurs in central Florida and the smallest overall increase occurs in north Florida. As a general rule-of-thumb (and this will change with the design of your home), the increases in stringency for the 2001 Florida Building Code may be generally represented by the following table.

This table deserves some explanation. First, it is important to understand that the individual End Use stringency changes are not supposed to add to the Overall stringency increases. This occurs because each individual end use makes up a different percentage of total energy use, depending on climate. For example, heating energy use makes up 30% of the total in north Florida, 11% of the total in central Florida and only 3% of the total in South Florida. Of course, the opposite trend would hold for cooling energy use.

The increases in cooling stringency stem almost entirely from the fact that the SHGC for the 'baseline' home windows has been changed from 0.61 to 0.40. One further, and perhaps counterintuitive, impact of this SHGC change is the decrease in heating stringency for the north Florida climate zone. This occurs because the low SHGC 'baseline' window does not yield as much wintertime solar heat gain benefit in the 'baseline' home as does the larger SHGC that is used in the 1997 version of the energy code.

The large changes in heating stringency for central and south Florida are due entirely to the fact that the efficiency of the 'baseline' home heating equipment has been doubled. The reason that this change is not 50%, as this doubling might indicate, is the same as the reason that there was a decrease in heating stringency in north Florida — the lower window SHGC for the 'baseline' home results in less wintertime solar heat gain to the 'baseline' home.

The Bottom Line

In the final analysis, these increases in stringency for Florida's new 2001 Building Code will directly translate into energy cost saving for new home purchasers. These energy cost savings will accumulate for many decades, resulting in lower monthly costs for home ownership in Florida.

Florida home building also will change somewhat. However, these changes are unlikely to be as severe as special interests would have us believe. For example, it will still be quite possible to build code-complaint homes with single-pane, metal windows in Florida. This fact can be clearly observed in the new Method B (prescriptive) compliance packages, many of which still require only single-pane windows.

The most often overlooked aspect of Florida's new 2001 residential Building Code are its new provisions allowing builders to gain energy "credits" for very cost-effective energy features like "leak free" ducts and "cool roofs." These are efficiency features that have been shown through research to save large quantities of energy in Florida homes. In central Florida, these two features alone will garner 13-15% in energy "credits" — often enough to completely offset the increase in stringency of Florida's new 2001 Building Code.

Further Information

There are two authoritative sources of additional information on Florida's new 2001 residential Building Code:

In addition to the above resources, the 2001 Florida Building Code is available online at www.sbcci.org/floridacodes.htm (Energy is Chapter 13) and the Florida Building Commission web site may be found at www.dca.state.fl.us/fhcd/fbc/.