[Federal Register Volume 75, Number 171 (Friday, September 3, 2010)]
[Notices]
[Pages 54131-54142]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2010-22062]


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DEPARTMENT OF ENERGY

[Docket No. EERE-2010-BT-DET-0030]
RIN 1904-AC17


Updating State Residential Building Energy Efficiency Codes

AGENCY: Office of Energy Efficiency and Renewable Energy, Department of 
Energy.

ACTION: Notice of proposed determination.

-----------------------------------------------------------------------

SUMMARY: The Department of Energy (DOE or Department) has preliminarily 
determined that the 2009 version of the International Code Council 
(ICC) International Energy Conservation Code (IECC) would achieve 
greater energy efficiency in low-rise residential buildings than the 
2006 IECC. Also, DOE has preliminarily determined that the 2006 version 
of the IECC would achieve greater energy efficiency than the 2003 IECC. 
Finally, DOE has preliminarily determined that the 2003 version of the 
IECC would not achieve greater energy efficiency than the 2000 IECC. If 
these determinations are finalized, States would be required to file 
certification statements to DOE that they have reviewed the provisions 
of their residential building code regarding energy efficiency and made 
a determination as to whether to update their code to meet or exceed 
the most recent code with an affirmative determination, the 2009 IECC. 
Additionally, this Notice provides guidance to States on how the codes 
have changed from previous versions, how to submit certifications, and 
how to request extensions of the deadline to submit certifications, 
should the preliminary determinations be adopted as final.

DATES: Comments on the preliminary determinations must be provided by 
October 4, 2010.

ADDRESSES: You may submit comments, identified by any of the following 
methods:
     Federal eRulemaking Portal: http://www.regulations.gov. 
Follow the instructions for submitting comments.
     E-mail: [email protected]. Include RIN 1904-AC17 
in the subject line of the message.
     Postal Mail: Mr. Ronald B. Majette, U.S. Department of 
Energy, Office of Energy Efficiency and Renewable Energy, Forrestal 
Building, Mail Station EE-2J, 1000 Independence Avenue, SW., 
Washington, DC 20585-0121. Please submit one signed paper original.
     Hand Delivery/Courier: Mr. Ronald B. Majette, U.S. 
Department of Energy, Federal Energy Management Program, Room 6003, 
1000 Independence Avenue, SW., Washington, DC 20585-0121.
    Instructions: All submissions must include the agency name, 
Department of Energy, and docket number, EERE-2010-BT-DET-0030, or 
Regulatory Information Number (RIN), 1904-AC17, for this rulemaking.

FOR FURTHER INFORMATION CONTACT: Mr. Ronald B. Majette, U.S. Department 
of Energy, Office of Energy Efficiency and Renewable Energy, Forrestal 
Building, Mail Station EE-2J, 1000 Independence Avenue, SW., 
Washington, DC 20585-0121, 202-586-7935. For legal issues contact Chris 
Calamita, U.S. Department of Energy, Office of the General Counsel, 
Forrestal Building, GC-72, 1000 Independence Avenue, SW., Washington, 
DC 20585, (202) 586-9507, e-mail: [email protected].

SUPPLEMENTARY INFORMATION:

I. Introduction
    A. Statutory Requirements
    B. Background
    C. DOE's Preliminary Determination Statements
II. Discussion of Changes in the 2003, 2006, and 2009 IECC
    A. 2003 IECC Compared With the 2000 IECC
    B. 2006 IECC Compared With the 2003 IECC
    C. 2009 IECC Compared With the 2006 IECC
III. Comparison of the 2009 IRC to the 2009 IECC
IV. Filing Certification Statements With DOE
    A. State Determinations
    B. Certification
    C. Request for Extensions
V. Regulatory Analysis
    A. Review Under Executive Order 12866
    B. Review Under the Regulatory Flexibility Act
    C. Review Under the National Environmental Policy Act of 1969
    D. Review Under Executive Order 13132, ``Federalism''
    E. Review Under the Unfunded Mandates Reform Act of 1995
    F. Review Under the Treasury and General Government 
Appropriations Act of 1999
    G. Review Under the Treasury and General Government 
Appropriations Act of 2001
    H. Review Under Executive Order 13211
    I. Review Under Executive Order 13175
VI. Public Participation
VII. Approval of the Office of the Secretary

I. Introduction

A. Statutory Requirements

    Title III of the Energy Conservation and Production Act, as amended 
(ECPA), establishes requirements for the Building Energy Standards 
Program. (42 U.S.C. 6831-6837) Section 304(b) of ECPA, as amended, 
provides that when the 1992 Model Energy Code, or any successor to that 
code, is revised, the Secretary of the Department of Energy must 
determine, not later than 12 months after the revision, whether the 
revised code would improve energy efficiency in residential buildings 
and must publish notice of the determination in the Federal Register. 
(42 U.S.C. 6833(a)(5)(A)) The Department, following precedent set by 
the International Code Council (ICC) and the American Society of 
Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) 
considers high-rise (greater than three stories) multifamily 
residential buildings and hotel, motel, and other transient residential 
building types of any height as commercial buildings for energy code 
purposes. Low-rise residential buildings include one- and two-family 
detached and attached buildings, duplexes, townhouses, row houses, and 
low-rise multifamily buildings (not greater than three stories) such as 
condominiums and garden apartments.
    If the Secretary determines that the revision would improve energy 
efficiency then, not later than 2 years after the date of the 
publication of the affirmative determination, each State is required to 
certify that it has compared its residential building code regarding 
energy efficiency to the revised code and made a determination whether 
it is appropriate to revise its code to meet or exceed the provisions 
of the successor code. (42 U.S.C. 6833(a)(5)(B)) State determinations 
are to be made: (1) After public notice and hearing; (2) in writing; 
(3) based upon findings included in such determination and upon 
evidence presented at the hearing; and (4) available to the public. 
(See, 42 U.S.C. 6833(a)(5)(C)) In addition, if a State determines that 
it is not appropriate to revise its residential building code, the 
State is required to submit to the Secretary, in writing, the reasons, 
which

[[Page 54132]]

are to be made available to the public. (See, 42 U.S.C. 6833(a)(5)(C))

B. Background

    The International Code Council's (ICC) International Energy 
Conservation Code (IECC) establishes national energy efficiency 
requirements for buildings. In 1997, the Council of American Building 
Officials (CABO) was incorporated into the ICC and the Model Energy 
Code (MEC) was renamed to the IECC. A previous Federal Register notice, 
59 FR 36173, July 15, 1994, announced the Secretary's determination 
that the 1993 MEC increased energy efficiency relative to the 1992 MEC 
for residential buildings. Similarly, another Federal Register notice, 
61 FR 64727, December 6, 1996, announced the Secretary's determination 
that the 1995 MEC is an improvement over the 1993 MEC. Finally, Federal 
Register notice 66 FR 1964, January 10, 2001, simultaneously announced 
the Secretary's determination that the 1998 IECC is an improvement over 
the 1995 MEC and the 2000 IECC is an improvement over the 1998 IECC.

C. DOE's Preliminary Determination Statement

2003 IECC
    The Department of Energy's review and evaluation found that there 
are not significant differences in energy efficiency between the 2003 
edition and the 2000 edition of the IECC. Although there are a few 
changes that would modestly improve the energy efficiency of 
residential buildings, there are a number of changes that reduce energy 
efficiency in certain situations. Most of the changes to the IECC 
between the 2000 and 2003 editions would not affect energy efficiency 
but rather make the code simpler and clearer for designers, builders, 
and code compliance officials to understand and use. Based on these 
findings, the Department has preliminarily concluded that the 2003 
edition of the IECC should not receive an affirmative determination 
under Section 304(b) of ECPA. The Department preliminarily concludes 
that there is a slight improvement in energy efficiency for many 
residential buildings, but this improvement is not sufficient to merit 
an affirmative determination. It should be noted that DOE is not 
concluding that the energy efficiency of the 2003 IECC less stringent 
than the 2000 IECC.
2006 IECC
    The residential portion of the 2006 IECC has been extensively 
changed from that the 2003 IECC. However, the most significant changes 
to the code between 2003 and 2006 simplify the code format rather than 
fundamentally changing the overall (national average) energy efficiency 
of the code. Multifamily buildings, which in the past have had 
separate, less stringent thermal requirements, are an exception. By 
eliminating the separate requirements, the 2006 IECC increased the 
energy efficiency of multifamily buildings.
    Although the most significant 2006 changes did not directly target 
efficiency improvements, the new format of the code does result in some 
energy efficiency differences. The requirements for any given building 
may have increased or decreased based on the specific location 
(climate) and building design. The Department has preliminarily found 
that overall the 2006 IECC has a small improvement in energy efficiency 
compared to the 2003 IECC. The Department preliminarily concludes that 
the 2006 edition of the IECC should receive an affirmative 
determination under Section 304(b) of EPCA.
2009 IECC
    The 2009 IECC has substantial revisions compared to the 2006 IECC. 
Many of these revisions appear to directly improve energy efficiency, 
and the sum results of all changes appear to result in a significant 
increase in code stringency. Therefore, the Department preliminarily 
concludes that the 2009 edition of the IECC should receive an 
affirmative determination under Section 304(b) of EPCA.

II. Discussion of Changes in the 2003, 2006, and 2009 IECC

A. 2003 IECC Compared With the 2000 IECC

    As a whole, the 2003 IECC's provisions for energy efficiency in 
residential buildings appear largely unchanged from the 2000 IECC. 
There are some changes in the code that can have a modest effect on 
energy efficiency. These are discussed below. In addition, there is a 
variety of minor changes intended to make the code more concise, more 
complete, and better organized, but not more or less stringent. For 
example, more specific requirements have been added for steel roofs/
ceilings and floors to correspond to those already in the code for 
steel walls. Another example is the relocation of the 51 pages of state 
maps from the middle of the code to the back of the code. Additionally, 
the performance path in Chapter 4 of the 2003 IECC contains a variety 
of modest improvements compared to the 2000 IECC, which creates more 
concise requirements.
Changes in the 2003 IECC That Improve Energy Efficiency
1. Increased Duct Insulation Requirements
    Duct insulation requirements generally increased in the 2003 IECC. 
The 2003 IECC requirements are shown in Table 1. These are somewhat 
difficult to compare to the 2000 IECC requirements because the latter 
are more complex, differing between ducts in unconditioned spaces and 
ducts completely exterior to the building and distinguishing 
requirements by the design temperature difference between the duct air 
and the space in which the ducts are located. The 2000 IECC 
requirements for ducts in unconditioned spaces are shown in Table 2. 
Assuming typical supply air temperatures of 55 degrees F for cooling 
and 95 degrees F for heating (for heat pumps), the 2000 IECC insulation 
requirement for supply ducts in unconditioned spaces is R-5 (minimum) 
for nearly all cases. Insulation required by the 2000 IECC for return 
ducts in unconditioned spaces will generally be R-3.3 in warmer 
climates and R-5 in colder climates.
    For the very common case of supply ducts in attics, and the case 
that is likely to have the greatest impact on energy use, the 2003 IECC 
always requires at least R-8, which exceeds the 2000 IECC's R-5 
requirement. For supply ducts in other unconditioned spaces, the 2003 
IECC's requirements exceed the 2000 IECC's requirements in all cases 
except very warm locations (less than 1500 heating degree-days), where 
the 2003 IECC requires R-4 compared to the 2000 IECC's requirement of 
R-5. Because supply ducts transport air in its hottest (or coldest) 
condition, insulation has its greatest impact on these ducts. The 2003 
IECC is almost always more stringent than the 2000 IECC for supply 
ducts. This includes all supply ducts in attics and, based on the 
distribution of population \1\, more than 80% of ducts in other 
unconditioned spaces.
---------------------------------------------------------------------------

    \1\ Estimated from USGS Population Places data that allows 
mapping of population to climate (http://geonames.usgs.gov/domestic/download_data.htm).
---------------------------------------------------------------------------

    Requirements for return ducts in attics are slightly more stringent 
in the 2003 IECC (R-4 vs R-3.3) in the warmest climates, slightly less 
stringent (R-4 vs R-5) in mid climates, and slightly more stringent (R-
6 vs R-5) in the coldest climates.

[[Page 54133]]

    Research \2\ showing the impact on heating and cooling energy use 
due to duct insulation is summarized in Table 3. Based on this 
research, the Department estimates that improved duct insulation in the 
2003 IECC will reduce heating and cooling energy use by about 1%.
---------------------------------------------------------------------------

    \2\ Triedler, B., R. Lucas, M. Modera, J. Miller. 1996. Impact 
of Residential Duct Insulation on HVAC Energy Use and Life-Cycle 
Costs to Consumers. American Society of Heating, Refrigerating, and 
Air-Conditioning Engineers.

                             Table 1--Duct Insulation Requirements in the 2003 IECC
----------------------------------------------------------------------------------------------------------------
                                              Insulation R-value (h [middot] ft2 [middot] [deg]F)/Btu
                                 -------------------------------------------------------------------------------
                                     Ducts in unconditioned attics or        Ducts in unconditioned basements,
 Annual heating degree days base             outside building              crawl spaces, and other unconditioned
            65[deg]F             ----------------------------------------                 spaces
                                                                         ---------------------------------------
                                        Supply              Return              Supply              Return
----------------------------------------------------------------------------------------------------------------
Below 1,500.....................                   8                   4                   4                   0
1,500 to 3,500..................                   8                   4                   6                   2
3,501 to 7,500..................                   8                   4                   8                   2
Above 7,500.....................                  11                   6                  11                   2
----------------------------------------------------------------------------------------------------------------


  Table 2--Insulation Requirements (R-value, h-ft2-F/Btu) for Ducts in
                  Unconditioned Spaces in the 2000 IECC
------------------------------------------------------------------------
  Design Temperature Difference
 (TD) between air temperature in
 duct and space in which duct is        Cooling             Heating
       located (degrees F)
------------------------------------------------------------------------
TD <= 15........................  None required.....  None required.
40 >= TD > 15...................  3.3...............  3.3.
TD > 40.........................  5.0...............  5.0.
------------------------------------------------------------------------


              Table 3--Heating and Cooling Energy Savings (Percent) From Increased Duct Insulation
                                         [Atlanta, Natural Gas Heating]
----------------------------------------------------------------------------------------------------------------
                                                                       Attic         Basement       Crawlspace
----------------------------------------------------------------------------------------------------------------
R-4 to R-6......................................................             2.3             1.6             1.8
R-6 to R-8......................................................             1.4             0.9             1.1
----------------------------------------------------------------------------------------------------------------

2. Minor Changes to ``Systems Analysis'' Performance Compliance Method
    There are two changes that can increase the stringency of the 
performance path in Chapter 4 of the 2003 IECC in certain cases. First, 
any house proposed to use electric resistance heating must have equal 
or lower calculated energy use than a hypothetical ``standard design'' 
that uses a more efficient electric air source heat pump. This change 
makes the performance approach much more stringent for designs that 
have electric resistance heating. However, compliance can be achieved 
for these designs using the prescriptive compliance methods in Chapters 
5 and 6, thereby bypassing the increased stringency of the performance 
path.
    Second, a provision has also been added requiring that the least 
efficient orientation in terms of energy use be assumed for a proposed 
group of residences with identical designs. Therefore, in a development 
where the same design is built on multiple lots facing various 
directions, the compliance analysis must be based on the least 
advantageous orientation. In most of the United States, this is the 
orientation that points the most window area toward a westerly 
direction, maximizing solar heat gains in summer afternoons and 
therefore increasing air conditioning energy use. Because proposed 
building designs must have a calculated annual energy use equal to or 
less than that of a home with window area equally distributed toward 
the four cardinal directions, the requirement to assume the least 
efficient orientation effectively makes the code more stringent because 
the increased energy use from the least efficient orientation must be 
offset by improved energy efficiency. This requirement in the 2003 IECC 
will have only modest average impact because it affects only the 
performance approach and identical house designs used repeatedly in a 
development.
B. Changes in the 2003 IECC That Decrease Energy Efficiency
1. Sunroom Additions
    A special set of requirements has been added to Table 502.2.5 of 
the 2003 IECC for sunroom additions having a floor area of less than 
500 ft\2\ (46.5 m\2\). Sunroom additions are permitted to have ceiling, 
wall insulation, and window U-factor requirements that are typically 
less stringent than the requirements for all other types of residential 
construction. These special requirements for sunrooms only apply to 
additions to existing dwellings, not to sunrooms that are built as part 
of a new dwelling. In the 2000 IECC, there were no special requirements 
for sunroom additions; they had to meet the same requirements as other 
residential construction. To qualify for the less stringent 
requirements in the 2003 IECC, the sunroom addition must be capable of 
being controlled as a separately heated and cooled zone. Additionally, 
new walls, doors or windows between the sunroom and the house must meet 
the envelope requirements of the IECC. Finally, the glazing area must 
exceed 40% of the gross area of the exterior walls and roof to qualify 
as a sunroom in the IECC.
    Testing with the DOE-2 simulation tool indicates that for a 500 
ft\2\ sunroom, the less stringent 2003 requirements could add about 
$200 to the annual energy costs in Chicago if the sunroom is both 
heated and cooled all year. Impacts are much smaller in Houston,

[[Page 54134]]

about $10 added energy costs. However, this increase in energy 
consumption is mitigated (on average) by several factors. First, the 
requirements apply to a very small fraction of all new residential 
construction. The Wall Street Journal Online (June 3, 2003) reports 
three billion dollars worth of sunroom construction each year, or less 
than one percent of all residential construction expenditures. But that 
fraction includes new construction as well as additions, so the 
fraction representing sunroom additions is less than 1%. Second, it is 
expected that many sunrooms will not be maintained at comfort 
conditions all year, further reducing the overall impact. Finally, 
because the 2003 IECC requires that the sunroom be thermally isolated 
from the rest of the house and that walls, windows, and doors between 
the sunroom and house meet the code's envelope requirements, the 
thermal impact when these spaces are not actively conditioned is 
negligible. Therefore, the overall impact of this reduction in 
stringency to national energy use is expected to be extremely small.
2. Climate Zone Maps
    The IECC contains prescriptive envelope requirements (insulation R-
values and glazing U-factors) in Chapter 6 and Section 502.2.4 of the 
code. In the 2000 IECC, only the heating degree-days for the city where 
the housing was to be built could be used to determine the applicable 
prescriptive envelope requirements. In the 2003 IECC, the heating 
degree-days can still be used to determine the requirements, but 
additionally the designer/builder can use the climate zones provided in 
the state maps in the IECC. For most locations, the Chapter 3 climate 
zones and heating degree-days lead to the exact same requirements. 
Using the climate zones in the maps instead of the heating degree-days 
will allow about 10% of cities nationwide to have a less stringent set 
of prescriptive requirements. However, about 20% of cities nationwide 
will have more stringent requirements when the climate zones are used 
with the prescriptive requirements. If the designer/builders select to 
use the climate zone maps in the 10% of cities where it lowers 
requirements but not in the 20% of locations where it raises 
requirements, the 2003 code effectively is less stringent. However, DOE 
believes code users will make use of the climate zone maps even in many 
of the locations where they raise requirements. It is doubtful most 
code users will go through the level of effort of determining which 
method of determining climate based requirements may give less 
stringent requirements. In fact, DOE believes most users will not even 
be aware of these differences, but will prefer the climate zone maps 
because of their simplicity. The REScheck compliance materials 
developed by the U.S. Department of Energy utilize the same heating 
degree day based requirements for both the 2000 and 2003 IECC.
3. Increased U-Factor for Skylight Replacements
    The maximum U-factor for skylight replacements in existing 
buildings (Section 502.2.5 of the IECC) is raised from a U-factor of 
0.50 to a U-factor of 0.60 for locations above 1,999 heating degree-
days. A higher U-factor reduces energy efficiency.
C. Net Impact on Energy Efficiency
    The change in the 2003 IECC that is expected to have the greatest 
impact on energy efficiency for the nation is the improved duct 
insulation because a majority of new residential buildings have ducts 
that pass through attics, crawl spaces, unheated basements and other 
spaces where the IECC requires duct insulation. The improved duct 
insulation in the 2003 IECC is estimated to save about 1% of heating 
and cooling costs.
    The ``Systems Analysis'' performance compliance method is a less 
commonly used compliance method and the modest energy savings from the 
improvements in this optional compliance method can easily be bypassed 
by choosing a different compliance method. Because this approach is 
optional, it is impossible to calculate the cumulative effect these 
code changes will have on energy efficiency. DOE believes that the 
changes to the system analysis method are insufficient to sway the 
decision on whether the determination is affirmative or not.
    The changes that reduce energy efficiency for sunroom additions and 
skylight replacements are not considered to have substantial impacts on 
national energy use as they do not apply to new buildings and only 
apply to specific types or retrofits and additions to existing 
buildings. The skylight U-factor change is only a modest reduction in 
energy efficiency and sunroom additions are a small fraction of the 
residential construction market.
    The addition of the climate zone maps in the 2003 IECC as an option 
to using city-specific heating degree-day data allows for the 
possibility of preferentially lowering thermal envelope requirements in 
about 10% of all national locations. However, it is difficult to 
exploit this change because the code user must perform relatively 
complex calculations rather than using the popular and user-friendly 
REScheck software.
    DOE preliminarily concludes the improved duct insulation will 
slightly improve energy efficiency in most houses. However, the 
reductions in energy efficiency for skylight replacements and sunroom 
additions are expected to at least partially offset these savings from 
a national energy total use perspective. The vast majority of all 
requirements in the IECC are unchanged from 2000 to 2003. For these 
reasons, DOE initially finds insufficient improvements in the 2003 to 
merit an affirmative determination.

B. 2006 IECC Compared With the 2003 IECC

    The residential portion of the IECC in general and the building 
thermal envelope (ceilings, walls, doors, windows, foundations, etc.) 
requirements in particular were completely restructured from 2003 to 
2006. This resulted in the code becoming much shorter and simpler, its 
volume reduced from 38 pages to 9 pages. The climate basis on which 
envelope requirements depend was completely reworked. The 2003 IECC has 
envelope requirements that vary continuously with heating degree-days 
(HDD),\3\ or with 17 HDD zones (geographically-defined based on 
counties, roughly following 500-HDD bins). In contrast, the 2006 IECC 
has eight geographically-defined climate zones with all borders set on 
county boundaries.
---------------------------------------------------------------------------

    \3\ Some compliance paths defined requirements based on 17 
``zones'' based on HDD ranges.
---------------------------------------------------------------------------

    A major change to envelope requirements was the combining of 
separate requirements for two building categories (one- and two-family 
dwellings, and all other low-rise residential buildings). The 2006 IECC 
requirements are the same for all low-rise residential building types, 
which has the effect of increasing the energy efficiency of the other 
low-rise buildings. Also eliminated were nine related tables that 
provided predefined packages of thermal transmittance prescriptive 
requirements (glazing, ceiling-roof, exterior wall, floor over 
unconditioned space, basement and crawl space walls, and floor slab on 
grade) for different window to wall area ratios (WWR). In their place, 
the 2006 IECC provides a single table of predefined packages of thermal

[[Page 54135]]

transmittance prescriptive requirements that do not vary with WWR.
    Table 4 shows a comparison of major prescriptive envelope 
requirements for a single-family house at a typical 15% WWR. The 
requirements for the 2003 IECC will differ from those shown in Table 4 
for other WWRs and for multifamily buildings. The 2006 IECC climate 
zones do not exactly map to the 2003 IECC zones. Table 5 shows a more 
detailed estimate of how residential construction maps from the 2006 
IECC compare to the 2003 IECC climate zones.

Table 4--Comparison of the 2003 IECC and 2006 IECC Envelope Thermal Component Prescriptive Criteria for One- and Two-Family Dwellings at 15% Window Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
      IECC climate zone                                 Maximum                                            Minimum
------------------------------                    ------------------------------------------------------------------------------------------------------
                                 Heating degree    Glazing U-factor        Ceiling R-value               Wall R-value                Floor R-value
                                      days                          ------------------------------------------------------------------------------------
     2003           2006                          ------------------
                                                    2003     2006         2003          2006          2003          2006          2003          2006
--------------------------------------------------------------------------------------------------------------------------------------------------------
 1...........  1 2             0-499.............     Any      1.20  R-13           R-30          R-11          R-13          R-11          R-13
--------------------------------------------------------------------------------------------------------------------------------------------------------
 2...........  ..............  500-999...........    0.90      0.75  R-19           R-30          R-11          R-13          R-11          R-13
ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½
 3...........  2               1,000-1,499.......    0.75      0.75  R-19           R-30          R-11          R-13          R-11          R-13
ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½
 4...........  ..............  1,500-1,999.......    0.75      0.75  R-26           R-30          R-13          R-13          R-11          R-13
--------------------------------------------------------------------------------------------------------------------------------------------------------
 5...........  ..............  2,000-2,499.......    0.65      0.65  R-30           R-30          R-13          R-13          R-11          R-19
ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½
 6...........  3               2,500-2,999.......    0.60      0.65  R-30           R-30          R-13          R-13          R-19          R-19
ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½
 7...........  ..............  3,000-3,499.......    0.55      0.65  R-30           R-30          R-13          R-13          R-19          R-19
--------------------------------------------------------------------------------------------------------------------------------------------------------
 8...........  ..............  3,500-3,999.......    0.50      0.40  R-30           R-38          R-13          R-13          R-19          R-19
ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½
 9...........  4               4,000-4,499.......    0.45      0.40  R-38           R-38          R-13          R-13          R-19          R-19
ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½
10...........  ..............  4,500-4,999.......    0.45      0.40  R-38           R-38          R-16          R-13          R-19          R-19
--------------------------------------------------------------------------------------------------------------------------------------------------------
11...........  ..............  5,000-5,499.......    0.45      0.35  R-38           R-38          R-18          R-19          R-19          R-19/30
ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½
12...........  ..............  5,500-5,999.......    0.40      0.35  R-38           R-38          R-18          R-19          R-21          R-19/30
ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½
13...........  5               6,000-6,499.......    0.35      0.35  R-38           R-38          R-18          R-19          R-21          R-19/30
ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½
14...........  ..............  6,500--6,999......    0.35      0.35  R-49           R-38          R-21          R-19          R-21          R-19/30
--------------------------------------------------------------------------------------------------------------------------------------------------------
15...........  5 6             7,000-8,499.......    0.35      0.35  R-49           R-38/49       R-21          R-19          R-21          R-21
--------------------------------------------------------------------------------------------------------------------------------------------------------
16...........  6               8,500-8,999.......    0.35      0.35  R-49           R-49          R-21          R-21          R-21          R-21
--------------------------------------------------------------------------------------------------------------------------------------------------------
17...........  7               9,000-12,999......    0.35      0.35  R-49           R-49          R-21          R-21          R-21          R-21
--------------------------------------------------------------------------------------------------------------------------------------------------------


----------------------------------------------------------------------------------------------------------------
     IECC climate zone                                                      Minimum
---------------------------                  -------------------------------------------------------------------
                             Heating degree    Basement wall   Slab perimeter R-value   Crawl space wall R-value
                                  days            R-value          and depth feet
    2003          2006                       -------------------------------------------------------------------
                                               2003    2006       2003         2006         2003         2006
----------------------------------------------------------------------------------------------------------------
 1..........  1 2           0-499...........     R-0     R-0  R-0          R-0          R-0          R-0
----------------------------------------------------------------------------------------------------------------
 2..........  ............  500-999.........     R-0     R-0  R-0          R-0          R-4          R-0
ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½
 3..........  2             1,000-1,499.....     R-0     R-0  R-0          R-0          R-5          R-0
ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½
 4..........  ............  1,500-1,999.....     R-5     R-0  R-0          R-0          R-5          R-0
----------------------------------------------------------------------------------------------------------------
 5..........  ............  2,000-2,499.....     R-5   R-10/  R-0          R-0          R-6          R-5
                                                          13
ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½
 6..........  3             2,500-2,999.....     R-6   R-10/  R-4,2        R-0          R-7          R-5
                                                          13
ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½
 7..........  ............  3,000-3,499.....     R-7   R-10/  R-4,2        R-0          R-8          R-5
                                                          13
----------------------------------------------------------------------------------------------------------------

[[Page 54136]]

 
 8..........  ............  3,500-3,999.....     R-8   R-10/  R-5,2        R-10,2       R-10         R-10
                                                          13
ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½
 9..........  4             4,000-4,499.....     R-8   R-10/  R-5,2        R-10,2       R-11         R-10
                                                          13
ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½
10..........  ............  4,500-4,999.....     R-9   R-10/  R-6,2        R-10,2       R-17         R-10
                                                          13
----------------------------------------------------------------------------------------------------------------
11..........  ............  5,000-5,499.....     R-9   R-10/  R-6,2        R-10,2       R-17         R-10
                                                          13
ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½
12..........  ............  5,500-5,999.....    R-10   R-10/  R-9,4        R-10,2       R-19         R-10
                                                          13
ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½
13..........  5             6,000-6,499.....    R-10   R-10/  R-9,4        R-10,2       R-20         R-10
                                                          13
ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½
14..........  ............  6,500-6,999.....    R-11   R-10/  R-11,4       R-10,2       R-20         R-10
                                                          13
----------------------------------------------------------------------------------------------------------------
15..........  5 6           7,000-8,499.....    R-11   R-10/  R-13,4       R-10,2       R-20         R-10
                                                          13
----------------------------------------------------------------------------------------------------------------
16..........  6             8,500-8,999.....    R-18   R-10/  R-14,4       R-10,4       R-20         R-10
                                                          13
----------------------------------------------------------------------------------------------------------------
17..........  7             9,000-12,999....    R-19   R-10/  R-18         R-10,4       R-20         R-10
                                                          13
----------------------------------------------------------------------------------------------------------------


                     Table 5--Percentage of Homes in Each 2006 IECC Climate Zone That Would Have Been in Each 2003 IECC Climate Zone
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                 2006 IECC climate zone
                                                              ------------------------------------------------------------------------------------------
                    2003 IECC climate zone                                                              4 except      5 and
                                                                    1            2            3          marine      marine 4        6          7 & 8
--------------------------------------------------------------------------------------------------------------------------------------------------------
1............................................................          100            5            0            0            0            0            0
2............................................................            0           20            0            0            0            0            0
3............................................................            0           40           22            0            0            0            0
4............................................................            0           31           10            0            0            0            0
5............................................................            0            3           18            0            0            0            0
6............................................................            0            0           28            0            0            0            0
7............................................................            0            0           16            4            0            0            0
8............................................................            0            0            6            9            0            0            0
9............................................................            0            0            0           13            1            0            0
10...........................................................            0            0            0           28            6            0            0
11...........................................................            0            0            0           41            8            0            0
12...........................................................            0            0            0            5           28            0            0
13...........................................................            0            0            0            0           31            0            0
14...........................................................            0            0            0            0           20           12            0
15...........................................................            0            0            0            0            6           81            3
16...........................................................            0            0            0            0            0            5            6
17...........................................................            0            0            0            0            0            2           85
18...........................................................            0            0            0            0            0            0            5
19...........................................................            0            0            0            0            0            0            2
--------------------------------------------------------------------------------------------------------------------------------------------------------

    The Department has conducted an analysis and has preliminarily 
found that the 2006 IECC would modestly increase energy efficiency on 
an overall national average basis. This analysis is summarized below; a 
technical support document published in conjunction with this Notice 
contains the full results. The Department stresses that this increased 
energy efficiency is based on an average across all new residential 
buildings. The analysis identified combinations of locations and 
building design where the 2006 IECC would slightly reduce energy 
efficiency; however, the analysis indicates that the reductions would 
be more than offset by cases where energy efficiency is improved.
    Table 6 provides the overall results of the comparative analysis of 
the

[[Page 54137]]

prescriptive envelope requirements of the 2006 IECC and the 2003 IECC. 
The DOE-2 energy simulation software was used to calculate these 
values. The 2006 IECC has a 1% average overall national energy savings. 
The table shows combined results for single-family and multifamily 
construction accounting for weighted average building characteristics. 
Table 6 illustrates significant regional differences that are primarily 
a result of the revised climate zones. In most climates, the two codes 
are very nearly equivalent. In climate zone 5, the 2006 IECC shows a 
substantial improvement (about 5%). In climate zone 3, the 2003 IECC is 
more energy efficient (by about 5%).

   Table 6--Annual Energy Savings (MBtu) of 2006 IECC Compared to 2003 IECC for Prescriptive Building Envelope
                                                  Requirements
----------------------------------------------------------------------------------------------------------------
                                                      Foundation type
                                   ----------------------------------------------------                Percent
      2006 IECC Climate zone           Heated                   Slab-on-     Unheated     Average      savings
                                      basement   Crawl space     grade       basement
----------------------------------------------------------------------------------------------------------------
Zone 1............................          0.5          0.4          0.3          0.4          0.3            2
Zone 2............................         -0.1          1.4          0.9         -0.1          0.9            3
Zone 3............................         -8.6           -1         -3.3         -1.5         -3.4           -5
Zone 4............................            2          0.8          0.6          0.7          1.1            1
Zone 5............................          5.5          7.3          4.2          6.3          5.7            5
Zone 6............................          1.1          3.3            0          2.3          1.4            1
Zone 7............................           -2          4.5          0.4          3.4         -0.4            0
Average...........................          2.4          2.7         -0.3          3.3            1            1
----------------------------------------------------------------------------------------------------------------

    The analysis underlying the results in Table 6 does not account for 
all changes in the IECC from 2003 to 2006. For example, the 2006 IECC 
requires increased duct insulation in certain cases. On the other hand, 
the 2006 IECC is missing requirements for pool heater controls (on-off 
switch) and pool covers contained in the 2003 IECC. However, these and 
a few other miscellaneous changes do not appear to alter a 
determination that the 2006 IECC has a modest improvement in overall 
energy efficiency compared to the 2003 IECC. The Department expects all 
heated pools to have an on-off switch, basic pool covers are dependent 
on the diligent occupant behavior for removing/covering the pool, and 
many homes do not have a pool or may not heat their pool. Furthermore, 
the 2003 IECC allows the pool cover requirement to be bypassed if 20% 
of the heating energy is provided by solar heat from the sun striking 
the pool surface.
    There was one particular issue that received the most extensive 
debate during the 2006 IECC development process. This issue was how the 
2006 IECC sets requirements based on the window area of a home. There 
was considerable concern because a residential building with unlimited 
windows (e.g., an ``all glass'' house) can be built without any penalty 
under the 2006 IECC. This is not the case in the 2003 IECC, where, as 
the WWR becomes higher, the code requires improved performance of 
windows and/or wall insulation. However, this effect is offset in two 
ways. First, while the 2003 IECC becomes more stringent at high WWRs, 
it also becomes less stringent at low WWRs, whereas the 2006 IECC does 
not. Second, the 2006 IECC increased the baseline efficiency 
requirements (U-factor) of glazing to almost equal then-current Energy 
Star levels in most locations. The Department's analysis of the IECC's 
requirements related to window area indicate that the 2006 code is not 
weaker than the 2003 IECC when the distribution of window areas in all 
residential buildings is accounted for.
    A major factor influencing the Department's preliminary 
determination of improved efficiency in the 2006 IECC is the 
improvement in energy efficiency for multifamily housing. The building 
envelope requirements in 2006 IECC are identical for all residential 
building types. This is not the case in the 2003 IECC where the 
requirements for multifamily building types are considerably less 
stringent than those for one and two-family dwellings. This is shown in 
the wall requirements in Figure 502.2(1) of the 2003 IECC. While 
multifamily residential construction has a much smaller market share 
than single-family in terms of number of dwelling units, there is a 
nearly universal improvement in requirements for multifamily buildings 
regardless of building design or climate zone. As indicated below in 
the certification discussion, high-rise (greater than three stories) 
multifamily residential buildings and hotel, motel, and other transient 
residential building types of any height as commercial buildings for 
energy code purposes. However, the building envelope revisions in 2006 
IECC would impact residential buildings such as townhouses, row houses, 
and low-rise multifamily buildings (not greater than three stories) 
such as condominiums and garden apartments.

C. 2009 IECC Compared With the 2006 IECC

    Each of the major changes in the 2009 IECC that impact energy 
efficiency is examined individually below. All but one of the changes 
appear to improve energy efficiency.
1. Changes That Improve Energy Efficiency
Lighting
    The 2009 IECC has a major new requirement that a minimum of 50% of 
all lamps (bulbs, tubes, etc.) be ``high efficacy,'' which is defined 
to include compact fluorescent lights (CFLs), T-8 or smaller diameter 
fluorescent tubes, or other products achieving comparable or better 
lumen-per-watt ratings. Traditional incandescent bulbs do not meet this 
requirement. The 2006 IECC had no lighting requirements for residential 
buildings. The Department estimates that lighting consumed 11.6% of all 
primary energy use in residential buildings in 2006 and that the 
requirement in the 2009 IECC could reduce lighting energy use by about 
25%.
Building Envelope Thermal Measures
    The 2009 IECC has a number of changes that improve energy 
efficiency in the building envelope. There are direct increases in 
prescriptive building envelope requirements in Tables 402.1.1 and 
402.1.3 of the IECC. Table 7 shows these changes. Additionally, there 
were a number of minor improvements, including establishing an area 
limit of 24 ft\2\ on the door exemption from U-factor requirements.

[[Page 54138]]



       Table 7--Improvements in Prescriptive Envelope Requirements
------------------------------------------------------------------------
            Component                  2006 IECC           2009 IECC
------------------------------------------------------------------------
Maximum fenestration U-factor     Zone 2: 0.75......  Zone 2: 0.65.
 (excluding skylights).           Zone 3: 0.65......  Zone 3: 0.50.
                                  Zone 4: 0.40......  Zone 4: 0.35.
Maximum fenestration solar heat   0.40..............  0.30.
 gain coefficient (SHGC) in
 Zones 1 through 3.
Basement wall insulation in       R-13 cavity or R-   R-19 cavity or R-
 Zones 6 through 8.                10 continuous       15 continuous
                                   insulation.         insulation.
Basement wall insulation in       No insulation       R-13 cavity or R-5
 northern section of Zone 3.       required.           continuous
                                                       insulation.
Wood-Frame wall insulation (all   R-19..............  R-20.
 but basements) in Zones 5 and 6.
Floor insulation in Zones 7 and   R-30..............  R-38.
 8.
------------------------------------------------------------------------

Building Envelope Air Leakage
    Although the fundamental requirement to seal all potential sources 
of leaks has not changed, the air leakage control specifications in 
Section 402.4 of the 2009 IECC are considerably more detailed than in 
the 2006 edition, requiring either a comprehensive inspection against a 
checklist of component sealing criteria or a whole-building 
pressurization test. There is a new requirement that fireplaces have 
gasketed doors to limit air leakage. Additionally, compliance with 
Standard ASTM E283 is now required to limit air leakage through 
recessed light fixtures. The 2006 IECC only required recessed light 
fixtures to be sealed but did not require compliance with the ASTM 
standard. This testing of fixtures is expected to help eliminate energy 
consuming leaks through these fixtures, which can be a very common 
method of lighting in kitchens and other rooms in new houses.
Duct Leakage Limits and Testing Requirement
    The 2009 IECC contains a new requirement that buildings with ducts 
that pass outside the conditioned space (for example, if ducts are in 
unconditioned attics, garages or crawlspaces) have the ducts pressure 
tested and shown to have a maximum leakage rate below specified limits. 
While the 2006 IECC also requires ducts to be sealed, the addition of a 
specific leakage limit verified by a pressure test in each new home or 
retrofit is expected to substantially reduce leakage in many if not 
most cases.
    Testing of completed homes in Washington State where prescriptive 
code requirements for duct sealing apply without any testing to confirm 
compliance, ``showed no significant improvement'' over non-code 
homes.\4\ Another study from Washington State concluded: ``Comparisons 
to air leakage rates reported elsewhere for homes built before the 
implementation of the 1991 WSEC show no significant improvement by the 
general population'' despite years of training emphasizing duct 
sealing.\5\
---------------------------------------------------------------------------

    \4\ Washington State University. 2001. Washington State Energy 
Code Duct Leakage Study Report. WSUCEEP01105. Washington State 
University Cooperative Extension Energy Program, Olympia, 
Washington.
    \5\ Hales, D., A. Gordon, and M. Lubliner. 2003. Duct Leakage in 
New Washington State Residences: Findings and Conclusions. ASHRAE 
Transactions. KC-2003-1-3.
---------------------------------------------------------------------------

    Numerous other studies around the nation show substantial duct 
leakage in new homes, including those in states with codes requiring 
duct sealing. For example, a 2001 study of 186 houses built under the 
Model Energy Code in Massachusetts reported ``serious problems were 
found in the quality of duct sealing in about 80% of these houses''.\6\ 
Pressurization tests in 22 of these houses found an average leakage to 
the outside of the house of 183 cfm, or 21.6% of the system flow, at a 
pressure of 25 Pascals.
---------------------------------------------------------------------------

    \6\ Xenergy. 2001. Impact Analysis Of The Massachusetts 1998 
Residential Energy Code Revisions. http://www.mass.gov/Eeops/docs/dps/inf/inf_bbrs_impact_analysis_final.pdf.
---------------------------------------------------------------------------

    The energy savings of improved duct sealing are very substantial. A 
California study estimated a sales-weighted state annual average 
savings from duct sealing of 38 therms and 239 kWh for a 1761 ft \2\ 
house.\7\ This is based on an estimated 12% improvement in duct 
efficiency based on previous studies indicating a 12-15% improvement 
potential. The Department preliminarily concludes that the 2009 IECC's 
requirement that duct air leakage meet an upper limit and be verified 
by a pressure test will save significant energy compared to the 2006 
and prior editions of the IECC.
---------------------------------------------------------------------------

    \7\ Hammon, R. W., and M. P. Modera. 1999. ``Improving the 
Efficiency of Air Distribution Systems in New California Homes-
Updated Report.'' Consol. Stockton, California. http://www.energy.ca.gov/title24/ducttape/documents/IMPROVE_EFFICIENCY_RES.PDF.
---------------------------------------------------------------------------

Improvement in Other Requirements
    1. There are a number of changes to the ``simulated performance 
alternative'' compliance path in the 2009 IECC. The glazing area in the 
baseline ``standard reference design'' was reduced from a maximum of 
18% of the conditioned floor area to 15%. This results in increased 
energy efficiency for any proposed design having a glazing area of more 
than 15%. Because use of this compliance path is completely optional, 
these savings will only occur when the user chooses this compliance 
path. Another change does not directly alter code stringency in the 
performance path but may ultimately result in some energy savings is 
the removal of the option to trade high-efficiency HVAC equipment for 
reductions in other requirements in the code, such as reduced envelope 
insulation. Because building envelopes have substantially longer lives 
than HVAC and/or water heating equipment, energy savings from envelope 
improvements may persist for many more years than comparable equipment 
improvements. Also, because high-efficiency equipment is already the 
predominant choice in many markets, disallowing envelope/equipment 
trade-offs is likely to result in improved overall efficiency in many 
situations.
2. Changes That Reduce Energy Efficiency
    There is only one change in the 2009 IECC that directly reduces 
energy efficiency. Insulation requirements for many ducts outside the 
building thermal envelope are reduced from R-8 to R-6; exceptions are 
supply ducts in attics, which must still have R-8 insulation, and ducts 
in floor trusses, which retain the 2006 code's R-6 requirement.
3. Net Impact on Energy Efficiency
    The Department has conducted an energy simulation analysis of 2009 
IECC compared to the 2006 using the DOE-

[[Page 54139]]

2 simulation tool to model \8\ a two-story, single-family house with a 
crawl space foundation and a conditioned floor area of 2,400 ft.\2\ It 
was assumed that the house had 8.5-ft high ceilings, a ceiling area 
(bordering the unconditioned attic) of 1,200 ft \2\, a gross exterior 
wall area of 2,380 ft\2\, and a window area of 357 ft \2\ (15% of the 
wall area) equally oriented north, south, east, and west. Heating with 
a natural gas furnace ($1.20/therm) and central electric air 
conditioning ($.12/kWh) were assumed.
---------------------------------------------------------------------------

    \8\ The DOE-2 simulation tool is available at http://doe2.com/.
---------------------------------------------------------------------------

    High-efficacy lighting was assumed to increase from 10% to 50% of 
all lighting within the building, reducing lighting energy use by 26%, 
or $74 a year. Savings attributable to the lighting requirements in the 
IECC will decrease as Federal law requires improved light bulbs in 2012 
to 2014. Improved duct sealing was assumed to save 10% of the heating 
and cooling costs. Figure 1 shows the estimated annual energy cost 
savings resulting from the 2009 IECC changes for 14 diverse climates 
and for the national average. Actual savings will vary depending on 
many factors, including how well ducts are currently sealed in the 
absence of any testing requirements.
[GRAPHIC] [TIFF OMITTED] TN03SE10.000

III. Comparison of the 2009 IRC to the 2009 IECC

    In the past some states have adopted the 2009 International 
Residential Code (IRC) in lieu of the 2009 IECC because the IRC 
provides a comprehensive building construction code (structural, 
plumbing, electrical, energy, etc.) in a single book for one- and two-
family dwellings and townhouses. Consequently, DOE anticipates that 
some states may wish to adopt the 2009 IRC in lieu of the 2009 IECC. In 
order to provide technical assistance to States that may wish to adopt 
the 2009 IRC, DOE has evaluated the 2009 IRC to compare the stringency 
of its energy provisions with those of the 2009 IECC. Our analysis 
indicates that the 2009 IRC would not equal or exceed the energy 
efficiency of the 2009 IECC.
    Chapter 11 of the IRC contains energy efficiency provisions. The 
IRC allows compliance with the IECC as an alternative to complying with 
Chapter 11. Most of the energy efficiency requirements in the IRC and 
IECC are identical. However, there are several differences between the 
two codes that result in the 2009 IRC having reduced energy efficiency 
compared to the 2009 IECC. All the differences are listed below.
    1. The 2009 IECC requires a glazed fenestration solar heat gain 
coefficient (SHGC) of 0.30 or lower whereas the 2009 IRC requires a 
higher (less stringent) SHGC of 0.35 or lower, in climate zones 1, 2, 
and 3. Further, the 2009 IRC allows impact resistant fenestration in 
zones 1 through 3 to meet an even less stringent SHGC requirement of 
0.40 and less stringent U-factor requirements in zones 2 and 3.
    2. For basement walls, the 2009 IECC requires either R-15 
continuous insulation or R-19 cavity insulation in zones 6-8, whereas 
the 2009 IRC requires lower (less stringent) R-values in these zones: 
R-10 continuous or R-15 cavity.
    3. The 2009 IECC requires R-38 floors in zones 7 and 8; the 2009 
IRC requires only R-30.

[[Page 54140]]

    4. The 2009 IECC limits the allowance for R-30 insulation in 
ceilings without attics to 500 ft\2\ or 20% of the total insulated 
ceiling area, whichever is less. The 2009 IRC limits the allowance to 
500 ft\2\ without regard to the total ceiling area. Thus, under the 
2009 IRC some smaller homes will have less efficient ceilings.
    The 2009 IRC differs from the 2009 IECC in some ways that, although 
they do not reduce the stringency of code requirements, have the 
potential to result in increased energy consumption in certain 
situations:
    1. Both the IRC and IECC allow for ``trade-offs'' by which the 
efficiency of one building component can be lowered in trade for higher 
efficiency in another. The 2009 IECC limits the extent to which glazing 
properties can be reduced in such trade-offs. The 2009 IECC sets a 
trade-off ``cap'' on SHGC at a maximum of 0.50 in climate zones 1, 2, 
and 3 and a cap on U-factor trade-offs of U-0.48 in zones 4 and 5 and 
U-0.40 in zones 6, 7, and 8. These caps are not present in the 2009 
IRC. As these caps do not increase stringency of the code (but rather 
restrict trade-off options), there is no direct impact on annual energy 
consumption or cost. There may, however, be some impacts on occupant 
comfort and/or resistance to moisture condensation, either of which 
could possibly induce occupants to increase energy consumption, for 
example by raising thermostat set points.
    2. The air barrier and insulation inspection requirements differ 
slightly between the codes. The 2009 IECC requires checking that ``Air-
permeable insulation is inside of an air barrier'' (right column in the 
first row). The 2009 IRC is missing this, which could result in 
insulation on the exterior side of an air barrier being exposed to 
wind-induced air movement that reduces its effective R-value.
    3. The definitions of ``conditioned space'' are different between 
the two codes, which, depending on local officials' interpretations, 
could result in different portions of a building being deemed 
conditioned and hence subject to the code's envelope requirements.
    4. The three labels ``mandatory,'' ``prescriptive,'' and 
``performance'' are used to label many sections in the 2009 IECC, but 
are not used at all in the 2009 IRC. The provisions that are mandatory 
are always required while prescriptive provisions can be traded off as 
long as overall home energy efficiency is not decreased. Thus the 2009 
IRC may permit trading down the efficiency of some components with the 
potential to induce increased energy consumption as described above.
    5. The 2009 IRC (section N1101.1, ``Scope'') states that Chapter 11 
(Energy Efficiency) does not apply to portions of the building envelope 
that do not enclose conditioned space. Section 101.5.2 of the IECC is 
more specific, exempting only building thermal envelope provisions that 
do not contain conditioned space.
Impact of the Differences Between the 2009 IRC and 2009 IECC
    The Department of Energy has performed a limited analysis of 
potential impact of the differences between the 2009 IECC and 2009 IRC. 
The analysis involves thermal simulation of home performance in several 
representative locations using the EnergyGauge (DOE-2) \9\ simulation 
tool on a typical house:
---------------------------------------------------------------------------

    \9\ EnergyGauge is available at http://doe2.com/.
---------------------------------------------------------------------------

     2400 ft\2\ floor area, two-story
     Natural gas furnace heating at $1.20/therm
     Central air conditioning electricity at 12 cents/kWh
     Equipment efficiencies at Federal minimum levels
     360 ft\2\ window area equally distributed to the north, 
east, south, and west building faces, with no exterior shading.

The results are shown in Tables 8 through 10. The 2009 IRC yields a 
higher annual energy cost in almost all cases.

          Table 8--Energy Savings of Reducing SHGC From 0.35 to 0.30 in Climate Zones One Through Three
----------------------------------------------------------------------------------------------------------------
                                                                             Cooling      Heating       Energy
               Climate zone                      Representative city         savings      increase     savings
----------------------------------------------------------------------------------------------------------------
1.........................................  Miami........................          $29           $0          $29
2.........................................  Houston......................           18            9            9
2.........................................  Phoenix......................           20            1           19
3.........................................  Atlanta......................           16           18           -2
3.........................................  Jackson MS...................           19           15            4
3.........................................  Memphis......................           17           17            0
3.........................................  Dallas.......................           20           14            6
3.........................................  El Paso......................           18           17            1
3.........................................  Las Vegas....................           16           15            1
----------------------------------------------------------------------------------------------------------------


Table 9--Energy Savings of Increasing Basement Wall Insulation From R-13
               to R-19 in Climate Zones Six Through Eight
------------------------------------------------------------------------
                                                                Energy
            Climate zone               Representative city     savings
------------------------------------------------------------------------
6..................................  Burlington............          $29
7..................................  Duluth................           34
8..................................  Fairbanks.............           33
------------------------------------------------------------------------


[[Page 54141]]


 Table 10--Energy Savings of Increasing Floor Insulation From R-30 to R-
                   38 in Climate Zones Seven and Eight
                     [Floor over unheated basement]
------------------------------------------------------------------------
                                                                Energy
            Climate zone               Representative city     savings
------------------------------------------------------------------------
7..................................  Duluth................          $13
8..................................  Fairbanks.............           19
------------------------------------------------------------------------

IV. Filing Certification Statements With DOE

A. State Determinations

    If today's determinations are finalized, each State would be 
required to determine the appropriateness of revising the portion of 
its residential building code regarding energy efficiency to meet or 
exceed the provisions of the ICC International Energy Conservation 
Code, 2009 edition. (42 U.S.C. 6833(a)(5)(B)) A State determination for 
the 2009 IECC would be sufficient to address all of the DOE 
determinations in this notice. Note that the applicability of any State 
revisions to new or existing buildings would be governed by the State 
building codes. However, it is our understanding that generally, the 
revisions would not apply to existing buildings unless they are 
undergoing a change that requires a building permit. The determinations 
would be required to be made not later than two years from the date of 
notice final determination, unless an extension is provided. The State 
determination must be: (1) Made after public notice and hearing; (2) in 
writing; (3) based upon findings and upon the evidence presented at the 
hearing; and (4) made available to the public. States have considerable 
discretion with regard to the hearing procedures they use, subject to 
providing an adequate opportunity for members of the public to be heard 
and to present relevant information. The Department recommends 
publication of any notice of public hearing in a newspaper of general 
circulation.
    Section 304(a)(4) of ECPA, as amended, requires that if a State 
makes a determination that it is not appropriate to revise the energy 
efficiency provisions of its residential building code, the State must 
submit to the Secretary, in writing, the reasons for this determination 
and the statement shall be available to the public. (42 U.S.C. 
6833(a)(4))
    States should be aware that the Department considers high-rise 
(greater than three stories) multifamily residential buildings and 
hotel, motel, and other transient residential building types of any 
height as commercial buildings for energy code purposes. Residential 
buildings include one- and two-family detached and attached buildings, 
duplexes, townhouses, row houses, and low-rise multifamily buildings 
(not greater than three stories) such as condominiums and garden 
apartments.
    States should also be aware that the determinations do not apply to 
Chapter 5 of the 2009 IECC, which addresses commercial buildings as 
defined above. Therefore, States must certify their evaluations of 
their State building codes for residential buildings with respect to 
all provisions of the IECC except for those chapters.

B. Requests for Extensions To Certify

    Section 304(c) of ECPA, as amended, requires that the Secretary 
permit an extension of the deadline for complying with the 
certification requirements described above, if a State can demonstrate 
that it has made a good faith effort to comply with such requirements 
and that it has made significant progress toward meeting its 
certification obligations. (42 U.S.C. 6833(c)) Such demonstrations 
could include one or more of the following: (1) A plan for response to 
the requirements stated in Section 304, or (2) a statement that the 
State has appropriated or requested funds (within State funding 
procedures) to implement a plan that would respond to the requirements 
of Section 304 of ECPA.

V. Regulatory Analysis

A. Review Under Executive Order 12866

    Today's action is a significant regulatory action under section 
3(f)(1) of Executive Order 12866, ``Regulatory Planning and Review'' 
(58 FR 51735; October 4, 1993). Accordingly, today's action was 
reviewed by the Office of Information and Regulatory Affairs (OIRA) in 
the Office of Management and Budget (OMB).

B. Review Under the Regulatory Flexibility Act

    The Regulatory Flexibility Act (5 U.S.C. 601 et seq.) requires the 
preparation of an initial regulatory flexibility analysis for any rule 
that by law must be proposed for public comment, unless the agency 
certifies that the rule, if promulgated, will not have a significant 
economic impact on a substantial number of small entities. As required 
by Executive Order 13272, ``Proper Consideration of Small Entities in 
Agency Rulemaking,'' (67 FR 53461; August 16, 2002), DOE published 
procedures and policies on February 19, 2003, to ensure that the 
potential impacts of its rules on small entities are properly 
considered during the rulemaking process (68 FR 7990). DOE has made its 
procedures and policies available on the Office of General Counsel's 
Web site: http://www.gc.doe.gov. Today's action on the determination of 
improved energy efficiency between IECC editions would require States 
to undertake an analysis of their respective building codes. Today's 
action does not impact small entities. Therefore, we certify that there 
is no significant economic impact on a substantial number of small 
entities.

C. Review Under the National Environmental Policy Act of 1969

    DOE has preliminarily determined that today's action is covered 
under the Categorical Exclusion found in DOE's National Environmental 
Policy Act regulations at paragraph A.6. of Appendix A to subpart D, 10 
CFR part 1021. That Categorical Exclusion applies to actions that are 
strictly procedural, such as rulemaking establishing the administration 
of grants. Today's action impacts whether States must perform an 
evaluation of State building codes. The action would not have direct 
environmental impacts. Accordingly, DOE has not prepared an 
environmental assessment or an environmental impact statement.

D. Review Under Executive Order 13132, ``Federalism''

    Executive Order 13132, 64 FR 43255 (August 4, 1999), imposes 
certain requirements on agencies formulating and implementing policies 
or regulations that preempt State law or that have federalism 
implications. Agencies are required to examine the constitutional and 
statutory authority supporting any action that would limit the 
policymaking discretion of the

[[Page 54142]]

States and carefully assess the necessity for such actions. DOE has 
examined today's action and has determined that it will not preempt 
State law and will not have a substantial direct effect on the States, 
on the relationship between the national government and the States, or 
on the distribution of power and responsibilities among the various 
levels of government. Today's action impacts whether States must 
perform an evaluation of State building codes. No further action is 
required by Executive Order 13132.

E. Review Under the Unfunded Mandates Reform Act of 1995

    The Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4) generally 
requires Federal agencies to examine closely the impacts of regulatory 
actions on State, local, and tribal governments. Subsection 101(5) of 
Title I of that law defines a Federal intergovernmental mandate to 
include any regulation that would impose upon State, local, or tribal 
governments an enforceable duty, except a condition of Federal 
assistance or a duty arising from participating in a voluntary Federal 
program. Title II of that law requires each Federal agency to assess 
the effects of Federal regulatory actions on State, local, and tribal 
governments, in the aggregate, or to the private sector, other than to 
the extent such actions merely incorporate requirements specifically 
set forth in a statute. Section 202 of that title requires a Federal 
agency to perform a detailed assessment of the anticipated costs and 
benefits of any rule that includes a Federal mandate which may result 
in costs to State, local, or tribal governments, or to the private 
sector, of $100 million or more. Section 204 of that title requires 
each agency that proposes a rule containing a significant Federal 
intergovernmental mandate to develop an effective process for obtaining 
meaningful and timely input from elected officers of State, local, and 
tribal governments.
    Today's action impacts whether States must perform an evaluation of 
State building codes. Today's action would not impose a Federal mandate 
on State, local or tribal governments, and it would not result in the 
expenditure by State, local, and tribal governments in the aggregate, 
or by the private sector, of $100 million or more in any one year. 
Accordingly, no assessment or analysis is required under the Unfunded 
Mandates Reform Act of 1995.

F. Review Under the Treasury and General Government Appropriations Act 
of 1999

    Section 654 of the Treasury and General Government Appropriations 
Act of 1999 (Pub. L. 105-277) requires Federal agencies to issue a 
Family Policymaking Assessment for any rule that may affect family 
well-being. Today's action would not have any impact on the autonomy or 
integrity of the family as an institution. Accordingly, DOE has 
concluded that it is not necessary to prepare a Family Policymaking 
Assessment.

G. Review Under the Treasury and General Government Appropriations Act 
of 2001

    Section 515 of the Treasury and General Government Appropriations 
Act, 2001 (44 U.S.C. 3516, note) provides for agencies to review most 
disseminations of information to the public under guidelines 
established by each agency pursuant to general guidelines issued by 
OMB. OMB's guidelines were published at 67 FR 8452 (February 22, 2002), 
and DOE's guidelines were published at 67 FR 62446 (October 7, 2002). 
DOE has reviewed today's action under the OMB and DOE guidelines and 
has concluded that it is consistent with applicable policies in those 
guidelines.

H. Review Under Executive Order 13211

    Executive Order 13211, ''Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use,'' 66 FR 28355 
(May 22, 2001), requires Federal agencies to prepare and submit to the 
OMB a Statement of Energy Effects for any proposed significant energy 
action. A ``significant energy action'' is defined as any action by an 
agency that promulgated or is expected to lead to promulgation of a 
final rule, and that: (1) Is a significant regulatory action under 
Executive Order 12866, or any successor order; and (2) is likely to 
have a significant adverse effect on the supply, distribution, or use 
of energy, or (3) is designated by the Administrator of the Office of 
Information and Regulatory Affairs (OIRA) as a significant energy 
action. For any proposed significant energy action, the agency must 
give a detailed statement of any adverse effects on energy supply, 
distribution, or use, should the proposal be implemented, and of 
reasonable alternatives to the action and their expected benefits on 
energy supply, distribution, and use.
    Today's action would not have a significant adverse effect on the 
supply, distribution, or use of energy and is therefore not a 
significant energy action. Accordingly, DOE has not prepared a 
Statement of Energy Effects.

I. Review Under Executive Order 13175

    Executive Order 13175. ``Consultation and Coordination with Indian 
tribal Governments'' (65 FR 67249; November 9, 2000), requires DOE to 
develop an accountable process to ensure ``meaningful and timely input 
by tribal officials in the development of regulatory policies that have 
tribal implications.'' ``Policies that have tribal implications'' 
refers to regulations that have ``substantial direct effects on one or 
more Indian tribes, on the relationship between the Federal Government 
and Indian tribes, or on the distribution of power and responsibilities 
between the Federal Government and Indian tribes.'' Today's regulatory 
action is not a policy that has ``tribal implications'' under Executive 
Order 13175. DOE has reviewed today's action under Executive Order 
13175 and has determined that it is consistent with applicable policies 
of that Executive Order.

VI. Public Participation

    The public is invited to submit comments on the preliminary 
determinations. Comments must be provided by October 4, 2010 using any 
of the methods described in the ADDRESSES section of this notice. If 
you submit information that you believe to be exempt by law from public 
disclosure, you should submit one complete copy, as well as one copy 
from which the information claimed to be exempt by law from public 
disclosure has been deleted. DOE is responsible for the final 
determination with regard to disclosure or nondisclosure of the 
information and for treating it accordingly under the DOE Freedom of 
Information regulations at 10 CFR 1004.11.

VII. Approval of the Office of the Secretary

    The Secretary of Energy has approved publication of these 
preliminary determinations.

    Issued in Washington, DC, on August 26, 2010.
Cathy Zoi,
Assistant Secretary, Energy Efficiency and Renewable Energy.
[FR Doc. 2010-22062 Filed 9-2-10; 8:45 am]
BILLING CODE 6450-01-P