DOE Code Change Proposals
for the 2007/2008 ICC Code Development Cycle

The U.S. Department of Energy has submitted 17 code change proposals for the International Code Council's (ICC) 2007/2008 Code Development Cycle. The proposals pertain to the International Energy Conservation Code (IECC) and International Residential Code (IRC). There is one proposal that applies specifically to commercial buildings. All other proposals apply only to residential buildings (except item 6 below, which applies to all buildings).

DOE welcomes an open dialogue on improving energy efficiency in building codes. If you have thoughts or suggestions on DOE's proposals or on energy efficiency codes in general, please contact Ronald Majette.

Proposals Impacting Residential Buildings

1. Require verification of duct sealing by pressurization test. This would require duct systems that are not fully inside the conditioned space be tested to ensure that air leakage is below a reasonable limit. Although the code already requires that ducts be sealed, its lack of verification requirements results in a continued problem of excessive duct leakage in new residences.

   Verified duct sealing (PDF 97 KB).

2. Reduce vertical fenestration U-factor requirements from 0.65 to 0.55 in climate zone 3 and from 0.75 to 0.65 in climate zone 2. Most windows on the market today that meet the zone 2 and 3 SHGC requirement of 0.40 will also meet a U-factor requirement of 0.55. These proposed improvement in U-factor will save energy by weeding out inefficient windows and preventing excessive trade-off credit for other windows.

   U-0.55 fenestration in Zone 3 (PDF 95 KB).

   U-0.65 fenestration in Zone 2 PDF 93 KB).

3. Clarify that the 15-ft2 window and the opaque door exemptions in IECC Section 402.3 and IRC Section N1102.3 do not apply to U-factor compliance approaches. The exemptions are needed in the otherwise inflexible R-value compliance approach but are unnecessary and logically impossible to define for the already flexible U-factor compliance approach.

   Window exemption (PDF 82 KB).

4. Permit duct R-value trade-off in the IECC Section 404 performance path. This would allow duct insulation trade-offs in the performance path but put a hard limit on duct insulation to a minimum of R-4. Unlike DOE's comparable proposal last cycle, this proposal does not specify a calculation methodology.

   Duct insulation trade-off (PDF 86 KB).

5. Require basement wall insulation in the colder parts of climate zone 3 (those not designated warm-humid regions).

   Basement wall insulation (PDF 98 KB).

6. Require that mandatory IECC requirements be met even if the "above code" path in Section 103.1.1 of the IECC is used.

   Above code mandatory requirement (PDF 80 KB).

7. Reduce maximum allowable SHGC from 0.40 to 0.37 in climate zones 1 and 2 in the IRC. This would bring the IRC into agreement with IECC, where the 0.37 SHGC requirement was approved last cycle.

   0.37 SHGC (PDF 85 KB).

8. Clarify that the allowance for ceiling R-value reductions in IECC Sections 402.2.1 and 402.2.2 and IRC N1102.2.1 an N1102.2.2 do not apply to U-factor based compliance approaches.

   Ceiling R-value allowances (PDF 84 KB).

9. Remove ground conductance from foundation U-factor requirements in Table 402.1.3. This has been requested by compliance software developers.

   Foundation U-factor calculations (PDF 88 KB).

10. Modify IRC mass wall requirements to match those in the IECC, both in format and in requirements. Minor differences remain despite approval of EC34-06/07 in the IECC last cycle.

    Mass wall requirements (PDF 91 KB).

11. Expand county tables in Chapter 3 of the IECC and Chapter 11 in the IRC to list every county. This a format change for clarification only. It eliminates confusion for some code users who now have to verify that their county is NOT in the table to identify their climate zone. It also eliminates the need for a separate table listing warm-humid counties.

    County table (PDF 81 KB).
    Attachment (full table) (PDF 30 KB).

12. Clarify that heated slab insulation, when required, must be 2 feet deep in climate zones 1-3. The IECC and IRC are currently confusing on this subject as R-5 insulation is required but the required depth appears to be zero feet.

    Heated slab (PDF 88 KB).

13. Clarify that a conditioned crawlspace is not a plenum in Chapter 16 of the IRC. This change would essentially treat conditioned crawlspaces like conditioned basements, allowing fuel gas lines and plumbing waste cleanouts to be located therein. Conditioned crawlspaces are an increasingly popular strategy for bringing ductwork inside the conditioned space.

    Crawlspace is not a plenum (PDF 81 KB).

14. Add one county (Lake, Minnesota) that is currently missing from the county tables in Chapter 3 of the IECC and Chapter 11 in the IRC and correct the spelling of another county (Teton, Wyoming). Note that number 11 above also makes these corrections.

    County corrections (PDF 80 KB).

15. Make minor editorial corrections to footnote b (mass wall requirements) in Table 402.1.3 of the IECC.

    Mass wall footnote (PDF 83 KB).

Proposals Impacting Commercial Buildings

1. DOE has proposed modifications to Section 506 Total Building Performance. The modifications are intended to improve the usability of the Total Building Performance method and to make the Total Building Performance method more compatible with ASHRAE Standard 90.1's Energy Cost Budget (ECB) method. (Section 11 of ASHRAE Standard 90.1-2004 or 90.1-2007). DOE is also submitting a continuous maintenance proposal to ASHRAE for their Energy Cost Budget method that will bring Section 506 and the ECB method even closer together.

   Section 506 Total Building Performance of the IECC. (PDF 182 KB).

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