16-642 C.M.R. ch. 6, § 6 - REVISIONS TO THE RESIDENTIAL PROVISIONS OF THE 2021 IECC

The following additions, insertions, deletions, and other changes are hereby made to the 2021 International Energy Conservation Code, Residential Provisions:

1. Section R101.1

Delete [NAME OF JURISDICTION]; and

Insert "State of Maine" in its place.

2. Section R102.1.1

Delete from language "The code official or other authority having jurisdiction shall be permitted to deem a national, state or local energy-efficiency program to exceed the energy efficiency required by this code. Buildings approved in writing by such an energy-efficiency program shall be considered to be in compliance with this code"; and

Insert "Buildings certified in compliance with Passive House, Phius, or the US Department of Energy's Zero Energy Ready Home programs shall be considered in compliance with the Energy Code" in its place.

3. Section R102.1.2

Insert new section "R102.1.2 Optional Appendices.

Appendices RB, and RC of the 2021 IECC are intended to provide flexibility to permit the use of more than one approach or technique to achieve compliance with the code."

4. Section R.102.1.2.1

Insert new section "R102.1.2.1 Appendix RB.

Where new construction satisfies the provisions of Appendix RB of the 2021 IECC and Section R401.2 it shall be considered in compliance with the Energy Code."

5. Section R.102.1.2.2

Insert new section "R102.1.2.2 Appendix RC.

Where new construction satisfies the provisions of Appendix RC of the 2021 IECC and the requirements identified in Table R405.2 it shall be considered in compliance with the Energy Code."

6. Section R104

Delete Section R104 "Fees" in its entirety, without substitution. Fees are a local permitting issue.

7. Section R110

Delete Section R110 "Means of Appeals" in its entirety, without substitution. Appeals are handled at a local level.

8. Table R402.1.3

Delete values from column "Wood Frame Wall R-Value" in "Climate Zone" rows "6" and "7 and 8"; and

Insert "30 or 20 + 10ci or 13 + 15ci or 0 + 20ci" in its place.

As shown below:

CLIMATE ZONE	WOOD FRAME WALL R-VALUEg
6	30 or 20 +10ci or 13 + 15ci or 0 + 20ci
7 and 8	30 or 20 +10ci or 13 + 15ci or 0 + 20ci

Informational Note: Remainder of table remains unchanged.

9. Section R402.2.13

Insert a new section "R402.2.13 Above grade walls. Above grade walls shall comply with this section."

10. Section R402.2.13.1

Insert a new section "R402.2.13.1 IRC Compliance.

Insulation for above grade walls must also show compliance with IRC Section R702.7."

11. Section R402.2.13.2

Insert a new section "R402.2.13.2 Exterior insulation.

Where insulation for above grade walls uses less than R-10ci for exterior insulation, a dew point calculation showing that the temperature of the condensing surface is greater than 41 degrees F at 35% humidity shall be completed by a registered design professional or approved agency and provided to the code official for review.

Exceptions:

1. Where the wall assembly uses cavity only insulation.

2. Where the wall assembly has a permeability of greater than 5 perms."

12. Section R402.4.1.2

Delete (from the second sentence) "5.0"; and

Insert "3.0" in its place.

Delete (from the second sentence) "0.28"; and

Insert "0.20" in its place.

13. Section R402.4.1.3

Delete Section R402.4.1.3 in its entirety.

14. Section R402.4.7

Insert a new section "R402.4.7 Bulkhead enclosures.

Where a bulkhead enclosure is installed for basement access, a wall and vertical door must be installed at the base of the stairs or where the bulkhead enclosure meets the basement wall and must be air sealed in accordance with Table R402.4.1.1."

15. Table R405.2

Insert new row in table (after "R402.2.10.1| Crawl space wall insulation installation") with the text "R402.2.13" in the first column and "Above grade walls" in the second column.

As shown below:

Building Thermal Envelope
R402.1.1	Vapor retarder
R402.2.3	Eave baffle
R402.2.4.1	Access hatches and doors
R402.2.10.1	Crawl space wall insulation installation
R402.2.13	Above grade walls

Informational Note: Remainder of table remains unchanged.

APPENDIX NA. MUBEC STRETCH CODE

The 2021 Stretch Code is created to lower energy consumption in both commercial and residential projects compared to the 2021 IECC.

Commercial Projects: The Total Building UA for the project, calculated as outlined in C402.1.5, shall exceed the UA requirements by at least 15% over a code compliant project. This means that the Envelope PASSES design by 15% better (or more) than code per the COMCheck compliance calculation.

Residential Projects: The Total Building UA for the project, calculated as outlined in R402.1.5, shall exceed the UA requirements by at least 15% over a code compliant project. This means that the Envelope PASSES design by 15% better (or more) than code per the RESCheck compliance calculation. For residential projects that do not include fossil fuels for any use (heating, cooling, hot water, backup heat, cooking, etc.) the Total Building UA shall exceed the UA requirements by at least 10% over a code compliant project. This electrification incentive allows the use of fossil fuels for backup power generation.

Notes

16-642 C.M.R. ch. 6, § 6