02-385-110 Me. Code R. § 2-11

Current through 2024-51, December 18, 2024

Section 385-110-2-11 - Energy Standard for State-Certified Modular Homes

1. Purpose and Scope

The purpose of this standard is to provide a reasonable energy code, based on nationally recognized codes, that will apply to all State-certified modular homes that are installed in Maine. This standard sets forth design and construction requirements relating to energy efficiency in State-certified modular homes.

2. Compliance; Limited Waiver of Compliance with Energy Specifications Table

State-certified modular homes must comply with the provisions of this Section. The executive director may waive compliance with the Energy Specifications Table contained in subsection 6(A) below in the limited circumstances described in subsection 6(N) below.

3. Materials and Equipment

Materials and equipment must be identified in a manner that will allow a determination of their compliance with the provisions of this chapter. Materials and equipment used to conform to the applicable provisions of this chapter must be installed in accordance with the manufacturer's installation instructions. (2009 IRC, N1101.7)

4. Identification

Materials, systems and equipment must allow a determination of compliance with these codes and standards adopted.

5. Building Thermal Envelope Insulation

The home manufacturer shall provide in the plans approved by the board or by an approved inspection agency a listing of the minimum R-value and/or U-value (as appropriate) of insulation installed or to be installed by a licensee of the board. Any insulation installed in the field by a licensee of the board must be installed in accordance with the installation requirements of the insulation manufacturer. The home manufacturer shall state areas within the envelope of the home manufactured by it that need to be field insulated to meet code and what R-value and/or U-value (as appropriate, if using field windows and doors) must be obtained.

6. Energy and Efficiency Standards

A. Energy Specifications Table

The values listed in the Energy Specifications Table below are minimum standards for State-certified modular homes (one and two family homes and townhouses).

Energy Specifications Table

Minimum InsulationR-Value				Maximum FenestrationforExterior DoorsU-Factor		Maximum Fenestration for Windows¹U-Factor	Maximum Fenestration for SkylightsU-Factor
Ceilings	Roof/Ceilings	Walls	Floors	Entrance	Specialty
R-38	R-38	R-19	R-19	.35	.45	.35	.6

¹The term "windows" includes sidelights, octagonal, elliptical, transom, etc.

B. Perimeter Space

For 2-story homes, the perimeter of the space between the top of the second floor rim joists and the finished ceiling below must be insulated to R-19.

C. Unfinished Second Floors

Homes delivered with an unfinished second floor must be insulated as described below:

(1)Stair enclosures - The ceilings of the stair enclosures must be insulated to R-30. The walls of stair enclosures must be insulated to R-11.

(2)Doors - To prevent heat loss into the unfinished space, doors within stair enclosures must be either an exterior door or insulated by any means, including temporary means, to R-19.

(3)Ceilings - The floor/ceiling assembly between the first and second stories must be insulated to R-30, except that the ceiling area beginning at the outside walls and extending to the knee walls must be insulated to R-38.

D. Basement Stair Enclosures

Basement stair enclosures of homes with an unconditioned basement must be insulated as described below:

(1) The ceilings of the basement stair enclosures must be insulated to R-19; and

(2) The walls of the basement stair enclosures must be insulated to R-11.

[NOTE: See the definition of "conditioned space" in 2009 IRC, R202.]

E. R-value Computation

Insulation materials used in layers, such as framing cavity insulation and insulating sheathing, must be summed to compute the component R-value. The (insulation) manufacturer's settled R-value must be used for blown-in insulation. Computed R-values may not include an R-value for other building materials or airfilms (2009 IRC N1102.1.1) such as framing, drywall, structural sheathing or exterior siding materials. Insulation separated from the conditioned space by a vented space may not be counted towards the required R-value.

[NOTE: See the definition of "conditioned space" in 2009 IRC, R202.]

F. Exterior Walls

Insulation in exterior walls must be placed so that the entire cavity is insulated, including the space between the back of electrical boxes and the exterior sheathing.

G. Air Leakage

The building thermal envelope must be durably sealed to limit infiltration in accordance with 2009 IRC, N1102.4.1.

H. Air Sealing and Insulation Demonstration of Compliance

The durable sealing of the building thermal envelope required by paragraph G above is subject to verification if deemed necessary by the executive director. In such event, durable sealing must be demonstrated by the visual inspection option contained in 2009 IRC, N1102.4.2.2. A decision of the executive director to require verification is final and may not be appealed to the board.

I. Draft Stop

Draft stop materials must be placed along the entire perimeter of the interconnecting modules.

J. U-factor

U-factors of fenestration products must be determined in accordance with the National Fenestration Rating Council, Inc. (NFRC), NFRC 100-2010.

K. Waiver of Compliance with the Energy Specifications Table

(1) A manufacturer may obtain a waiver of compliance with the Energy Specifications Table contained in Subpart B, Section I-A(F)(1) by demonstrating to the executive director of the board that the design or construction of a dwelling makes it infeasible, as set forth below, to apply one or more of the values contained in the Energy Specifications Table. The waiver request must be made prior to acceptance of the plans by the manufacturer's board approved third-party inspection agency.

(2) In determining feasibility of compliance with the Energy Specifications Table, the executive director shall consider as alternatives to a waiver the manufacturer's ability to achieve compliance through alternative construction techniques, use of different materials, or design change. The executive director may also consider other relevant factors, including cost of compliance with the Energy Specifications Table, although cost of compliance alone is not a ground for obtaining a waiver. It is the intent of the board that waivers be sparingly granted.

(3) To receive a waiver, a manufacturer must further demonstrate that the U-value of the design for which the waiver was granted meets or exceeds the REScheck target value as calculated (using Climate Zone 6 for the entire State of Maine, including Aroostook County) under the trade-off approach for the 2009 edition of the International Code Council International Energy Conservation Code (IECC). This demonstration must be made in the form of a REScheck compliance certificate signed by the board-licensed manufacturer and the inspection agency, with the supporting inspection checklist attached.

(4) The executive director's denial of a waiver must be made in writing, must state the basis for the denial, and must inform the manufacturer of the time and manner in which an appeal to the board may be taken pursuant to Subchapter 6.

[NOTE: REScheck is available at no cost at from the U.S. Department of Energy at the following URL:

www.energycodes.gov/rescheck/]

L. Furnaces and Boilers

Gas-fired or oil-fired furnaces and hot-water boilers rated at less than 300,000 BTU/h must have a minimum AFUE rating of 78% in accordance with the United States Department of Energy (DOE) 10 CFR Part 430, Subpart B, Appendix N, entitled "Uniform Test Method for Measuring the Energy Consumption of Furnaces and Boilers" (January 20, 2010).

02-385 C.M.R. ch. 110, § 2-11