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Stretch Code for Residents

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1. What is the anticipated cost to the property owner of complying with the code?

In almost all cases, expected energy savings from complying with the stretch energy code will exceed the cost. New construction projects that are designed to meet the Home Energy Rating System (HERS) rating targets can do so cost effectively, as many builders have already demonstrated through the voluntary Energy Star Homes Program. In the case of building renovations, there are more design constraints, but lower standards to meet. Typical projects involve adding insulation and air sealing and will see relatively rapid paybacks. If major equipment upgrades are selected, then the payback could be longer. However, for renovations, equipment such as boilers and furnaces would not be required to be replaced, although the owner may have other reasons to do so.

The City of Cambridge hired the Vermont Energy Investment Corporation, a nonprofit energy organization that the Commonwealth of Massachusetts has used for energy expertise, to assess the impact on a triple decker building undergoing a major renovation. Using plans from an actual triple decker located on Magazine Street and assuming the project follows the performance path, the modeling indicates that it is relatively easy (e.g., add insulation and conduct air sealing) for the triple decker to achieve a HERS rating of 85.

The energy savings each year exceed the cost of financing the improvements. The savings estimate was conservative and did not include any utility energy efficiency incentives or tax incentives in the cost of meeting the code requirements. A copy of the modeling results is available from Cambridge’s Community Development Department.

2. Will implementing the stretch code save me money on utilities?

Yes. The stretch energy code is designed to tighten the building envelope and utilize efficient lighting, appliances, and equipment. As a result, the cost of heating, cooling, and electricity will decrease.

3. What low-cost interventions can I do to meet the stretch energy code?

For renovation projects, most projects will be able to meet the stretch energy code by adding insulation and performing air sealing, and measures such as applying caulk and adding storm windows. For new construction, the stretch energy code would require incremental improvements in measures and equipment installed, the cost of which will be quickly paid back in energy savings.

4. What kinds of projects trigger the stretch energy code?

New construction and renovations of residential buildings three stories or less would be subject to the residential portion of the stretch energy code. New construction projects would be required to use the Home Energy Rating System (HERS) and achieve an index level of 65 if the building is over 3,000 square feet in area or 70 if the building is smaller (see attached table).

Renovation projects would have 2 options:

• The performance approach requires achieving a HERS rating of 80 for homes over 2,000 square feet and 85 for those under 2,000 square feet.
• The prescriptive approach requires measures listed by the Energy Star for Homes Program, such as more efficient equipment, plus insulation at least equal to that required by the International Energy Conservation Code (IECC) 2009 code.

5. What is the Home Energy Rating System (HERS) rating?

HERS is the acronym for Home Energy Rating System. It is a scoring system established by the Residential Energy Services Network (RESNET), a national non-profit organization recognized as a national standard by such organizations as the Federal IRS, EPA, and the mortgage industry.

The scoring index is a scale from 0 up to around 200, with 100 representing the score for a 2006 code standard new home of the same size and type compared to the new home being evaluated. A score of 0 would represent a home that uses 0 net energy ( e.g., a 0 net energy home). Each 1 point decrease in the HERS index corresponds approximately to a 1% reduction in energy consumption. For example, a home that achieves a HERS rating of 85 would be 15% more energy efficient than the standard new code built home in 2006. Older, unimproved homes typically have ratings well over 100. The lower the score, the more efficient it is. The score is determined by energy modeling of the buildings structure and systems by a certified HERS rater.

6. What are the prescriptive measures that can satisfy the stretch energy code?

For residential projects, the prescriptive measures consist of the Energy Star Builders Option Package (BOP), which includes the Energy Star Thermal Bypass Checklist.

The BOP describes the insulation and air sealing to cut infiltration for an efficient building envelope, efficiency standards for cooling and heating equipment, allowable leakage rates for ductwork, and standards for windows, water heaters, lighting appliances, and thermostats.

Energy Star-rated equipment, appliances, windows, and lighting meet the standards. The thermal bypass checklist involves visual inspection of areas in the building where air leakage could take place to ensure that sealing is effective.

7. Can I limit a remodeling project to items of my own choosing?

Applicability of the stretch energy code to renovation projects is limited to the extent of the work. For example, if windows are being replaced, then the windows must meet the code’s standards and any exposed wall cavity must be filled with insulation to the required level. But, the remainder of the building would not be required to be upgraded. Similarly, if a ceiling or wall cavity is opened, then the required level of insulation must be installed, but the remainder of the building’s ceiling and wall cavities are not required t o be upgraded with insulation. If you are replacing your boiler, you would be required to install 1 that meets the stretch code standard, but you would not be required to upgrade the building insulation. Also, certain work is exempt, including re-roofing, installation of storm windows, and alterations involving less than 50% of light fixtures in a space.

8. If I’m doing a small remodeling project, like a kitchen or bathroom renovation, will I have to meet the stretch energy code?

If the work would normally trigger the base energy code, then it would trigger the stretch energy code. But, only those elements that are being changed would have to meet the code requirements.

9. Do I have to achieve a Home Energy Rating System (HERS) rating if my project is only a renovation of an existing building?

For a renovation, a HERS rating would be an option, not a requirement. The project could satisfy the stretch energy code through the performance track, which would involve a HERS rating, or the prescriptive track, which would require installing specified measures. Because the HERS rating is based on the performance of the whole building, in most cases it is expected that renovation projects will use the prescriptive track.

10. Would existing buildings or historic buildings have to be upgraded to comply with the stretch code appendix?

The stretch code appendix does not change the sections of the state base building code that apply to existing buildings and historic buildings. These sections have also remained unchanged in the base code between the 7th edition and the proposed 8th edition of the Massachusetts energy code. Specifically historic buildings listed in state or national registers, or designated as a historic property under local or state designation law or survey, or with an opinion or certification that the property is eligible to be listed, are exempt from both the base and the stretch appendix to the energy code.

11. As a residential property owner, how would I comply with the stretch energy code?

If the project involves new construction, then it must follow the performance track, which is based on a Home Energy Rating System (HERS) rating. If the project involves a renovation, it can comply by following either the performance or prescriptive track.

12. What categories do multifamily residential buildings fall into?

Residential multifamily buildings that are above 100,000 square feet and at least 4 stories tall have to follow the same performance path (20% better than the American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) standard 90.12007) as other commercial buildings larger than 100,000 square feet. Residential buildings between 5,000 and 100,000 square feet and at least 4 stories tall would be classified with commercial buildings between 5,000 and 100,000 square feet. Multifamily buildings with 1 to 3 stories of any size fall under the residential stretch code standards. In the rare case of a multifamily building of 3 stories or less that is larger than 100,000 square feet, the developer may elect to be treated either as a residential or as a commercial building.

13. What training do Home Energy Rating System (HERS) raters undergo?

HERS raters are typically experienced building design professionals who additionally undergo an intensive one to two week training course and must rate 5 homes under the supervision of an existing certified HERS rater in order to be certified by Residential Energy Services Network (RESNET).

They must also be part of a HERS rating agency or organization that provides quality assurance, liability insurance, and ensures that raters meet ongoing continuing education requirements.

14. How do I find a Home Energy Rating System (HERS) rater?

NSTAR can assist contractors and owners in finding a HERS rater. They are also listed at online.

15. How could my contractor know how to meet the stretch energy code?

The state will hold trainings for contractors and municipal inspectors. We expect trade groups will also hold their own trainings. The town’s Building Department would provide information to all permit seekers about the need to comply with the stretch energy code.

16. What kinds of technical and financial help are available to property owners and contractors?

In addition to the trainings that will be offered by the state, owners, and contractors will have access to the energy efficiency services, including financial incentives and loan programs, accessible through NSTAR.

17. How would the stretch energy code be enforced?

The Town of Brookline Building Department will be responsible for enforcement of the stretch energy code in the same manner that it currently enforces the existing building and energy codes.