Code officials, builders, efficiency advocates, and other interested parties are in Kansas City this week and next for the International Code Council’s annual conference and public comment hearings. We’ll be putting in some long days with the goal of developing final recommendations for the 2018 International Energy Conservation Code (IECC, the model energy code recognized by the Department of Energy (DOE) and cited in federal law, which is updated every three years through a stakeholder process. It's then up to local jurisdictions to adopt and enforce the codes).
There are many, many proposals on the table for consideration, for both residential and commercial buildings. Some of these proposals improve the energy efficiency of the code, but many of them make the code less stringent. As I talked about in a blog post written after the Technical Advisory Committee hearings in the spring, the building energy code is under attack at precisely the time when it is crucial to ensure that code is stronger than ever. NRDC will spend our time at the hearings pushing for more efficiency in buildings – and pushing back on proposals that weaken the code – which will mean better, more efficient buildings that use less energy, cost less for homeowners and business owners to operate, and emit less carbon pollution. And when we're not in the hearing room, you'd better believe we'll be sampling some of that famous Kansas City barbecue.
Why Does This Matter?
Americans spend more than $200 billion each year on their energy bills. A recent report from the Department of Energy found that a modest 4 percent to 5 percent increase in the stringency of the building energy code will cumulatively save consumers $126 billion on their energy bills from 2010 to 2040. Likewise, making the building energy code less efficient will cost consumers money in the form of higher energy bills. Building codes have been incredibly effective at reducing the energy use of a new home over time, ensuring that home buyers benefit from advances in home-building technology. The downward trend in the energy consumption of a new home, driven by stronger energy codes, is a crucial part of reducing greenhouse gas pollution emissions and keeping utility bills affordable.
For the purposes of this blog post, we’re focusing on the residential proposals. We’ll be back after the hearings conclude with a roundup of all of our final voting recommendations, for both the residential and commercial codes.
A home can comply with the energy code by following one of three paths: the prescriptive path, the performance path, and the Energy Rating Index path. The prescriptive path has specific requirements for individual energy efficiency measures (ie, insulation level, window efficiency, building materials, etc) that must be met. The performance path requires that the proposed design of a home is shown to have an annual energy cost that is less than or equal to the cost of a standard reference design. The Energy Rating Index (ERI) path, which was added to the code in 2015, rates scores on an index of zero to 100. Homes that comply with the minimum requirements of the 2006 IECC score a 100, homes use no net purchased energy score a zero; compliance with the 2015 code requires homes to have a score between 51 and 55 depending on climate zone.
Here’s the scoop on some of the residential proposals we’ll be closely following:
Proposals that Improve Energy Efficiency
RE31 or RE19 – Improved Windows
- Either of these proposals will require more efficient windows in all paths of the code.
- The efficiency levels specified are already widely available.
RE113-16 – Prescriptive Water Heater Efficiency
- For homes in climate zones 1-5 (see map below) complying with the code using the prescriptive path, this proposal requires the use of one of six types of water heaters.
- As the residential thermal envelope (meaning all the parts of a home that separate the conditioned space from the outdoors or unconditioned space: insulation, windows, exterior walls, roof, etc) has gotten better in recent code cycles, water heating has become a proportionally higher end-use.
- This proposal helps to ensure that homeowners aren’t wasting energy on heating water, and does so in a way where the options are cost-effective for the homeowner.
RE114-16 – Reducing Bathroom Faucet Flow
- This proposal limits the flow rate of a faucet found in a bathroom to 1.5 gallons per minute, which is equivalent to the flow rate met by faucets that comply with the EPA Water Sense program.
- Many fixtures on the market already comply with this flow rate, which has been proven to save energy and water
- There is a public comment which proposes to create a new section of the code focusing specifically on water conservation and efficiency, including this proposal. NRDC supports this idea.
RE135-16 – Stronger Envelope Requirements for the Performance Path
- This proposal applies the same minimum thermal envelope requirements to the performance path as is required in the Energy Rating Index path
- The Energy Rating Index path currently requires a tighter, more efficient building envelope than the performance path, so applying the same requirement to this path would make homes more efficient.
RE166-16 – Reference to ANSI/ICC/Resnet 301 Standard in the ERI Path
- This proposal adds certainty to the ERI path of the code by clarifying that the calculation of the ERI score shall be done in accordance with the ANSI/ICC/Resnet 301 standard. This is already the industry standard, so there is very little functional change that will occur as the result of this proposals – but it ensures that all customers are receiving a high-quality product if their home complies with the ERI path.
- However, the ANSI/ICC/Resnet 301 standard allows for an unlimited amount of on-site energy generation. Adoption of RE166-16 should be paired done in conjunction with one of the proposals that limits credit for on-site energy generation.
One of the proposals that limits credit for on-site energy generation in the ERI path of the code
- There are a number of proposals which seek to limit the amount of on-site energy generation that is permissible in the ERI path. This issue is particularly relevant when talking about renewable energy generation (such as solar photovoltaic), but can apply to any type of energy generation, renewable or not.
- While NRDC wholeheartedly supports renewable energy, the building code should prioritize energy efficiency because it is still the cheapest way for a consumer to use less energy. The fear is that a builder could construct a very inefficient home, then “make up the difference” with on-site generation – that could lead to higher costs for the customer.
- The relevant proposals use a variety of mechanisms to limit the amount of credit that on-site energy generation could receive.
RE179-16 – Flex Points
- This proposal improves the efficiency of all compliance paths by 5%. It’s the only proposal that includes this kind of across-the-board improvement, and as I mentioned in my last blog post, a 5% improvement in the code is quite reasonable and necessary.
- Builders choose from a menu of options that will improve the energy efficiency of the home, anything from reducing air leakage to improving the heating or cooling system efficiency. A home must achieve 5 flex points, but can do so through a variety of different means.
- This proposal keeps the code moving toward greater efficiency, but does so in a way that provides maximum flexibility and allows for new and innovative technology to get credit.
Proposals that Weaken the Code
RE87-16 – Increased Air Leakage
- This proposal reduces the efficiency of a home by allowing for more air leakage in climate zones 3-8.
- A leakier home means that more heated or cooled air escapes to outside of the building envelope. This is a clear rollback of the code.
RE130 – Including Lighting in the Scope of the Performance Path
- Lighting is not currently part of the performance path of the code, meaning that a home must already meet minimum mandatory lighting efficiency levels.
- There is no prescriptive path for lighting in part because the level of illumination varies so much from house to house. Homes are unlike commercial buildings, where one can estimate energy use based on providing a standard recommended level of illumination. This proposal would not specify how lighting energy use is calculated in a way that on one hand prevents excessive light levels and on the other does not reward such dim lighting that the user would later install lots of portable lighting. That’s a big loophole and would be bad for homeowners.
RE134-16 – Equipment Trade-Offs in the Performance Path
- Allows a builder to trade off the efficiency of the thermal envelope (windows, walls, etc) for heating, cooling, and water heating equipment
- Builders would be able to take credit for any efficiency gains between the federal minimum standard HVAC equipment and the type of equipment they install, and instead install less insulation or less-efficient windows. The issue is that, in many places, more than 90% of equipment installed is already more efficient than the minimum standard.
- This creates a huge free-ridership loophole and will result in a less-efficient home.
- There is a public comment (PC2) that would eliminate the equipment tradeoff but add flexibility in the thermal envelope backstop, which NRDC supports.
The code has the potential to be strengthened or weakened significantly based on the outcome of the IECC hearings. Our future depends on using all of our natural resources as efficiently as possible, and NRDC will work to make that future a reality.