The significant changes being proposed for the energy code are described in detail in the April 16, 2019 City Council Memo. The presentation can be found at this video link. The most significant changes being proposed are:
More stringent Energy Rating Index (ERI) requirements
An ERI score is the same as a Home Energy Rating System (HERS) score. This is a numerical score where 100 equates to the efficiency levels prescribed in the 2006 International Energy Conservation Code and 0 is equivalent to a net-zero-energy home. In the 2020 code, new construction and major alteration projects must demonstrate compliance with Boulder’s energy code by using the prescribed ERI compliance path. In the 2020 code ERI scores are getting more stringent compared to the 2017 code.
With the cost of renewables decreasing, some projects simply deploy large solar arrays to achieve building performance requirements instead of investing in basic building efficiency. With this code update, an envelope backstop is being introduced that will ensure all elements of the building enclosure: windows, walls, floor slabs, roof assemblies, and doors are energy efficient. Each project will need to comply with prescriptive building envelope requirements in the energy code.
Similar to requirements that already exist for Boulder County projects, all residential pools, spas, outdoor radiant heating, and snow melt systems will be required to offset 100% of the system’s annual energy use by on-site renewable energy generation.
Construction & Demolition Waste Requirements
For over a decade, Boulder’s codes have included construction and demolition waste requirements for residential projects. With this code update, these requirements are being expanded to commercial projects. Additionally, improvements are being made to the code provisions and enforcement practices, including the addition of a requirement for a refundable deposit at the time of permit application.
Code Provisions for Alterations
Currently, the 2017 code requires additional energy efficiency improvements be made when renovating homes. The requirements are currently based on the construction value of the project. The 2020 code continues to require energy efficiency improvements for home renovations; however, the requirements are now triggered by the level of alteration as defined in the 2018 Existing Building Code.
Energy Use Index (EUI) Performance Path
The 2020 code introduces an EUI target compliance path that allows Boulder to transition towards outcome-based compliance, which staff and our consultants believe will be necessary to meet the City’s building energy efficiency goals.
To meet long-term NZE performance goals, it is necessary to encourage the deployment of renewable energy at the project level. The 2017 code mandates solar-ready requirements. In the 2020 code, at least 5% of commercial building energy use be supplied by on-site renewables for new construction.
Pilot for Outcome-Verified Code Path
The 2020 code provides an outcome-verified code compliance path. Ultimately, the 2031 goal of Boulder’s energy code is to set standards that will result in buildings that are NZE, not just in theory and as designed, but verified through metered data once the building is constructed, commissioned, and occupied. The outcome path included in the 2020 code would achieve this goal for projects that opt into this path.
Electric Vehicle (EV) Charging Requirements
In 2017, provisions were added to the code requiring commercial and residential projects provide EV charging infrastructure. Because technology has evolved and the demand for EV charging is better understood, the 2020 code clarifies and adjusts these requirements for commercial projects.