Boulder Energy Code Summary

Upcoming Changes to the Boulder Energy Code 

**Interested in attending a lunch and learn about the new codes?  Please email info@sustainablybuilt.com for the schedule**

The City of Boulder is adopting new residential and commercial energy codes, expected to be effective May 8th, 2017. The goal of the code update is to simplify confusing aspects of the code, as well as continue tightening the energy efficiency requirements of new buildings and major remodels/additions. In addition, the City has outlined the plan for future residential energy requirements, with a goal of net-zero for all new buildings and major remodels/additions by 2028.

The following is a summary of the changes:

Residential Code:

In the new code, residential buildings are defined as “single family homes, townhomes, duplexes, and R-3 and R-4 occupancy buildings (includes boarding and care facilities). Any mixed use or multifamily apartment or condo buildings, will be regulated under the commercial code.” This is a significant departure from the previous code, where multifamily units were required to have a HERS rating. In discussions with City staff, there was an indication that exceptions might be made, for instance if a multifamily complex were pursuing LEED, and required to have a HERS rating for LEED compliance. Additionally, this modification will not apply to any project which had submitted a complete site review application prior to the date of ordination adoption.

The Green Points checklist has been eliminated. Instead of a point system, some of the previous point options are now mandatory, including waste management, landscaping (xeriscaping), and efficient water fixtures. New requirements include pre-wiring for solar photovoltaic systems, installation of passive radon systems, and charging outlets for electric cars.

Per Figure 1, HERS score requirements for homes 1,500 sq ft and larger have been tightened, with new homes 5,000 sq ft and larger requiring a HERS 0. Figure 1 also outlines future HERS score requirements for the next rounds of code updates, resulting in all new homes being net-zero in 2028.

Figure 1: Map of HERS Score Requirements for Future Code Revisions

Per Figure 2, HERS score requirements for additions have been modified, with greater impacts to additions to larger homes. Homes less than 1,000 sq ft will still be allowed to follow compliance with previous IECC 2012 prescriptive requirements.

Figure 2: HERS rating requirements for additions

Per Figure 3, energy efficiency requirements for remodels will now be based on the ratio of project budget to assessed value of the existing home.

Figure 3: Energy Efficiency for Remodels

Commercial Code:

For new construction, the prescriptive path is greatly simplified for the commercial code. The Advanced Buildings New Construction Guide requirements from the current code are replaced by a modified version of the IECC 2012. Application of the prescriptive path is limited to projects whose valuation is less than $500,000. Projects over $500,000 will be required to show a 30% energy use reduction over the ASHRAE 90.1-2010 requirements via an energy model.

For additions/alterations of commercial building, Figure 4 outlines the new energy efficiency requirements:

Figure 4: Commercial Additions/Alterations

New commercial buildings will also be required to be pre-wired for solar photovoltaic systems, and will have electric charging station requirements. One additional requirement is an automatic HVAC system shutoff for operable windows.