Overview

Willoughby Corner is a master-planned greenfield project born of an intergovernmental agreement between Boulder County Housing Authority (BCHA), Boulder County, and the City of Lafayette. The development is all-electric and, when fully built-out, will offer 400 below-market-rate rental and permanently affordable for-sale homes across several apartment buildings, duplexes, and townhomes. The development also includes nearly $14 million of public improvement infrastructure. Phase 1 of the development was completed in December 2024 and includes one 63-unit apartment building for 55-and-over residents, four buildings with 129 units serving families, and one community center.

Electrification Strategies and Features

As Boulder County aspires to be a leader in sustainability, BCHA’s decision to pursue all-electric development at Willoughby Corner was a natural one. When it came to system selection, BCHA relied on the expertise of their design team to help analyze the trade-off between increased up-front costs for higher efficiency systems with lower operating costs versus lower up-front costs for less efficient systems with higher operating costs. Ultimately, BCHA decided to invest up-front to make Willoughby Corner a highly energy-efficient community, a decision driven in part by BCHA’s policy of covering the costs of utilities for residents in their developments and their focus on keeping operating costs low.

Financing and Cost

The total development cost (TDC) of Phase 1 of Willoughby Corner was $106.4 million. The per unit per annum (PUPA) cost is $7,500 (2024). This is lower than the Boulder County average of $7,677 (CHFA Per Unit Per Annum (PUPA) Reporting).

BCHA noted that because Willoughby Corner is a master-planned community, they achieved an economy of scale while purchasing materials for the development. The project team felt that the efficiency achieved through the simultaneous development of two distinct types of housing saved them time and money compared to a scaled-down development strategy, despite the sometimes-increased administrative burden.

BCHA secured the 45L tax credit available, in part, due to the Zero Energy Ready Homes (ZERH) certification for this development, a tax credit for eligible new or substantially reconstructed homes that meet applicable ENERGY STAR home program or DOE ZERH program requirements. Because Willoughby Corner is ZERH certified, BCHA was eligible for the higher credit associated with 45L and used this to help offset the up-front cost of the geothermal system.

This project was developed during a time of market volatility (COVID-19 pandemic, supply chain issues, etc.), so BCHA opted for rate locks on construction and permanent loans, to minimize uncertainty and lock in the terms of those funding sources.

Successes

BCHA attributes much of the success of Willoughby Corner Phase 1 to deciding early in the planning process to pursue all-electric development. Notably, they included this decision in all Request for Proposals (RFPs) and were able to find experienced professional consultants to help make the project a success.

Willoughby Corner Phase 1 employs a highly efficient and sophisticated heating, ventilation, and air conditioning (HVAC) system. The use of ground source heat pump (GSHP) technology proves that multifamily affordable housing is not only able to keep pace with market-rate developments but can be a leader in building electrification. This is further evidenced by BCHA’s choice to pursue a 2021 IECC compliant building envelope—a major investment in energy efficiency at Willoughby Corner.

Further, even with the inclusion of paid utilities for all residents, Willoughby Corner has a PUPA cost that is slightly lower than the Boulder County average of $7,677, as reported by CHFA (2024). This demonstrates that all-electric developments are not always more costly to operate than their mixed-fuel counterparts.

Lessons Learned

Learning from their challenges is a major piece of BCHA’s development strategy, and they have identified several lessons from Phase 1 of Willoughby Corner’s development.

A project of this size—five residential buildings and one community building—requires a large workforce to match. While this has not been a major challenge in this development, BCHA’s partners have let them know that the rapid growth in demand for installers trained for all-electric development has pushed more individuals to enter the field recently and produced a younger, less experienced workforce. Naturally, newer installers will gain experience with time and practice, especially as the demand for this skilled labor continues to grow. In the near future, BCHA will consider these factors when planning timelines and phases for their larger projects.

Initially, BCHA had intended to use a central energy recovery ventilation (ERV) system at Willoughby Corner. ERV is a best-in-class system that pre-conditions a building’s fresh air supply using a heat exchanger connected to exhaust air, reducing heating loads and contributing to lower operating costs. However, BCHA has become aware of the increasing use of methamphetamine in Boulder County communities and is concerned about the potential risk this can pose to indoor air quality. Rather than opting for a central system for ventilation which would potentially recirculate contaminants throughout the property, they decided to use a supply-only ventilation system which will not reduce operating costs as much as an ERV but will be safer for residents if contaminants were to ever be present.