501 Main receives Efficiency Vermont’s 2025 Best of the Best Award for innovation in energy efficiency, affordability, and community impact.

Originally built in 1932 as Fairlee’s first post office, 501 Main has undergone a remarkable transformation.

501 Main, first conceptualized in 2020, reached occupancy in May 2023.

The mixed-use building is made up of eight apartments and a retail space located adjacent to Chapman’s General Store and replaces a long-vacant single-story commercial structure.

It is Fairlee’s largest apartment building and the first new multifamily development here in over 50 years.

With its warm, welcoming storefront and thoughtfully designed living spaces, 501 Main has quickly become a new hub for community life in the village

*The original building in the late 1940s.*

*Sunnyside Coffee has been a huge hit locally!*

Sustainability was a cornerstone of this project.

To reduce waste, as much of the original structure as possible was salvaged and repurposed.

The existing concrete foundation (equaling 50-plus cubic yards of concrete) was retained, and other materials found new homes: Fiberglass insulation and windows were donated to a young couple building their first house, millwork was provided to a local trade school for student projects, and structural steel was repurposed for the new construction.

*The original foundation was salvaged, reinforced, and built on top of.*

The building at 501 Main is also highly energy-efficient.

With the use of Aerobarrier and ZIP panels, it achieved an impressive blower door test score of 0.05 cfm50/sf (well below the Passivhaus standard).

Key features include triple-pane windows, blown-in cellulose in the attic, all-LED lighting, and a heat recovery ventilation (HRV) system that serves all nine units.

*Installing the water main. Exterior rigid insulation is showing prior to siding install.*

The building’s heat loss is minimal. Each apartment is heated and cooled with ultra-efficient 6,000 Btu heat pumps, the smallest available on the market.

Even with these higher, above code energy efficiency features, the project was built quite affordably. And the building is affordable for the tenants as well—after 18 months of operation, the project owners report that residents at 501 Main are spending an average of just $57 per month on electricity for lights, heat, hot water, and cooking.

Project technical details:

4,200 sq ft (8 apartments & one retail space)
Triple-pane windows with average U-factor of 0.18
Exterior 2x6 walls with dense-packed cellulose
3” of recycled polyisocyanurate rigid foam (~R40)
24” of blown-in cellulose insulation in the attic (~R70)
3” of closed-cell spray foam on basement walls (~R20)
0.27 ACH 50
All LED lighting
LifeBreath 267 HRV (ventilates all 9 units)

See our other projects

Stay building,

— Jonah

From Historic Post Office to Award-Winning Housing

Getting Started With An ADU