
Green Castle Group. Filling the Gaps, Enriching Our Community.
At GCG, we strongly believe that infill development is the path to a sustainable community. At our core, we believe that utilizing our existing resources, revitalizing urban spaces, and reclaiming previously developed lands sustainably is the definition of smart growth, as it creates an even more walkable, connected community. Although often the most challenging projects technically, we are convinced that infill development solutions are the sustainable path toward the smart use of our existing resources.
Infill is where innovation meets our Burlington community.

Time Lapse of Work in Progress as of June 25
Introducing our newest Burlington housing innovation… The 266.
This landmark project, a joint venture between the Seizan Capital and Green Castle Group, involves restoration and preservation of the brick façade of Burlington’s circa 1932 YMCA. Development plans include:
- Preservation of the historic brick façade of Burlington’s prior YMCA
- Sustainably Designed to LEED Gold Standards
- 79 apartments
- Below-grade parking
- State of the art amenities and security
- On Site Management
Completed Award-Winning Projects

The Commons @ Hungerford
Completed in 2024, this planned unit development is another joint venture between the Seizan Capital and Green Castle Group teams. Steps from Burlington’s “Hill Institutions,” this complex encompasses more than 33,000 sf and 24 apartments on a very challenging site due to the presence of Burlington’s historic ravine, presenting grade changes of over 23’ and urban soils management issues. Owing to the degree of difficulty of the site and its state-of-the-art stormwater management solution, this project was recognized as the Outstanding Civil Engineering Project of 2025 by the American Society of Civil Engineers, Vermont Section.


Mansfield Hall
This 23,000 sf project located at 289-291 College Street, developed by Green Castle Group was designed to capitalize on its Hill Section location a four minute walk to UVM. This Property now is the home for Mansfield Hall and encompasses 13 apartments plus, counseling offices and common spoce amenities for its residents. Mansfield Hall is a living and learning community which provides on-site residential, academic, executive functioning, social, and independent living skill support to students.

323-325 College
Another urban infill Hill project, this apartment complex is located at 323-325 College Street, a block and a half from UVM Green. Developed by Green Castle Group, this Property when its last phase is complete will comprise over 39,000 square feet of living space and 58 bedrooms.

The Pearls
355 and 361 Pearl Street is an award winning planned unit development nestled a block from Burlington’s “Hill Institutions” boasting 20 spacious apartments. Winner of the Preservation Burlington Best Historic Renovation Award.

The Hamilton
This recently restored and reimagined historic building was made possible by utilization of owner developer knowledge of the complexities of the building codes to expand, reimagine and repurpose nearly 40% of underutilized space in this building with the property now boasting 14 apartment units.