Second Suite: ADU Design and Tiny Homes in the Twin Cities
Second Suite is a design-focused service offering from Christopher Strom Architects (CSA), specializing in Accessory Dwelling Units (ADUs) and Tiny Homes across the Twin Cities metro area. Their work spans backyard cottages, in-law suites, above-garage apartments, basement conversions, and attached additions — each tailored to the specific property, goals, and local zoning requirements of the homeowner.
The team brings architectural expertise and deep familiarity with Minneapolis and St. Paul residential zoning codes to every project. Chris Strom, the founder and principal architect of CSA, has over 20 years of architectural experience and has served as an advisor to city zoning staff on residential code changes, including the adoption of the Accessory Dwelling Unit Ordinance in Minneapolis. He has been widely referred to as the Twin Cities' ADU Guru.
Second Suite handles the full process — from initial feasibility assessment through design, permitting, and construction coordination — making them a comprehensive resource for homeowners considering an ADU on their property.
ADU Types and Design Approach
Second Suite works on a range of accessory dwelling unit types, including:
- Detached backyard cottages
- Above-garage apartments
- Basement or attic conversions
- Attached in-law suite additions
Each project is custom-designed by Christopher Strom Architects. Homeowners can choose to have their ADU blend with the character of the existing home, or opt for a more contemporary design that contrasts with the primary structure. Past completed projects include designs named Sunflower, Compact Living, Alley Cat, and GreenHouse, which offer a sense of the range and style of their work.
ADUs serve a variety of practical purposes — multigenerational living, housing for adult children or aging parents, home offices, rental income, or simply additional flexible space. A well-designed ADU can also increase a property's resale value and long-term versatility.
In terms of cost, most ADU projects in Minneapolis and St. Paul range from $400,000 to $600,000, depending on size, type, and design complexity. The full process — from design through permitting and construction — typically takes around 12 months.
Twin Cities ADU Regulations and Eligibility
Both Minneapolis and St. Paul permit ADUs on most residential lots, subject to zoning, size, and setback requirements. Minneapolis was the first city in Minnesota to legalize ADUs in 2014, with Chris Strom playing a direct role in shaping that ordinance. St. Paul followed in 2018, and St. Louis Park in 2020. Chris also assisted the City of Edina in developing their ADU ordinance, which took effect in 2024.
A growing number of Minnesota cities now permit ADUs, including Bloomington, Burnsville, Columbia Heights, Crystal, Duluth, Eagan, Fridley, Golden Valley, Richfield, Rochester, Wayzata, and others. Each municipality has its own set of regulations, and Second Suite is experienced in navigating these local requirements.
For homeowners unsure whether their property qualifies, Second Suite offers an ADU feasibility study. This review covers zoning classification, lot size, setbacks, and utility access, and results in recommendations based on local code and the homeowner's specific goals.
All ADUs in the Twin Cities require building permits and zoning approvals. Second Suite manages this process from initial feasibility through final approval. They are also open to working with a homeowner's preferred builder, or can suggest builders who align with the project's priorities.
Regarding rental use: in both Minneapolis and St. Paul, ADUs may be rented as long-term housing. Short-term rental arrangements, such as Airbnb, are subject to restrictions depending on the specific jurisdiction.
