Entrepreneurs, staff debate tiny homes, ADU classifications and SDCs in Milwaukie study session

Entrepreneurs who build tiny mobile units and Milwaukie planning staff met with council members at a study session to discuss how small, wheeled microhomes and accessory dwelling units (ADUs) fit local code and what barriers — classification, utility hookups and System Development Charges (SDCs) — would need to be addressed for broader use.

Adia De Torres, who said she and a partner build “tiny rooms on wheels, mobile rooms, or micro homes” intended for temporary housing, described use-cases such as placing units on partially developed lots while larger projects proceed, or placing units in backyards for homeowners to rent as supplemental income. “We built tiny rooms on wheels…a bedroom with a tiny microwave, fridge and a half bath,” she said.

Staff and council members discussed whether wheeled units are treated as vehicles (RV-style) or as ADUs when they are placed on private property. Ilya (planning staff) explained the distinction matters because ADUs can trigger different permit requirements and fees; the city cannot unilaterally waive third-party SDCs, staff said. A staff member clarified that Milwaukie can decide to cover or subsidize SDCs for a development but generally lacks authority to waive SDCs assessed by other agencies.

Speakers noted potential operational and safety questions for long-term use of units built for short-term occupancy: sewer and wastewater durability, winter freeze/thaw impacts on permeable paving, and how RV-style connections interact with local plumbing standards. Ilya and other staff said many tiny-home builders choose to build to residential standards — insulation, one-hour-rated walls and standard plumbing — to address these issues.

Council members and staff discussed options to encourage innovative small-housing forms: a targeted grant program to buy units for fixed-income homeowners, pilot allowances that treat wheeled microhomes as ADUs under limited conditions, and exploring SDC-incentive tiers that reduce fees for deed-restricted affordable units. Staff suggested organizing a follow-up work session to identify legal limits, safety standards, and potential subsidy mechanisms and noted planned public engagement on middle housing.

Why this matters: Tiny, modular and ADU-style housing can provide short-term shelter and a path to increased supply. The session underscored that converting these concepts into permanent policy requires clear local rules about classification, plumbing and stormwater connections, and a funding approach for any SDC relief.

Council members asked staff to return with options on code interpretation for wheeled units, potential pilot programs, and the legal and budget implications of SDC waivers or subsidies.