Accessory dwelling unit new hampshire — St. Louis, MO

Last updated: September 24, 2026

What affects the price

Building an ADU is a custom project, so costs vary based on your specific choices. Site conditions are the biggest factor; if your land requires significant grading, utility extensions, or foundation work, those expenses add up quickly. Choosing high-end finishes, custom cabinetry, or complex roof lines will also push the budget higher compared to a standard design. Prefabricated units often offer predictable costs, while custom site-built structures allow for more flexibility but can be harder to estimate upfront. Exact pricing confirmed free on the call.

About this service

Building an ADU in New Hampshire involves meeting specific state-level guidelines while navigating local zoning ordinances. Requirements like separate utility metering, parking mandates, and size limits can vary from town to town. If you own a residential lot in the Granite State, we can help you determine if your property qualifies and what design options are permissible under current law. Exact pricing confirmed free on the call.

Frequently asked in St. Louis

Also serving nearby: O Fallon · Springfield · Columbia · Champaign · Peoria

All cities in Missouri →

More on this: HUD ADU resources — ADU policy and financing research.

Service area details

Serving all of St. Louis — population 281,754; about 4,565 residents per square mile across 61.7 sq mi.

Neighborhoods served in St. Louis: Soulard, Central West End, Tower Grove South, The Hill, Benton Park — and every surrounding area.