ADU — Detached 1-bedroom Cost in Chicago, 2026

Why detached 1-bedroom × Chicago produces this band

A detached 1-bedroom scope for a adu in Chicago combines two price levers: scope and metro labor rates. A detached 1-bedroom ADU is the category anchor: 500-750 SF standalone unit with a full kitchen, full bath, and bedroom. Separate foundation, roof, MEP, and entrance. Against the national median remodel labor rate, Chicago runs 15% above the national median — so the detached 1-bedroom band comes in at the mid-range, then scales 15% above the national median on top of that. Permit timelines for residential work in Chicago typically run 6-14 weeks, which is the window you plan your design and decision sequence against. This page gives you the actual 2026 Chicago bands for this exact combination, plus the three cost drivers Baily asks about first when scoping the project live.

What drives cost for a detached 1-bedroom scope

• ·New foundation (slab-on-grade or stem-wall)
• ·New roof system and weather envelope
• ·Full MEP rough-in from the street (water, sewer, gas, electric)
• ·Site prep, grading, drainage

What makes Chicago different

• Labor — Union trades (carpentry, electrical, plumbing) are the majority of licensed remodel labor — premium over national median.
• Labor — Winter shuts down most exterior trades Dec-Feb, compressing schedules into a 9-month season.
• Labor — Chicago Prevailing Wage Ordinance drives labor costs on any publicly-touching work.
• Material — Midwest steel and framing lumber are priced competitively vs coasts.
• Material — Masonry restoration (common in pre-war Chicago brick) uses specialty materials with long lead times.

Chicago rules that affect this scope

• Chicago DOB self-certification is available for registered architects — compresses permit timelines.
• Landmark districts (e.g. Lincoln Park, Old Town Triangle) require Commission on Chicago Landmarks review in addition to DOB permit.
• Chicago Energy Conservation Code (IECC 2021) applies to all work changing envelope or HVAC.
• Two-flat and greystone conversions frequently trigger zoning variance — timeline extension of 8-14 weeks.

Scope your adu with Baily.

Baily asks the eight questions that determine where your project lands inside the $207K-$437K band for Chicago and hands the scoped brief to one licensed builder.

Related pages

Questions LA homeowners actually ask

• What is the 2026 cost range for a detached 1-bedroom scope adu in Chicago?

  $207,000-$437,000, with the median landing near $322,000. The range reflects finish tier and layout complexity within the detached 1-bedroom scope; the Chicago labor multiplier of 1.15× vs national median is baked in.

• How long does a detached 1-bedroom scope adu take in Chicago?

  26-40 weeks of on-site construction for the detached 1-bedroom scope, plus 6-14 weeks of permit review in Chicago if the scope requires a permit. Cosmetic-only refreshes often skip permits; anything touching plumbing, electrical, or structural does not.

• What is the single biggest budget-overrun risk for this scope?

  Sewer connection — if the existing lateral runs under the new foundation line, a new lateral cut plus utility easement and right-of-way bond can add $12-22K.