Detroit ADU permit requirements
Last reviewed: June 22, 2026
Quick answer
Permitting an accessory dwelling unit (ADU) in Detroit, Michigan means pulling a building permit from the local authority that issues it. ArchPermit tracks 16 source-cited requirements (13 required, the rest conditional) for this jurisdiction. Submittals go through eLAPS / Accela Citizen Access + ProjectDox. These requirements were last reviewed June 22, 2026; confirm the exact forms and fees with the local permitting authority.
A source-cited checklist of what an ADU (accessory dwelling unit) permit package needs in City of Detroit. Every item links to its authoritative source; items that vary are flagged to confirm locally.
ADUs became permitted by the 'Let's Build More Housing' Chapter 50 text amendment (signed 10/16/2025), by-right ONLY in the R2, R3, R4, R5, and R6 districts (explicitly NOT R1), accessory to a single-, two-, or small (≤3-unit) multiple-family dwelling; one ADU per zoning lot; gross floor area ≤ the smaller of 1,200 sf or 60% of the principal dwelling. The signed ordinance contains no owner-occupancy requirement, only a prohibition on rentals of 27 or fewer consecutive days. An applicant files a building permit (plus separate electrical/mechanical/plumbing trade permits) with BSEED; adding a dwelling unit may also require recording the change of use at the Wayne County Register of Deeds.
- Building Permit Application (Form P2)required
Completed building-permit application, filed via eLAPS/Accela.
source · reviewed 2026-06-22 - Details & General Notes Sheetrequired
Roofing system, masonry/concrete wall engineering & reinforcement, connection details, damp-proofing, and design dead/live loads.
source · reviewed 2026-06-22 - Electrical Planrequired
Separate electrical floor plan (fixtures, receptacles, switches, arc-fault protection); a separate electrical trade permit is also required.
source · reviewed 2026-06-22 - Elevationsrequired
All proposed elevations with materials, roof slopes/drains, attic ventilation, and hazardous-area safety glazing.
source · reviewed 2026-06-22 - Floor Plansrequired
Labeled rooms, doors, window sizes/types, egress windows/wells, attic/crawl access, garage-to-house fire separation, and stair details.
source · reviewed 2026-06-22 - Foundation Planrequired
Allowable soil bearing pressure, footing dimensions/depth, reinforcing, anchor bolts, and foundation details.
source · reviewed 2026-06-22 - Framing Plans (roof & floor)required
Size/spacing/span of all framing members, lumber grade/species, connections, and a headers/lintels schedule.
source · reviewed 2026-06-22 - Mechanical Planrequired
Separate mechanical plan: HVAC locations/capacity/fuel, registers, ductwork.
source · reviewed 2026-06-22 - Plot Plan / Site Planrequired
Lot size & shape, dimensioned property lines, all buildings, distances to property lines, streets & alleys, lot area, flood-plain status, and all utilities.
source · reviewed 2026-06-22 - Specificationsrequired
One set of specifications submitted for plan review.
source · reviewed 2026-06-22 - Structural Calculationsrequired
One set of structural calculations submitted with the plans.
source · reviewed 2026-06-22 - Three Complete Sets of Plans (to scale)required
Three complete plan sets drawn to scale, submitted for plan review.
source · reviewed 2026-06-22 - Trade Permits (electrical, mechanical, plumbing)required
Separate trade-permit applications (Forms C4/C3/C5) in addition to the building permit.
source · reviewed 2026-06-22 - Change-of-Use Recording (Wayne County Register of Deeds)conditionalverify locally
BSEED guidance: adding a dwelling unit may require recording the use change at Wayne County; exact applicability to a new detached ADU vs a conversion to confirm.
source · reviewed 2026-06-22 - Michigan Energy Code Compliance Worksheetconditional
Required for newly constructed dwellings (applies to new ADU construction).
source · reviewed 2026-06-22 - Truss Calculations (signed & sealed)conditional
Required when prefabricated trusses are used, and signed and sealed by a Michigan-licensed architect or engineer.
source · reviewed 2026-06-22
Detroit ADU permit questions
- Do I need a permit to build an ADU in Detroit?
- Yes. An accessory dwelling unit (ADU) in Detroit requires a building permit. ArchPermit tracks 16 cited requirements for this jurisdiction (13 required, the rest conditional). Always confirm the exact forms, fees, and code edition with the local permitting authority that issues the permit.
- What does an ADU permit package require in Detroit?
- Core required items include: Building Permit Application (Form P2); Details & General Notes Sheet; Electrical Plan; Elevations; Floor Plans; Foundation Plan, plus 7 more. Each requirement links to its authoritative source, and nothing is permit-ready until an independent licensed professional reviews and seals it.
- How are ADU permits submitted in Detroit?
- Detroit accepts permit submittals via eLAPS / Accela Citizen Access + ProjectDox. ArchPermit prepares a draft package you can submit there after a licensed architect reviews and seals it.