ADU Permit Requirements in Grandville, MI
The City of Grandville (Kent County) contracts all building, electrical, mechanical, plumbing, and sign permits and inspections to Professional Code Inspections of Michigan (PCI), operating from its Jenison office, per the official cityofgrandville.com Community Development page. PCI is the enforcing agency, so the AHJ is the city (city_dept model) administered by a third party, not the State of Michigan. Permit applications are submitted through the PCI BS&A Online portal (Jenison uid 3129) or downloadable PDF forms. Residential work follows the 2015 Michigan Residential Code (2015 IRC base); the 2021 IRC update was filed effective Aug 29 2025 but remains enjoined by a Michigan Court of Claims order as of June 2026.
By Joey, Founder · Last verified June 4, 2026 · How we research →
When you need a ADU permit
MI (ZIP 49418), building an accessory dwelling unit requires a building permit under the 2015 Michigan Residential Code. The City of Grandville is the authority having jurisdiction and contracts permits and inspections to Professional Code Inspections of Michigan (PCI), its contracted inspector, at the Jenison office, (616) 667-8803. Submit 3 sets of plans with a floor plan, foundation plan, wall cross-section, truss drawings, and a 2015 energy compliance report through the PCI BS&A Online portal (uid 3129). Confirm that an ADU is permitted on your parcel with the City of Grandville.
ADU Permit Costs: Grandville vs. Nearby
| City | Estimated Fee |
|---|---|
| Grandville | N/A |
| Detroit | $500 – $5,000 |
| Grand Rapids | $500 – $5,000 |
| Warren | $500 – $5,000 |
Fees shown are estimates based on local building code data. Actual fees may vary based on project scope and valuation. See all Grandville permit costs →
Zoning Considerations
ADU regulations vary dramatically by state and city. Many states (CA, OR, WA) have preemption laws that override local zoning restrictions. Check both state law and local zoning before designing.
Estimated Project Timeline
Here's a typical timeline for a adu project:
Timeline is based on the typical about 3 weeks permit processing time. Actual timelines vary by project complexity, completeness of application, and current department workload.
Need an ADU permit?
Answer a few quick questions for a personalized answer about your specific project.
Check Now, Free →Building Department Contact
Frequently Asked Questions
Contact the building department for current ADU permit fee information. Fees typically vary based on project scope and valuation.
It depends on the specifics of your project. Some smaller ADU projects may be exempt from permit requirements, while larger ones typically require a permit. Use our free lookup tool to check your specific situation.
Working without a required permit can result in fines, stop-work orders, being required to remove completed work, and complications when selling your home. It's always best to check first.
Typical approval time for ADU permits is about 3 weeks. More complex projects may take longer if plan review is required.
Learn More About ADU Permits
Read our complete guide covering permit requirements, costs, common exemptions, and the application process.
Read ADU Guide →