What happens if you skip the permit (and you needed one)
- Stop-work order plus $250–$500 fine from Troy Building Department; if the city inspects unpermitted work, you cannot legally occupy the space until permits are pulled retroactively, which costs 1.5-2× the original permit fee ($400–$1,200 total).
- Home sale disclosure: Michigan requires sellers to reveal unpermitted work on the Property Disclosure Statement; buyers can demand $5,000–$15,000 reduction or walk entirely, or require owner-funded remediation before closing.
- Mortgage refinance or title-insurance claim denial: lenders run title searches and flag unpermitted structural/habitability work; you lose refinance eligibility until permits are corrected retroactively ($800–$2,000 in re-permit and inspection fees).
- Insurance claim rejection if water damage or fire occurs in the unpermitted basement space; homeowner's policy explicitly excludes claims in spaces that violate building code.
Troy basement finishing permits — the key details
Troy permit fees scale by estimated project valuation: $200–$400 for a storage/utility basement (non-habitable, minimal electrical), $300–$600 for a basic family room or rec room (habitable, no bath), and $600–$1,000 for a bedroom + bathroom finish. The city calculates valuation as roughly 50-70% of contractor bid or 60-80% of square-footage-based estimates (typically $50–$80 per square foot for finished basement in Troy). If you're doing a 600-square-foot basement finish with bathroom and bedrooms, the city might estimate $30,000–$40,000 valuation, yielding a $600–$800 permit fee. You can appeal the valuation at intake if you think it's inflated, but the cost difference rarely makes a fight worthwhile. Plan for these line items: building permit ($300–$600), electrical permit ($150–$300), plumbing permit ($100–$300 if there's a bathroom), and potential mechanical permit ($50–$150 if HVAC is added). Total permit fees: $600–$1,350 for a full finish with bath. Additionally, radon-system roughing and egress-window installation (if retrofitting) are not permit costs but construction costs that must happen before final inspection.
Three Troy basement finishing scenarios
Egress windows and radon mitigation: Troy's two non-negotiables
Radon mitigation readiness is a Michigan State Code requirement that Troy enforces at permit close-out, and many homeowners encounter it for the first time during rough-electrical inspection. The rule: all basement permits must include a rough 3-inch or 4-inch PVC pipe running from the basement slab (with a cap or boot to collect soil gas) vertically through the rim joist and through the roof, terminating at least 12 inches above the roofline. The system does not include a fan initially (that's a future option), but the pipe must be in place and accessible so a radon-mitigation contractor can add a fan without breaking walls. Cost is typically $300–$800 for rough material and labor. On the electrical plan, you must label this pipe and confirm its location to the inspector. During rough inspection, the city inspector will verify that the pipe is installed, sealed at penetrations, and clearly visible. If it's missing, the permit cannot proceed to final inspection. This is not negotiable, even in basements with no known radon history; it's a state-level requirement that Troy enforces uniformly across all basements. The reasoning: Michigan has moderate to high radon risk in many counties, including Troy's location in Oakland County (Zone 1-2 per EPA radon-potential maps), so passive mitigation readiness is standard practice.
Moisture, ejector pumps, and below-grade plumbing in Troy's glacial-till soil
One often-overlooked requirement: if you finish your basement and later sell your Troy home, Michigan's Property Disclosure Statement (PDS) requires you to reveal all basement-moisture history and any remediation work. If an inspector finds unpermitted plumbing or an unpermitted ejector pump, the buyer can demand remediation before closing or walk away entirely. For this reason, pulling permits for below-grade plumbing is not optional — it's a title-insurance issue. If you skimp and install a bathroom without an ejector pump or without a permit, you risk a sale falling apart at inspection, or a later buyer suing you for undisclosed water damage. Troy's building department is particularly strict about this because the city has experienced several high-profile cases of unpermitted basement water damage claims. The best practice: if you have any doubt about water history or future moisture risk, hire a foundation engineer to evaluate your lot and basement for a $400–$600 assessment before finalizing your finish plan. This assessment often qualifies you for a lower insurance premium and clears the path for a faster permit review.
100 W. Big Beaver Rd., Troy, MI 48084
Phone: (248) 520-2541 (main) or (248) 520-2435 (permits line) | https://www.troymi.gov/ (select Building Permits under Departments or Permits & Inspections)
Monday–Friday, 8:00 AM–5:00 PM (closed holidays)
Common questions
Does Troy allow owner-builder permits for basement finishing?
Yes, Troy allows owner-builder permits if you are the owner-occupant of the property and you occupy it as your primary residence. You must apply in person at City Hall, bring proof of ownership and occupancy, and you can only use the owner-builder exemption for one property at a time. However, plumbing and electrical work almost always require licensed contractor involvement; you cannot install wiring, circuits, or plumbing yourself in Troy. The owner-builder exemption covers framing, drywall, and structural finishes only. For electrical and plumbing, hire licensed trades. Contact the Building Department for the owner-builder application form.
Can I finish my basement without an egress window if I don't plan to use it as a bedroom?
Technically yes, if you can prove the room will never be a bedroom. However, Troy's inspector will note in the permit that the space is non-egress and cannot be legally marketed or used as a bedroom. If you later want to convert it to a bedroom, you must stop work, add the egress window, and get re-approval. Many homeowners avoid this hassle by installing the egress window upfront — it costs $2,000–$5,000 but preserves future flexibility and resale value. If the room will be a family room or recreation room only, no egress is required.
How long does a basement finishing permit take in Troy?
Plan review typically takes 3-5 weeks from initial submission. Simple family-room projects might clear in 2 weeks; projects with bathrooms or moisture history often go 4-5 weeks due to one or more revision cycles. Once the permit is issued, inspections happen over 3-5 weeks running concurrent with construction (framing, rough trades, drywall, final). Total project timeline from filing to final inspection: 6-10 weeks on average. Expedited review is not offered for residential basements.
What if my basement has a concrete floor but no sump pit — do I need one?
Only if you are installing plumbing fixtures (toilet, sink, shower) below the main sewer line. If you're finishing the basement with only drywall, flooring, and electrical outlets (no fixtures), you do not need a sump pit from a code perspective. However, if your lot has water-intrusion history or sits in a high water-table zone, the permit reviewer may require a sump pit as a moisture-control measure even without plumbing. When you apply for the permit, disclose any water history honestly; the reviewer will advise whether a pit is required.
Does Troy require radon testing before finishing a basement?
Troy does not require radon testing before you finish a basement, but the permit requires a radon-mitigation-ready rough-in: a PVC pipe from the slab to the roof. This allows future radon mitigation without walls being damaged. The EPA recommends radon testing in Michigan basements (Oakland County is Zone 1-2 radon risk). If you want to test, hire a certified radon tester ($150–$300) and test for at least 48 hours. If levels exceed 4 picocuries per liter, you should activate the radon system (add a fan, $1,200–$2,500) after the rough-in is approved.
Can I pull a permit for just the electrical work and skip building and plumbing?
No. If you are creating habitable space (bedroom, bathroom, family room), all three permits are required: building, electrical, and plumbing (if applicable). They are filed together and reviewed together. You cannot do electrical work without a building permit for a habitable-space finish. If you are adding a single outlet to non-habitable storage, you can pull an electrical permit alone ($75–$150).
What is the estimated cost of a full basement finish with bathroom in Troy?
A 600-800 sq ft basement finish with bedroom, bathroom, and egress window typically runs $25,000–$45,000 in total construction cost (framing, drywall, flooring, egress retrofit, electrical, plumbing, HVAC integration, painting, fixtures). Permit fees are $600–$1,000 on top of that. If you have water-intrusion history or need a full perimeter drain, add $2,000–$5,000. Egress-window retrofit alone is $2,000–$5,000. Labor costs vary; get three bids from Troy-licensed contractors. Electrical and plumbing permits are $300–$600 combined.
What happens at the rough electrical and rough plumbing inspections?
Rough electrical: the inspector checks that all wires are in conduit or Romex, boxes are installed, circuits are correctly labeled, AFCI and GFCI breakers are in place, and the radon-mitigation pipe is labeled and visible. Rough plumbing: the inspector confirms all drain lines are pitched to the ejector pit, the ejector pump is installed and accessible, vent pipes are sized and routed, and there are no code violations. Both inspections happen before drywall is closed. If violations are found, you get a written list and must correct them before final inspection. Corrections usually take 3-5 business days.
Does Troy require smoke and CO detectors in a finished basement?
Yes. IRC R314 requires interconnected smoke alarms on every level, including the basement if finished as habitable space. CO detectors are required within 15 feet of any fuel-burning appliance (furnace, water heater). In a basement bedroom, a smoke alarm must be installed in the bedroom and in the hallway outside the bedroom, and they must be wired together (hardwired, not battery). Many homeowners opt for wireless interconnected detectors ($20–$40 per unit, 4-6 units typical) to avoid running electrical wire. The final inspection includes verification that detectors are installed and operational.
Can I use a basement bedroom if the permit is not yet final?
No. Legally, you cannot occupy a basement as a bedroom until the final inspection is passed and the permit is closed. If you move in before permit close, you risk a complaint from a neighbor or discovery during a subsequent inspection, which can trigger a stop-work order and fines. The final inspection verifies the egress window is functional, all required safety equipment is in place, and all code violations are corrected. It typically takes 5-10 business days to schedule after rough inspections are passed. Do not move in early.