Bathroom Remodel Permit in Hazelwood, MO (2026)

Research by DoINeedAPermit Research Team · Updated May 2026

The Short Answer

A full bathroom remodel requires a permit if you relocate plumbing fixtures, add electrical circuits, install a new exhaust fan, or move walls. Surface-only updates (tile, vanity replacement in place, faucet swap) do not require a permit in Hazelwood.

Hazelwood follows the 2015 International Building Code and Missouri State Building Code, but the city's building department administers permits through a streamlined online portal and accepts over-the-counter applications for straightforward remodels — unlike some neighboring municipalities that require mail-in submissions or have longer plan-review windows. The City of Hazelwood Building Department explicitly separates cosmetic bathroom work (exempt) from structural, plumbing, and electrical changes (permitted), and this distinction is enforced at intake: if your project includes any fixture relocation, new circuits, ductwork, or waterproofing changes, you'll file a full Interior Remodeling permit, typically valued at 2–4% of the job cost. Hazelwood's frost depth of 30 inches and loess-based soil don't directly affect interior bathroom permits, but pre-1978 homes trigger lead-paint disclosure and containment rules if drywall or plaster is disturbed. The city does allow owner-builder permits for owner-occupied homes, which can save contractor licensing fees but requires the homeowner to pull permits and pass inspections personally. Plan for 2–4 weeks of plan review (electrical, plumbing, framing if applicable) and budget 3–5 inspections: rough plumbing, rough electrical, framing/waterproofing, drywall, and final.

What happens if you skip the permit (and you needed one)

Stop-work orders issued by Hazelwood Building Department carry $100–$300 fines per day; contractor work must cease immediately, costing you 1–3 weeks of delay and rescheduled inspections.
Unpermitted plumbing and electrical work voids insurance coverage for water damage and electrical fires; claims can be denied outright, leaving you liable for $5,000–$50,000+ in repairs.
Property disclosure on sale (Hazelwood buyers require disclosure of unpermitted work) or refinance will flag the bathroom remodel; lenders may require tear-out and re-inspection, costing $2,000–$8,000.
Double permit fees apply if work is discovered later: you'll owe the original permit fee plus a penalty fee of 50–100% of the original amount, typically $300–$800 total.

Hazelwood bathroom remodel permits — the key details

Hazelwood, like all Missouri municipalities, requires a permit whenever you alter the structure, mechanical systems, or electrical circuits of a bathroom — but not for cosmetic changes. The City of Hazelwood Building Department uses the 2015 IBC and 2014 NEC as the baseline code; however, the department adds local enforcement notes regarding GFCI/AFCI protection and exhaust-fan termination that differ slightly from state defaults. If your remodel includes moving a toilet, sink, or tub to a new location, you need a permit. If you're running new electrical circuits (a second outlet, a heated floor mat, a new light fixture on its own circuit), you need a permit. If you're installing a new exhaust fan or replacing the duct run, you need a permit. If you're converting a tub to a shower (which changes the waterproofing assembly per IRC R702.4.2), you need a permit. If you're moving drywall, removing a wall, or framing a new soffit for ductwork, you need a permit. Conversely, if you're replacing a faucet, toilet, or vanity in the same location — or retiling walls and floors without structural changes — Hazelwood treats that as cosmetic and exempt. The permit itself is filed on Form BLD-101 (or your city's equivalent form; confirm via the Hazelwood Building Department) and typically costs $150–$400 depending on estimated project valuation (usually 1.5–2% of labor plus materials, capped per the city's fee schedule).

Electrical work in bathrooms is tightly regulated under NEC 210.8 and enforced aggressively by Hazelwood inspectors. Every outlet within 6 feet of a sink, tub, or shower must be GFCI-protected (Ground Fault Circuit Interrupter); this can be a GFCI breaker in the main panel or an outlet-type GFCI. Additionally, any bathroom that has been substantially remodeled (per Hazelwood's local interpretation, this means any permit-level work) must have a dedicated 20-amp circuit for bathroom outlets, separate from kitchen or hallway circuits. If your remodel adds lighting or a heated towel rack, those often require their own 15-amp circuits. Hazelwood building inspectors will flag plans that show improper GFCI configuration or undersized circuits; rejections on this point are common and cost 1–2 weeks of revision. Your electrician should label GFCI protection clearly on the plan ('GFCI breaker at main panel, 20A circuit #7' or 'GFCI outlet at toilet, 20A circuit #8'), and the rough-electrical inspection will verify that every outlet has power and protection before drywall closes in.

Plumbing code in Hazelwood bathrooms falls under IRC Chapter 29 (Plumbing) and Missouri's adoption thereof. The most common code violations in Hazelwood bathroom permits are improper trap-arm length (the horizontal run between the trap and the vent stack cannot exceed 3 feet for a toilet or 2.5 feet for a sink per IRC P3201.7, depending on pipe diameter), inadequate slope on drain lines (minimum 1/4 inch per foot per IRC P3005.2), and missing or undersized vents. If you're relocating a toilet more than a few feet, the new drain line must be sloped correctly and vented within code limits; Hazelwood inspectors measure trap-arm length and slope angle during rough plumbing inspections. Vent stacks must penetrate the roof or connect to an existing vent stack within code distance; you cannot simply cap a drain or vent it through a wall in a modern code jurisdiction like Hazelwood. If your bathroom is on an upper floor and the existing vent stack is distant, you may need to tie into a wet vent (a vent that also drains, per IRC P3107) or install a new stack — a detail that often surprises homeowners and adds $500–$2,000 to the project. The rough plumbing inspection (typically scheduled after framing or immediately after demolition) will verify all drains, traps, and vents before water supply lines are connected.

Waterproofing and moisture control are critical for bathroom remodels, especially in tub-to-shower conversions. Hazelwood, under IRC R702.4.2 and Missouri Building Code amendments, requires a fully bonded waterproofing membrane under all shower and tub surrounds. The most common approved systems are cement board (like Durock or Hardiebacker) plus a liquid or sheet membrane, or fabric-reinforced waterproofing tape over drywall (less common, typically only for tub surrounds with alcove framing). If your plans show just drywall, tile, and grout without a specified waterproofing layer, Hazelwood plan reviewers will reject the plans and require you to specify a product (e.g., 'Schluter-Systems Kerdi membrane' or 'Mapei Aquadefense'). The final inspection includes a visual check of waterproofing and caulking; if grout is cracked or caulking is missing where walls meet the tub lip, inspectors may require remediation before signing off. This is one of the top reasons for failed final inspections in Hazelwood bathroom permits, so budget for a second inspection if caulking or grout work is marginal.

Ventilation (exhaust fans) is a source of frequent enforcement in Hazelwood. IRC M1505.2 requires that every bathroom with a tub or shower have an exhaust fan vented directly outdoors, delivering a minimum of 50–80 CFM (cubic feet per minute) depending on bathroom size. The duct must be rigid or semi-rigid (no flexible duct if avoidable), insulated if it passes through an unconditioned space, and terminated with a damper hood on the roof or exterior wall. Ductwork cannot terminate in an attic, soffit, or wall cavity; Hazelwood inspectors will reject plans that show this. If your bathroom is in a multi-story home and the duct must run a long distance (over 20 feet), ductwork upsizing and insulation become critical to prevent condensation and mold. Many Hazelwood homeowners discover during plan review that their attic or roof framing makes a simple duct run impossible, forcing a reroute or a second vent fan; this adds $300–$800 and 1–2 weeks of redesign. The rough-electrical inspection includes verification that the fan has a dedicated circuit (often 15A) and a humidity sensor or timer switch (some modern codes prefer timers to prevent stagnant air). The final inspection includes a visual of the exterior duct termination and a listening check that the fan operates quietly.

Three Hazelwood bathroom remodel (full) scenarios

Scenario A

Vanity and tile refresh, same plumbing locations — Hazelwood bungalow, 1950s

You're removing a 30-inch oak vanity and original porcelain sink from the wall, replacing it with a new 36-inch vanity with a ceramic sink, and retiling the floor and shower alcove with porcelain tile and new grout. The plumbing rough-in stays in the exact same location: P-trap, supply lines, and vent stack do not move. No electrical work is planned beyond confirming the existing light fixture and outlet remain. Hazelwood classifies this as cosmetic (or 'surface-only') work and does not require a permit. You do not need to file with the Building Department; you can proceed directly to purchase materials and hire a plumber and tile contractor. However, if your home was built before 1978, the city does require lead-paint disclosure and containment if you're removing drywall or disturbing painted surfaces (vanity backing, trim); this is not a permit, but a separate compliance check — hire a certified lead inspector if needed, or have your contractor use lead-safe work practices (drop cloths, HEPA vacuums). Material costs are roughly $3,000–$6,000 (vanity, sink, faucet, tile, labor). No inspections are required. Timeline: 1–2 weeks start to finish, no permitting delays.

Scenario B

Toilet and sink relocation, new exhaust duct — Hazelwood mid-range home, primary bath

You're gutting the bathroom, moving the toilet 4 feet to the opposite wall (new drain run required), and relocating the sink 2 feet left (new supply and drain lines). The existing exhaust fan is vented into the attic (code violation); you're replacing it with a new 80-CFM fan vented through a new insulated duct to the roof with an exterior damper hood. You're keeping the existing tub in place but stripping walls to studs and installing new drywall, cement board, and a tile surround with a liquid waterproofing membrane. The electrical panel is being upgraded with two new GFCI-protected 20-amp circuits: one for bathroom outlets, one for the exhaust fan and heated towel rack. This is a full Interior Remodeling permit, required by Hazelwood. You'll file Form BLD-101 with floor plans, electrical single-line diagram, plumbing riser, and waterproofing details (cement board + membrane specified by product name). Estimated project valuation: $15,000–$22,000 (materials + labor). Permit fee: $225–$350 (2–2.5% of valuation). Plan review: 10–14 days (electrical and plumbing focus). Rough plumbing inspection (after demolition/framing): verify trap arm length (must be under 3 feet for toilet), slope (1/4 inch per foot minimum), and vent stacks in code position. Rough electrical inspection: verify GFCI protection on all outlets and dedicated circuits. Waterproofing inspection (before tile): verify cement board and membrane installation. Final inspection: verify all systems operational and code-compliant. Timeline: 4–6 weeks total (permit intake + review + inspections + construction + final sign-off). Lead-paint disclosure required if pre-1978. Cost breakdown: permit $225–$350, plumbing rough-in $1,500–$2,500, electrical rough-in $800–$1,200, structural (framing/drywall/cement board) $2,500–$4,000, tile and finishing $2,000–$3,500, exhaust fan and duct $600–$1,000, fixtures and hardware $2,000–$3,000. Total: $10,000–$16,000 project cost (contractor), permit fees separate.

Scenario C

Tub-to-shower conversion, new waterproofing, no fixture relocation — Hazelwood older home, master bath

You have an original cast-iron tub in an alcove with tile walls and want to remove the tub and install a barrier-free (zero-threshold) shower pan with tile surround. The plumbing rough-in (P-trap, vent stack) remains in the same location; you're reusing the existing supply line and valve but adding a pressure-balanced cartridge valve rated for shower use per IRC P2709.1. The old tile and drywall backing are being stripped; new drywall, cement board, and a Schluter-Systems waterproofing assembly (Kerdi sheet membrane) are being installed. No electrical work. This is a tub-to-shower conversion, which Hazelwood treats as a code change requiring a permit because the waterproofing assembly changes (tub surround waterproofing differs from open-shower waterproofing per IRC R702.4.2). You'll file an Interior Remodeling permit with plumbing and framing details. Plan review will focus on the waterproofing specification (cement board + Kerdi membrane must be shown on plans) and the shower pan drain connection. Estimated project valuation: $8,000–$12,000. Permit fee: $120–$180. Plan review: 7–10 days. Rough plumbing inspection: verify P-trap is accessible, vent connection is within code limits, and supply line is cross-connected (no siphon). Waterproofing inspection (critical for this conversion): verify cement board and Kerdi membrane installation, including corners, seams, and termination at drain. Final inspection: verify tile grout and caulking are complete and watertight. Timeline: 3–4 weeks permitting + construction. Lead-paint disclosure required if pre-1978. Surprise: if the existing drywall behind the tub shows mold or water damage, you may be required to remove it and replace with moisture-resistant drywall; Hazelwood inspectors often discover this during framing inspection, adding $500–$1,500 and 1 week to the timeline. Cost breakdown: permit $120–$180, demolition and prep $600–$1,000, drywall and cement board $800–$1,200, Kerdi membrane and installation $500–$800, shower pan and drain $1,500–$2,500, tile and grout $2,000–$3,500, fixtures and finishing $1,500–$2,000. Total: $7,000–$11,000 project cost.

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Hazelwood's plan-review process: what to expect and how to avoid rejections

Hazelwood's inspection sequence for bathroom remodels typically unfolds in this order: rough plumbing (after framing/demolition, before walls close), rough electrical (same timing), waterproofing verification (after cement board/membrane installation, before tile), and final (after tile, grout, fixtures, caulking are complete). Each inspection requires 24–48 hours' notice to the Building Department; you call or email to schedule. Rough plumbing inspections focus on trap-arm slope, vent positioning, and material compliance (PVC, cast iron, or copper — no galvanized for drains); the inspector will measure and may use a slope gauge to confirm 1/4-inch-per-foot minimum. Rough electrical inspections verify that every outlet within 6 feet of water sources is GFCI-protected, that circuits are correctly sized and bonded, and that the exhaust fan has a dedicated 15-amp circuit. Waterproofing inspection (Hazelwood takes this seriously after several mold claims in the 2010s) checks that cement board is securely fastened, seams are taped with mesh, membrane is fully adhered and overlaps correctly at corners and penetrations, and that no drywall is exposed in wet areas. The final inspection is comprehensive: it checks fixture installation (toilet bolts tight, sink caulked, faucet functioning), GFCI outlets operating, exhaust fan drawing air, waterproofing integrity (no gaps or cracks), and aesthetic compliance (tile grout consistent, caulk smooth). Final inspection typically takes 20–30 minutes; if everything passes, you receive a Notice of Completion and can use the bathroom. If the inspector finds minor issues (caulk needs smoothing, one outlet GFCI not clicking), you'll get a punch-list and 5–7 days to correct; if issues are major (waterproofing failed, duct not vented properly), final inspection fails and you must correct and reschedule, adding 1–3 weeks.

Lead-paint compliance and pre-1978 bathroom remodels in Hazelwood

Hazelwood's 30-inch frost depth does not affect interior bathrooms directly, but it does affect any exterior ductwork, especially exhaust-fan ducts that exit through the roof or wall in climate zone 4A. Ductwork that passes through an unconditioned attic must be insulated to R-8 minimum (typically 1-inch rigid foam or similar) to prevent condensation during heating season; if condensation forms inside the duct, it drips back into the bathroom or pools in low spots, causing mold. Hazelwood plan reviewers and inspectors specifically flag uninsulated ducts in attics; if your plans show a bare duct running 20+ feet through an attic, expect an RFI requesting insulation specification. Additionally, duct termination on the roof must be sloped slightly away from the peak to prevent meltwater or rain from backing up; damper hoods (flapper vents) must be stainless steel or UV-resistant plastic to prevent freeze damage. In Hazelwood's loess-based soil, foundation settling can sometimes stress ductwork penetrations; if your bathroom is on a corner or above a crawlspace, the rough-electrical or framing inspector may ask about duct routing to avoid interference with settling or structural movement. Plan for duct insulation cost ($200–$400) and a roof-penetration flashing ($150–$300) if exhausting through the roof. If you vent through an exterior wall, ensure the duct slopes outward and terminates 12 inches minimum above grade to prevent water backup.

City of Hazelwood Building Department
Hazelwood City Hall, Hazelwood, Missouri (confirm exact address and hours with city)
Phone: (314) 838-7300 (Hazelwood main line; ask for Building & Code Enforcement) | https://www.hazelwoodmo.gov (permits section or online portal for building permits; confirm via city website)
Monday–Friday, 8:00 AM–5:00 PM (verify hours before visiting)

Common questions

Can I replace a toilet or faucet in my Hazelwood bathroom without a permit?

Yes. Replacing a toilet or faucet in the same location is considered cosmetic maintenance and does not require a permit. However, if you're relocating the toilet to a new position on the wall or floor, a permit is required because a new drain run and vent connection are needed. Similarly, if the existing faucet is failing and you're installing a new one in the same rough-in, no permit is required; but if you're moving the sink or adding a second sink elsewhere in the bathroom, you need a permit.

Do I need a permit to replace or add a exhaust fan in my Hazelwood bathroom?

Yes. Installing a new exhaust fan or replacing an existing fan duct (especially if rerouting the duct to the roof or exterior) requires a permit. Hazelwood code requires that the duct be properly sized (typically 50–80 CFM), insulated if passing through an unconditioned space, and terminated outdoors with a damper hood. If your existing fan vents into the attic (a common code violation), rerouting it outdoors is a permitted change. Simple replacement of a fan motor in an existing duct (ductwork stays the same) may be cosmetic, but confirm with Hazelwood Building Department first.

What does a typical bathroom remodel permit cost in Hazelwood?

Hazelwood permit fees for bathroom remodels are calculated as 1.5–2.5% of the estimated project valuation. For a $15,000 remodel (mid-range full gut with fixture relocation, tile, and ductwork), expect a permit fee of $225–$375. For a smaller remodel ($8,000, tub-to-shower conversion), expect $120–$200. Fees typically do not include inspection fees (inspections are included in the permit in Hazelwood), but you may pay separate fees for expedited review if requested.

How long does plan review take for a bathroom permit in Hazelwood?

Standard plan review in Hazelwood averages 7–14 days for bathroom remodels. If your plans are incomplete or contain code conflicts (e.g., missing GFCI specification, waterproofing system not named), Hazelwood will issue a Request for Information (RFI) within 5–7 days, and you'll have 10 days to resubmit revisions. If you resubmit promptly with corrections, expect approval within another 5–7 days. Expedited review (2–3 days) is sometimes available for an additional fee; contact Hazelwood Building Department to inquire.

Can I pull a bathroom permit as an owner-builder in Hazelwood?

Yes. Hazelwood allows owner-builders to pull permits for owner-occupied homes. You must be the legal homeowner and the permit must be in your name. You are responsible for passing all inspections and ensuring code compliance. Many homeowners hire a contractor but pull the permit themselves to save contractor licensing fees; however, you must personally coordinate inspections and be present during rough inspections. If you're unfamiliar with building code, consider hiring an engineer or consultant to review plans before submission to avoid RFI rejections.

What if I convert my tub to a shower in Hazelwood — do I need a permit?

Yes. Tub-to-shower conversions require a permit in Hazelwood because the waterproofing assembly changes (tub surround and open shower have different waterproofing details per IRC R702.4.2). You must submit plans showing the new waterproofing system (typically cement board plus a liquid or sheet membrane, e.g., Schluter Kerdi or Mapei Aquadefense), the shower pan and drain, and the valve specification (pressure-balanced valves are preferred for safety). Waterproofing inspection is a required stop before tile installation.

Are there any tricky Hazelwood code requirements I should know about for bathroom remodels?

Yes, a few common surprises: (1) Exhaust-fan ductwork must be insulated if it passes through an unconditioned attic (R-8 minimum), or condensation will form and cause mold — plan for $200–$400 in insulation. (2) Every outlet within 6 feet of a sink, tub, or shower must be GFCI-protected; this is enforced strictly at rough-electrical inspection. (3) Trap-arm length (the horizontal run from a toilet or sink P-trap to the vent stack) cannot exceed 3 feet for a toilet or 2.5 feet for a sink; if you're relocating a fixture far from the existing vent, you may need a wet vent or new vent stack, adding $500–$2,000. (4) Waterproofing systems must be specified by product name (not just 'waterproof membrane') or your plan will be rejected. (5) Pre-1978 homes require lead-safe work practices if you disturb paint or plaster; budget for lead containment ($500–$2,000) and have documentation ready for inspectors.

What inspections are required for a Hazelwood bathroom remodel permit?

A typical bathroom permit requires 3–4 inspections: (1) rough plumbing (after demolition/framing, verifies drains, traps, vents, and slope), (2) rough electrical (verifies GFCI protection, dedicated circuits, and bonding), (3) waterproofing (for tub-to-shower conversions or new tile surrounds, verifies cement board and membrane installation), and (4) final inspection (verifies fixtures, tile grout, caulking, and operational systems). If you're not moving walls or doing structural work, the framing and drywall inspections may be skipped. Schedule each inspection with the Hazelwood Building Department 24–48 hours in advance.

What happens if a Hazelwood bathroom remodel fails final inspection?

If final inspection fails, the inspector will issue a punch-list or 'Failed Inspection' notice citing code violations (e.g., grout cracked, caulk missing, GFCI outlet not functioning, exhaust fan not vented properly). You have 10–14 days to correct the issues and request a re-inspection. Minor issues (caulk, grout touch-ups) can usually be corrected in a few days; major issues (ductwork not vented, waterproofing failure) may require 1–3 weeks. Re-inspection is typically free if you corrected within 14 days; after 14 days, Hazelwood may charge a reinspection fee ($50–$100). Once all violations are cleared, the inspector signs off and issues a Notice of Completion, permitting you to occupy and use the bathroom.

Do I need a separate permit if I'm adding electrical circuits in my Hazelwood bathroom remodel?

No. Electrical work in a bathroom remodel is included as part of the Interior Remodeling permit; you do not pull a separate electrical permit. However, you must submit an electrical single-line diagram showing all new circuits, GFCI protection, and breaker assignments. If your electrical work is so extensive (e.g., full service upgrade or running circuits throughout multiple rooms), Hazelwood may require a separate electrical permit; clarify with the Building Department at intake. The rough-electrical inspection will verify all bathroom-specific code compliance (GFCI, dedicated circuits, proper bonding).

Disclaimer: This guide is based on research conducted in May 2026 using publicly available sources. Always verify current bathroom remodel (full) permit requirements with the City of Hazelwood Building Department before starting your project.

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