Do I need a permit for a full bathroom remodel in
Farragut, Tennessee?

Farragut bathroom remodel permits — the key details

Farragut's permit requirement hinges on what you're changing. Per IRC P2706 (Drainage Fittings), any relocation of a toilet, sink, or tub drain triggers the permit threshold. The same applies to supply-line relocation, per IRC P2903 (Water Supply and Distribution). A full gut remodel almost always involves moving at least one fixture — typically the vanity or toilet — and therefore requires a permit. The City of Farragut Building Department will ask you to submit a site plan (showing the bathroom location within the home), architectural plans (wall layout, fixture locations to scale), plumbing plans (supply and drain routing with trap-arm lengths clearly labeled), and electrical plans (outlet locations, GFCI/AFCI specifications, and new-circuit requirements if you're adding outlets or lighting). The most common rejection point is incomplete waterproofing detail: if you're converting a tub to a shower or vice versa, IRC R702.4.2 requires a water-resistive membrane behind the finished surface. You must specify the system (cement board + liquid membrane, schluter kerdi, or equivalent) and note the membrane overlap and sealant details. Farragut inspectors will not approve rough framing until this is documented on the plan. Many homeowners submit plans showing only 'waterproofing per code' and then receive a request for revision; including a 1–2 sentence spec on your initial submission avoids the back-and-forth.

Electrical work in a bathroom remodel is heavily regulated and is the second-largest source of plan rejections. Per NEC 210.52(A) and IRC E3902, every bathroom must have a GFCI-protected outlet within 36 inches of the sink. If you're adding a new exhaust fan, that circuit must also be on GFCI protection. Many contractors and homeowners assume old bathrooms are grandfathered in, but Farragut requires GFCI retrofit as part of any remodel that touches the electrical system — if you're adding a new circuit for a heated mirror or additional lighting, the entire bathroom must now meet current code, including GFCI. Additionally, if your bathroom is on the same circuit as lights or other loads, IRC E3903 requires an AFCI (Arc Fault Circuit Interrupter) for the lighting circuit. Your electrical plan must show all outlets, switches, fixture locations, and a clear statement of which circuits are GFCI and which are AFCI. A single-line diagram is often sufficient; however, Farragut's Building Department has been known to request a detailed panel schedule if the remodel involves more than one new 20-amp circuit. Plan for this in your timeline — revisions can add 7–14 days.

Exhaust ventilation is required per IRC M1505 (Ventilation Required) and is triggered if you're installing a new exhaust fan or upgrading an existing one. The duct must terminate to the outside (not into the attic; Farragut inspectors are strict about this) with minimum 3-inch or 4-inch diameter flex or rigid duct. Duct must slope downward slightly toward the exit to prevent condensation pooling. Exhaust fan cubic feet per minute (CFM) is determined by bathroom square footage: a 40-square-foot bathroom requires 40 CFM, a 70-square-foot bathroom requires 70 CFM (or 1 CFM per square foot as a rule of thumb). If your bathroom is in a smaller home or you're reluctant to run duct to an exterior wall, a through-roof termination is permitted but is more expensive and can create roofing penetration issues — many Farragut homeowners opt to rough the duct to the soffit instead. Your plan must show the duct routing, termination location, damper (required, per IRC M1505.2), and the CFM rating of the fan. Missing damper spec is another common rejection. The Farragut Building Department will assign a separate inspection for the duct after rough framing; plan 2–3 additional inspection appointments beyond the standard plumbing and electrical rough-ins.

Plumbing trap and vent routing is governed by IRC P3103 (Pipe Sizing) and IRC P3105 (Vent Sizing). If you're moving a toilet, the drain must slope 1/4 inch per foot toward the main stack, and the trap arm (the horizontal section between the toilet and the vent) cannot exceed 6 feet in length per IRC P3201. This is a major issue in older Farragut homes where bathrooms are far from the main vent stack — if your toilet is more than 6 feet from the nearest vent, you may need to install an island vent (a small vent that runs up through the vanity or wall) or relocate the fixture. These vents are visible and ugly, and many homeowners are unaware of the constraint until the plumber submits the plan. Discuss trap-arm length with your plumber before finalizing the design. For sink drains, the trap arm is also limited (typically 5 feet), and double vanities often require separate drains or a common vent — again, something to nail down early. Farragut inspectors will measure trap-arm length in the field during rough plumbing inspection and will mark work as 'failed' if it exceeds code. This is non-negotiable and will require cutting and rerouting.

The permit timeline in Farragut typically spans 3–5 weeks from submission to final sign-off. Initial plan review (5–10 business days) will produce a marked-up set with deficiencies; you resubmit with corrections (2–3 days if your contractor is responsive), then a second review (3–5 business days) approves or requests final minor revisions. Once approved, you schedule rough plumbing (1 business day for inspection availability), rough electrical (1–2 days later), rough-in framing or drywall (if walls are moved), exhaust-duct inspection (1–2 days), and final inspection (1–2 days). If the inspector finds non-compliant work (e.g., trap arm too long, missing GFCI outlet), you must remediate and re-inspect, adding 3–7 days. The permit itself is valid for 180 days, so if your contractor stalls, you're not penalized immediately, but the project must be substantially complete and all inspections passed within that window. The City of Farragut Building Department does issue extension permits (usually for $50–$100), but it's better to maintain momentum and complete inspections sequentially.

Three Farragut bathroom remodel (full) scenarios

Farragut's waterproofing assembly requirement for tub-to-shower conversions

When you convert a tub to a shower, you're changing the exposure of the bathroom envelope. A bathtub acts as a barrier; the tile and grout above it only see splash. A shower stall is fully wet: the walls, corners, and substrate are constantly exposed to water and steam. IRC R702.4.2 mandates a water-resistive membrane for shower walls that extends from the top of the bathtub rim (or the shower base) at least 72 inches up (or to the top of the enclosure if higher). Farragut's Building Department has clarified this in past permit rejections: they require either (a) cement board + liquid waterproofing membrane (RedGard, Hydro-Ban, or equivalent, applied per product spec with 6-inch overlaps), or (b) a waterproofing sheet system (Schlüter Kerdi, Wedi boards, or approved pre-fabricated panels). Drywall with a vapor barrier is NOT acceptable; the inspector will reject it on rough framing inspection.

The distinction matters because Farragut has karst geology (limestone bedrock, some subsurface moisture), and past mold claims in poorly waterproofed bathrooms have prompted the city to tighten enforcement. Your plan submission must include a 1–2 sentence spec: 'Shower walls: 1/2-inch cement board on studs, RedGard liquid membrane applied per manufacturer, minimum 6-inch overlap at seams and corners, sealed with epoxy grout.' If you're unsure, email the plan to Farragut Building Department before formal submission and ask for waterproofing pre-approval. This takes 2–3 business days and saves a rejection cycle.

Cost implications: cement board + RedGard adds $400–$800 to the material and labor budget (vs. drywall). Schlüter Kerdi boards add $600–$1,200 because they're more expensive but faster to install. If your contractor suggests drywall with a plastic sheet or tape, push back and insist on code-specified membrane. The long-term savings (no mold, no wall rot, no insurance claim) far outweigh the upfront cost. Farragut inspectors do inspect waterproofing during rough framing — they'll visually confirm it's in place — and again at final if they have concerns.

Knox County karst geology and bathroom plumbing considerations

Farragut sits in Knox County, which is underlain by Ordovician limestone (karst terrain). While most bathroom remodels do not involve subslab plumbing, if your project includes a new floor drain, sump pump, or drain-line routing through the basement or foundation level, karst drainage patterns matter. Limestone is porous and can have sinkholes, collapsed cavities, and variable settlement. The Knoxville-area United States Geological Survey (USGS) map shows scattered karst features across Knox County, including some in Farragut subdivisions. This does not automatically trigger bathroom-code amendments, but it means your plumber should confirm that floor drains slope correctly toward a foundation drain or sump (not toward a subslab void). Farragut's Building Department does not have a special karst overlay ordinance, but local plumbers familiar with the area know the quirks.

If you're moving a toilet drain and the route includes a basement run, discuss slope and settlement risk with your plumber. A 1/4-inch-per-foot slope is code minimum, but in karst areas, settling soil can create low spots over time, causing slow drains or pooling. Some Farragut contractors recommend PVC or no-hub cast-iron for subslab runs (vs. flexible ABS) because rigid pipe resists settlement better. The Building Department will not reject your plan for choosing rigid vs. flexible, but it's a best-practice discussion. Frost depth in the Farragut area is 18 inches, which is relevant if your drain leaves the foundation below that depth — no special requirement, but standard practice.

A final note: if your project abuts a limestone retaining wall or if your lot has visible sinkholes, consult with a geotechnical engineer before proposing a major plumbing reroute. This is rare for bathroom remodels, but it's a safeguard in karst terrain. Farragut Building Department staff can point you to local engineers if needed.

Common questions