What's Required in Louisville
- A deck is exempt only if it is freestanding, up to 200 sq ft, no more than 30 in above grade and not serving the required exit door.
- Every attached deck needs a building permit from Construction Review.
- Permit fee: $50 plus $2.50 per $1,000 of estimated cost, $75 minimum.
- Footings in Jefferson County must reach at least 24 in below finished grade.
- Ledgers may not hang on stone or masonry veneer unless engineered or using a listed fastener.
- Deck wiring needs a separate Metro electrical permit.
- Deck work started without a required permit can draw a penalty equal to the permit fee.
Do You Need a Permit to Build a Deck in Louisville?
Usually yes. The Kentucky Residential Code (KRC), which Louisville Metro's Construction Review enforces, exempts a deck only when all four conditions hold: it is no more than 200 square feet, no more than 30 inches above grade at any point, not attached to the house, and does not serve the required exit door. Fail any one of them and you need a building permit. Every attached deck needs one, however low or small.
The old version of this page said decks under 30 inches that are not attached are usually exempt. That leaves out the 200 square foot cap and the exit-door test. It also gave a 30-inch frost depth. The KRC's Kentucky frost table lists specific counties and puts every county it does not name, Jefferson included, at 24 inches, measured from finished grade to the bottom of the footing.
Louisville Deck Permit Rules by Scenario
| What you are doing | City filing | Rule |
|---|---|---|
| Freestanding deck up to 200 sq ft, 30 in or lower everywhere, not at the exit door | None | KRC R105.2, Building item 9 |
| Any deck attached to the house | Building permit, $75 minimum | KRC R105.2; LMCO 150.096 |
| Freestanding deck over 200 sq ft | Building permit | KRC R105.2 |
| Any part of the deck more than 30 in above grade | Building permit | KRC R105.2 |
| Deck serving the home's required exit door | Building permit | KRC R105.2 and R311.4 |
| Adding deck lights or an outlet | Electrical permit, $75 or $100 | Fee schedule, Electrical item 3 |
| Footing depth in Jefferson County | 24 in minimum frost depth | KRC Table R403.1.4 |
How Much Does a Deck Permit Cost in Louisville?
Metro's promulgated fee schedule (LMCO 150.096, revised February 6, 2024) prices work whose square footage cannot be counted as floor area, including structures other than buildings, by estimated cost: $50 plus $2.50 per $1,000, and no building permit fee can be under $75. A $12,000 deck works out to $50 + $30 = $80. A $30,000 deck is $50 + $75 = $125, and a $40,000 deck is $150. Wiring for lights or a receptacle adds an electrical permit of $75 for work up to $750 or $100 above that. Building first and permitting later is expensive: the schedule allows a penalty equal to the standard fee.
What Do Inspectors Look For?
The Kentucky amendments touch decks in two places. The KRC lists the American Wood Council's DCA6 prescriptive deck guide among its accepted references, and its amended Section R507.2.2 bars hanging a deck ledger on stone or masonry veneer unless a design professional designs the connection or a listed fastening method is used. Footings must reach the 24-inch frost depth. Construction Review's own deck guide page could not be retrieved for this article, so ask the plan reviewer for the current checklist on guards, stairs and post sizes.
Who Can Apply?
Licensed contractors apply in the Louisville Metro Business Portal under the Residential Addition or Residential Alteration record types, which the portal lists. Its step-by-step guide says it offers the permit applications your license type allows. If you are building the deck yourself, call Construction Review at (502) 574-3321 to confirm how an owner files.
How to Get a Deck Permit in Louisville
Run the four-part test
Check size, height at every point, attachment and the exit door; failing any one means a permit.
Draw the plan
Show framing, footing depth of at least 24 in and the ledger connection; DCA6 is an accepted reference.
Estimate the cost
The fee is $50 plus $2.50 per $1,000 of your estimated cost, $75 minimum, verified by the department.
Apply with Construction Review
Contractors file in the Louisville Metro Business Portal; owners call (502) 574-3321 to confirm how to file.
Schedule inspections
Book the footing and final inspections, plus the electrical inspection if you added wiring.