Is an Engineer Required for My Deck Project in Kentucky?

Kentucky cities — Louisville, Lexington, Bowling Green, Owensboro — generally require an engineer-sealed plan set for any deck that leaves the prescriptive path, and the PE seal is the standard requirement for the structural sheets. The seal must show the engineer's name, Kentucky PE number, and date, with the engineer in responsible charge. Simple ground-level decks can often be permitted from the prescriptive span tables, but ledger-attached decks, decks over 30 inches above grade, and decks carrying a hot tub or roof load are treated as engineered work in Kentucky. Owner-builders don't escape the requirement: the building department asks for the seal regardless of who drew the plans, and the engineer must design the deck for karst terrain and New Madrid seismic risk.

The engineer designs the footings for footings probed for karst voids — the engineer confirms bearing ground before piers are poured over sinkhole-prone lots, and details the ledger connection with ledger with seismic lateral ties in the west — New Madrid forces reach decks, so the engineer details positive house connections. Guards, stairs, and lateral bracing go on the sealed plan set — guard height and infill spacing, stair stringer sizing, and the bracing that keeps the deck from racking under karst terrain and New Madrid seismic risk. Bring a plot plan with setbacks, the deck's dimensions and height above grade, and photos of the house wall where the ledger will attach. Kentucky karst can swallow a deck footing — the engineer verifies the ground carries each pier before the frame goes up.

Use this checklist before engaging an engineer for your deck: • Engineer of record holds an active Kentucky PE license, verifiable on the state roster • Footings designed for karst terrain and New Madrid seismic risk on the lot • Ledger connection detailed to the house band joist, never the veneer • Lateral bracing and hold-down designed for karst terrain and New Madrid seismic risk • Guards and stairs drawn to code (guard height, infill spacing, stringers) • Hot tub or roof loads called out and framed for where the deck carries them • Post bases and hardware specified for the local exposure • Engineer confirms they'll respond to plan-check corrections on sealed sheets