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Deck building across the Kansas City area
We build new decks, repair existing ones and replace decks that have failed in ten communities on both sides of the state line. The construction is the same wherever we work, but each city decides when a deck needs a permit, how deep its footings go, how close it can sit to a property line, which inspections it gets and who can hold the permit.
This page explains how those rules vary and links to a page for each community. For the work itself, see new deck construction, deck repair, deck replacement or the full services directory.
How deck rules differ from city to city
Every city we serve bases its deck rules on the International Residential Code. Most enforce the 2018 edition with local amendments, and St. Joseph's Building Division states that it reviews residential plans against the 2024 edition.
Footing depth
Footings have to bear below the frost line so freezing and thawing soil can't lift them. Kansas City, Missouri's Code of Ordinances sets frost depth at 36 inches, and Olathe, Overland Park, Grain Valley, Harrisonville, Smithville and Leavenworth use the same depth, with Leavenworth adding a 12-inch minimum footing width. Lawrence's amended code sets its frost line at 30 inches. St. Joseph applies its 36-inch depth to decks attached to a structure with frost-protected footings and to decks over 600 square feet.
When a permit is required
Permit thresholds vary more than footing depths:
- Kansas City, Missouri: a deck is exempt only when it's no more than 30 inches above grade at any point and isn't over a basement or a story below.
- Olathe, Overland Park and Harrisonville: a deck is exempt only when it's detached, no larger than 200 square feet, no more than 30 inches above grade and not serving the required exit door.
- Lawrence: an uncovered deck is exempt only when it's no more than 30 inches above grade, not over a basement or a story below and not part of an accessible route.
- Belton: every covered deck needs a permit, and an uncovered deck needs one once it's more than 30 inches above grade.
- Grain Valley: a deck needs a permit above 30 inches or when it's attached to the house at any height, and the city's deck brochure requires permits for all new or replaced decks.
- St. Joseph, Smithville and Leavenworth: none of the three publishes a size or height below which a deck skips the permit, and St. Joseph's amendments delete the code's exemption list entirely.
An exemption covers the permit only. Kansas City's and Harrisonville's codes both state that it doesn't authorize work that violates the code.
Setbacks and easements
Kansas City lets a deck under 500 square feet on a detached house extend into the rear setback, as long as a rear setback of at least 20 feet remains. Overland Park has a 25-foot rear setback that open decks can project into by up to 6 feet, with the encroaching area capped at 60 square feet. Smithville lets decks and porches extend into a required yard by no more than 30 percent of that yard's depth. Lawrence keeps decks out of minimum setbacks entirely, though uncovered stairs and landings may project if they stay 3 feet from every property line. Grain Valley and Lawrence both prohibit decks on or over easements. On many lots, these lines set the deck's maximum size.
Licensing and inspections
Who can hold the permit is also set locally. Overland Park and Olathe issue permits only to contractors with an active Johnson County contractor's license, Kansas City, Missouri requires a residential building contractor license, and Lawrence and Smithville each require their own city license. Inspections vary as much. Belton inspects the open pier holes and the finished deck, Lawrence adds framing and rough-in electrical inspections, and Overland Park inspects footings only on covered decks.
City limits, mailing addresses and county rules
A mailing address doesn't always tell you which office reviews a deck. Kansas City, Missouri stretches across parts of Jackson, Clay, Platte and Cass counties and borders separate cities such as North Kansas City, Gladstone, Raytown, Grandview and Independence, each with its own building department. A "Kansas City, MO" address can sit outside KCMO's city limits.
The same applies at the edges of smaller towns. Property inside Harrisonville's city limits goes through the city under the 2018 code, while property outside them falls under the Cass County building codes office, whose deck packet is based on the 2006 code and requires a permit for every deck attached to the house or 30 inches or more above grade. The code edition, permit threshold and inspections all follow the jurisdiction.
Historic districts and older neighborhoods
Several of our communities add a review step for historic properties. Kansas City requires a certificate of appropriateness for exterior alterations visible from a public place on a designated landmark or in a historic district. Harrisonville requires a Certificate of Appropriateness before a building permit for work on a designated landmark or in a local historic district. Lawrence forwards permit applications for landmarks, historic districts and their environs to its Historic Resources Commission. Leavenworth lists eight historic districts, and St. Joseph's Landmark Commission reviews visible work in its local districts.
Housing age matters too. Census Bureau estimates put the median year built at 1962 in St. Joseph and 1969 in Kansas City and Leavenworth, against 2002 in Grain Valley. On older houses, the existing deck was built to rules that have since changed, and the wall wasn't always built to carry a modern ledger.
Our service area, city by city
Belton, MO
Belton's Deck/Patio Project Information sheet asks for structural sizes up front. The Belton page covers the sheet, its two inspections and the city's footing and ledger rules.
Grain Valley, MO
The Grain Valley page covers the city's amended code, the guard, stair and handrail dimensions in its deck brochure, and easements and HOA covenants.
Harrisonville, MO
The Harrisonville page covers the city's four-part deck exemption, the split with Cass County, its local code values and historic review.
Kansas City, MO
The Kansas City page covers the height-based exemption, inspections, the rear-setback allowance, historic districts and floodplains.
Lawrence, KS
The Lawrence page covers the permit application, the 30-inch frost depth, setback and easement rules and the four inspections.
Leavenworth, KS
The Leavenworth page covers the combined deck and porch permit, the 36-by-12-inch footing minimum and the city's historic districts.
Olathe, KS
The Olathe page covers Johnson County licensing, what a deck plan has to show and how the city inspects decks.
Overland Park, KS
The Overland Park page walks through the July 2026 deck guidelines: permit plans, setbacks, ledgers and inspections.
Smithville, MO
The Smithville page explains the structural charts in the city's deck guidelines, the footing inspection and the yard limits.
St. Joseph, MO
The St. Joseph page covers the Deck and Deck Roof checklist, the code edition and the city's historic design guidelines.
Questions about our service area
Does a Kansas City mailing address mean KCMO rules apply?
Not always. The permit office is set by the jurisdiction the property sits in, which may be a neighboring city with its own building department or, at the edges of smaller towns, the county.
Can a deck plan from one city be used in another?
Only after it's checked against the new city's rules. Footing depth, permit thresholds, setbacks and code edition can all change the design.
Does replacing a deck mean meeting today's rules?
Usually. Overland Park and Lawrence require a permit to replace a deck, and the Johnson County guideline Olathe follows says the same. Where a permit applies, the new deck is reviewed against current code and setbacks, so a deck built into a Lawrence setback years ago can't simply be rebuilt in the same footprint.
KC Deck Builds is locally owned, licensed and insured, and serves homeowners across the Kansas City area with new decks, repairs and replacements. Call (913) 687-7031 for a deck estimate.