· by Michael Blair, Nashville's Cabinets
An island is often the first thing a homeowner asks for and the last thing that fits. On paper it is a rectangle in the middle of the kitchen. In the room it is the thing everyone walks around, sits at and opens the dishwasher into, and an island a few inches too big turns a working kitchen into a series of tight squeezes. Before we draw custom cabinets for an island, we check the plan against two references: the National Kitchen and Bath Association’s planning guidelines, which are recommendations, and the residential code, which is not. Here is what each says and how we use it.
How much floor should an island leave around it?
Plan at least 42 inches between the island and the facing counter if one person cooks, and at least 48 inches if two people often cook at once. Those are the work aisle widths in the NKBA’s Kitchen Planning Guidelines with Access Standards, measured between the fronts of the counters, tall cabinets or appliances, not between the cabinet boxes. A side of the island that is only a pass-through, with no work happening along it, can be a walkway instead, and the NKBA recommends at least 36 inches for that, or 42 inches for one of them where two walkways meet at a right angle.
Those numbers are where the size of an island really comes from. Take the room’s width, subtract the counters on each side and the aisles you need, and what remains is the island. When an owner wants a bigger island than the room allows, we would rather shorten it or drop a row of seats than cut an aisle below the NKBA figures, because a tight aisle shows up every day and a slightly smaller island rarely does.
How much space does seating at an island take?
Each stool needs a knee space about 24 inches wide, and the depth of knee space under the overhang depends on the counter height. The NKBA guidelines ask for a knee space 24 inches wide by 18 inches deep for each diner at a 30-inch table height, 24 by 15 inches at a 36-inch counter, and 24 by 12 inches at a 42-inch bar height. The higher the counter, the less room the knees need, which is why bar-height seating can work on a narrower island.
The floor behind the stools matters as much. The NKBA asks for 32 inches from the counter edge to a wall or other obstruction where nobody passes behind a seated diner, at least 36 inches if people need to edge past, and at least 44 inches to walk past. Seats facing a busy path to the back door or the refrigerator need the larger figure, and that often decides which side of the island gets the stools.
Can you put a cooktop in a kitchen island?
Yes, but it brings its own clearances. The NKBA recommends at least 12 inches of landing space on one side of a cooking surface and 15 inches on the other, and for safety in an island or peninsula it says the countertop should extend at least 9 inches behind the cooking surface when the counter and the cooktop are at the same height. That strip behind the burners keeps a pot handle and a seated guest from being in the same place. The guidelines also recommend a correctly sized, ducted ventilation system for every cooking surface.
Anything built above an island cooktop is a code matter. Section G2447.5 of the residential code, which reads the same in Tennessee’s 2018 residential code and in Nashville and Davidson County’s 2024 residential code, requires at least 30 inches of vertical clearance above the cooking top to combustible material and metal cabinets. It allows 24 inches only where the underside is protected with insulating millboard covered in sheet metal, where a metal hood of at least the appliance’s width is centered over it, or where a listed appliance is installed over a listed cooking appliance under the maker’s instructions. A wood hood surround or a decorative beam over an island falls under that rule. The section sits in the fuel gas chapter, so it governs gas cooktops; an electric or induction unit follows its own installation instructions, which we read before the hood is drawn.
Drawing the island before it is built
We mark the island’s outline on the floor with tape before anything is ordered, mark how far the dishwasher, oven and refrigerator doors swing toward it, and walk the paths a household actually uses. Metro Nashville’s 2024 codes apply to plans and applications submitted after July 16, 2025, according to Metro Codes’ announcement of the 2024 adoption, and outside Davidson County the local codes office says which edition it enforces, so the codes office where you live has the final word on anything electrical, gas or plumbing that goes into the island. A cooktop, a sink or new outlets usually mean a permit, and we plan the cabinet around the trades rather than the other way around.
Whether the island should be built from scratch or from standard boxes is its own question, and our comparison of custom and stock cabinets covers it. We build islands for kitchens in Mt. Juliet and the rest of Wilson County, and across Middle Tennessee. To start one, send us a sketch of the room with its measurements, and mark where the windows, doors and appliances sit.
Sources
- National Kitchen and Bath Association, Kitchen Planning Guidelines with Access Standards — Work aisle 42 and 48 inches; walkway 36 inches, 42 where perpendicular; clearance behind seated diners 32, 36 and 44 inches; knee space per diner by counter height; cooktop landing area 12 and 15 inches and 9 inches behind an island cooktop; ducted ventilation; recommendations, not code
- Tennessee Residential Code 2018 (IRC 2018), Chapter 24 Fuel Gas, Section G2447.5, on UpCodes — 30-inch vertical clearance above a cooking top to combustible material and metal cabinets; 24 inches with millboard and sheet metal, a metal hood or a listed appliance above
- Nashville and Davidson County Residential Code 2024 (IRC 2024), Chapter 24 Fuel Gas, Section G2447.5, on UpCodes — Same G2447.5 text in Metro Nashville’s 2024 code
- Metro Nashville Codes, Metro adopts 2024 International Building Codes — BL2025-898 signed July 16, 2025, applying to plans and applications submitted after that date
FAQ
Planning a Kitchen Island That Fits the Room — questions
How much clearance do you need around a kitchen island?
The National Kitchen and Bath Association recommends at least 42 inches between the island and facing counters for one cook and 48 inches where two people cook. A side used only as a walkway should be at least 36 inches. These are planning recommendations rather than code, so measure from counter fronts, not cabinet boxes.
How much overhang does an island need for seating?
The NKBA ties knee space to counter height: 15 inches deep per diner at a standard 36-inch counter, 12 inches at a 42-inch bar height and 18 inches at a 30-inch table height, each 24 inches wide. The overhang and the cabinet below together should leave at least that much clear room for knees.
How much counter does an island cooktop need?
Plan 12 inches of counter on one side and 15 on the other, and at least 9 inches of counter behind the burners when the cooktop sits at counter height, as the NKBA recommends. For a gas cooktop, the residential code keeps combustible material at least 30 inches above the cooking top unless it is protected.
How far should an island be from the stove?
Treat the space between them as a work aisle. The NKBA recommends at least 42 inches from the front of the range to the island for one cook and at least 48 inches for two, measured from the counter or appliance front. Less than that and an open oven door or a second cook blocks the way.
How wide should a walkway be in a kitchen?
At least 36 inches, according to the NKBA kitchen planning guidelines. Where two walkways meet at a right angle, one of them should be at least 42 inches wide. A walkway is a path with no work along it; an aisle where someone cooks or cleans up needs 42 inches or more.