What a kitchen takes, counted box by box.

A kitchen is four jobs wearing one word

When somebody says they are redoing the kitchen, they usually mean one picture in their head. The store sees four separate purchases, bought in four different units, on four different aisles, and that mismatch is most of what makes the whole thing feel unknowable.

Here is the twelve by ten kitchen this page opens with, at an eight foot ceiling, taken apart into the four things it actually is. Every figure below is what the calculator at the top of the page prints for those measurements, and you can watch all of them move by typing your own.

• The floor. Twelve by ten is 120 square feet. The Pergo project planner says to add a ten percent waste factor, which makes 132, then divide by the square feet in one carton and round up. At the 20 square feet per carton this page starts you at, that is 6.6, so seven cartons. Seven cartons is 140 square feet arriving to cover 120.
• The walls. Two times twelve plus ten, times eight feet of ceiling, is 352 square feet, less the 40 square feet of doors and windows the page assumes until you tell it otherwise. That leaves 312. Two coats is 624 square feet of paint, and a named manufacturer data sheet puts a gallon between 350 and 400 square feet, so both ends of that range round up to two gallons.
• The backsplash. Tile is sold by the box and the box is not standardised. Read the number off the carton and type it in.
• The sheets underneath. Walls plus ceiling is 432 square feet. With ten percent for cuts that is 475, and a four by eight panel is 32 square feet, so fifteen sheets. USG packs two panels to a bundle, so fifteen means eight bundles and one spare sheet, which is not a mistake and is worth keeping flat.

The backsplash is not the floor, and the calculator starts out assuming it is

This is the one thing worth reading twice on this page. When you land here, the tile calculator is filled in with your floor footprint, because that is the measurement the room gave it. A backsplash is a completely different rectangle. It is the run of counter multiplied by the height from the counter to the underside of the cabinets, and in most kitchens that height is somewhere near eighteen inches.

So switch to Tile on the strip and type the real thing: the length of the run in the length field, and the height as a decimal in the width field. Eighteen inches is 1.5. Twelve feet of counter at 1.5 is 18 square feet, and that is a different order of magnitude from the 120 the floor asked for. Doing this correctly is worth more than every other refinement on this page, because tile is the item where over ordering hurts most.

The thin-set line moves with it. CUSTOM Building Products publishes 85 to 95 square feet per 50 pound bag with a quarter inch square notch trowel, and 60 to 67 with a quarter by three eighths. That is not a rounding difference. Choosing a bigger trowel, which larger format tile often requires, can change your bag count more than changing the room does.

The order the work happens in, and the order the money leaves

Kitchens go wrong in sequencing more than in arithmetic. Drywall and any patching comes first, because everything after it is either painted or stuck to it. Priming and the first coat of paint go on before the backsplash, since cutting a clean line against finished tile is a skill and cutting against bare wall is not. The floor usually goes in before the base cabinets if it is running wall to wall, and after them if it is not, and that single decision changes your square footage by whatever the cabinet footprint is. The backsplash goes last, because it is the only part anybody photographs.

The money leaves in a different order than the work. The sheets and the mortar and the underlayment are cheap and get bought in one trip. The floor and the tile are the two numbers that decide the project, and both of them are priced per box in a way that makes comparing two stores harder than it looks. Convert everything to the carton or the box before comparing anything, because that is the smallest unit you are allowed to buy.

What this page does not know about your kitchen

It does not know that the wall behind the range is not square, that there is a soffit above the cabinets, or that the previous owner tiled straight onto something the mortar data sheet says not to tile onto. It does not know your cabinet layout, so the floor number treats the room as an empty rectangle, which is the right assumption if the floor runs under the cabinets and a generous one if it does not. And it knows nothing about plumbing, electrical or what happens when the range moves eighteen inches to the left, which is the single most expensive sentence in any kitchen conversation.

It gives you the material shape of the job, sourced and shown open, so that the conversation about everything else starts from somewhere real.