How to Cut Porcelain Tile: A Homeowner's Guide

­You should start by learning everything you can about the porcelain you plan to use. Is your ceramic tile glazed or unglazed? There are different degrees of hardness — and different break strengths — to take into consideration. The more you know about your tile, the better you can choose the right tools to cut it.

Here's one idea to abandon right away: cutting porcelain tile the way you would cut anything else. Your standard rotor tool won't do it. You might be able to use a jigsaw, but you'll burn through a few blades. The good news is that one well-chosen tile cutter could last you for the remainder of all your home improvement projects, ever.

Let's start with the tools. A wet saw is the industry standard for cutting tile. The manual tile cutter has a diamond blade so, as you can imagine, it's pretty hard. There are a few tradeoffs: Wet saws aren't cheap, they can be slow, and you can't put adhesive on the tile until it has dried. As a bonus, however, you will be able to use it to cut granite, should your future home improvement projects involve that.

A wet saw does use water, as its name implies; there's a shallow well of water beneath the blade, and the bottom edge of the blade passes through the water as it rotates. That keeps the blade cool and reduces the amount of dust your cutting project kicks up. Its blade is a stationary rotor, something like the blade of a table saw. You simply guide the tile toward the blade. If you don't want to invest in a wet saw, you can always rent one.

Most score-and-snap tile cutters follow the same basic principle: You fit the tile into a cutting bed (sometimes with guides that help keep your cut straight), and then push or pull a rotating blade across the tile's glaze, to score it. After scoring the tile, you break it with a gentle tap. The tile bed is padded to help the tile break evenly and to ensure the tile doesn't move while you score it.

Some cutters have a lever that helps you get consistent, even pressure for the break. With other cutters, you're on your own. You might be able to use a jigsaw with a carbide-grit blade, but keep in mind that porcelain is really strong stuff. If you use a jigsaw, you'll probably have to replace the blade several times in the course of the project.

You'll also need:

Finally, if you're using the wet saw to make diagonal cuts (and if you want to make diagonal cuts, you should be using a wet saw), you'll need a triangular attachment for the saw.

Alternatively, you can use a tile nipper, which is a hand tool used for making irregular cuts or for cutting small notches in porcelain tiles. This tool is particularly useful when you need to cut a tile to fit around irregular shapes, such as pipes or corners that can't be accommodated with straight cuts made by a tile cutter.

If this is your first time, you might want to be on the safe side: Buy a little more tile than you think you'll need. (If you don't wind up using it, you can frame the extra tiles with wood and turn them into coasters or trivets that match the decor.)

First, let's look at the best method of score-and-snap tile cutting, which is the easiest and fastest way to handle straight cuts. Mark the cut on the tile, of course. Then place it in the cutter, and — depending on the model — push or pull the diamond blade over the tile.

People run into problems with tile cutters when the cuts become erratic, leading to uneven edges and chipped tile. You can prevent this in a few ways. First, checking the alignment of the cutter periodically can help you avoid chipping.

Second, use a paintbrush to run a line of light oil along your planned cut, as that will help the blade score the tile smoothly [source: Byrne]. Just remember that the oil can keep your adhesive from sticking, so wipe off all the tiles before setting them.

Making L-Cuts or Diagonals With a Manual Tile Cutter

To make L-cuts or diagonals, you'll need to use a wet saw. Mark the planned cut on the tile carefully with a ruler and a grease pencil. The saw has a guide called a rip fence, which helps you measure and straighten your cut. See the scales at each end? Use them to help you align the tile.

Now that you've aligned the tile with the rip fence, turn on the saw. Guide the tile gently and carefully toward the blade. Don't push hard, and don't keep moving the tile once the blade has cleared it. After you've made the cut, turn off the saw and take the tile out.

Take a look at the cut you've made. Is it clean? Great. If there are chips, you can smooth the cut out with a second pass from the saw.

Dealing With Scorch Marks on Porcelain Tile

One DIY expert notes that you may see some light scorch marks on the cut edge of the tile. (Even a wet saw creates a lot of friction when it passes through porcelain.) Fortunately, grout usually covers that sort of scar [source: Staggs].

As you might imagine, if a blade can leave burn marks even when it's passing through a cooling pan of water, it's traveling pretty fast, and that can be dangerous. Don't even think of starting your project before you've read the next page, where we look at safety tips for cutting porcelain.

Any blade that can cut porcelain has the potential to cut you. Don't ever give a tile-cutting project less than your full attention.

With rotor tools, a rapidly spinning blade bites into whatever you're cutting. It doesn't just slice, it tears. That's what creates the cloud of dust and particles around the tool. You must protect your eyes with safety glasses every time you use a rotor tool. If you don't think it's a problem, imagine getting something in your eye and then having to grope around blindly to shut off a very sharp electronic blade.

The cutting wheel creates a lot of friction when it cuts, and that friction produces heat. Be careful handling and changing blades. You might want to keep a pair of heavy gloves handy to prevent nicks and burns.

One hazard of renting a wet saw is the unfamiliarity of the tool. You don't want to be hesitant or uncertain when you're dealing with a big rotor tool. For one thing, uncertainty can show in the cuts of the final project. Furthermore, if a problem occurs, you want to know immediately how to shut off the saw. Take the time to get to know your rental.

You don't need to engage in a trial by fire, so don't practice on your expensive, custom-matched tiles. Ask your tile supplier if they have a few remnants, discontinued tiles, or other pieces you can practice on. Additionally, you may need to make adjustments in the way you're cutting, moving the guides on the wet saw. Unplug the saw before you do that.

Properly cut and installed, porcelain tile is a lasting investment in the beauty, functionality, and value of your home. Cutting it may be a challenge, but it's one worth attempting.

This article was updated in conjunction with AI technology, then fact-checked and edited by a HowStuffWorks editor.