How to Install a Subway Tile Backsplash


Installing a subway tile backsplash can transform the look of your kitchen or bathroom. The classic rectangular shape and clean lines of subway tiles create a timeless and elegant backdrop. Subway tiles are also an easy weekend DIY project for most homeowners. With some planning and preparation, you can have a beautiful new backsplash in just a couple days.

In this comprehensive guide, we will walk through all the steps for how to install a subway tile backsplash successfully. We will cover how to prepare your work surface, select quality tile and grout, use spacers for consistent spacing, cut tiles to fit, apply thinset mortar evenly, install tiles in the right pattern, grout the joints, and finally seal and protect your finished backsplash.

Whether you’re tiling a small area behind a stove or an entire wall from counter to ceiling, these tips will ensure your subway tile backsplash looks fantastic. So let’s get started!

How to Prepare the Surface

Before beginning your subway tile installation, proper preparation of the surface is crucial. Take time to prep your surface to ensure the tiles adhere well and last.

Clean and Sand the Area

  • Thoroughly clean the installation area with soap and water to remove grease, dust and debris.
  • Allow the surface to fully dry.
  • For existing drywall, lightly sand to scarify the surface and remove any gloss or paint. This helps the thinset mortar adhere better.
  • For water-resistant drywall, score the surface with a utility knife before sanding. This allows the thinset to grip better.
  • Sand existing tile or backsplashes to roughen the surface before tiling over.

Remove Outlets and Switch Plates

Use a screwdriver to temporarily remove any outlets, switch plates, or fixtures from the installation area. You’ll likely need to cut tiles to fit around these items. Removing them ahead of time gives easier access.

Fill Any Holes or Imperfections

Examine the surface and use spackle or drywall joint compound to fill any holes, cracks, or imperfections larger than 1/8 inch. Allow filler to dry completely according to manufacturer instructions.

Prime Painted Surfaces

If tiling over previously painted drywall or other surfaces, apply a coat of primer to prevent the thinset from reacting with the paint. Allow primer to dry fully before tiling.

Proper prep leads to better adhesion and a longer lasting finish. Now your surface is ready for tiling!

Selecting Your Subway Tiles and Grout

Once your surface prep is complete, the next step is gathering supplies. Choosing high quality subway tiles and grout will ensure an attractive, durable outcome.

Subway Tile Options

  • Glazed ceramic – budget friendly, shiny finish
  • Porcelain – less porous than ceramic, matte or glossy finish
  • Glass – transparent or colored, glossy finish
  • Mosaic mesh sheets – self spacing small tiles on mesh backing
  • Natural stone – marble, travertine, granite – higher cost

Consider your design, budget, and the amount of use the area will get when choosing tile. Check tile edges to ensure they are cut straight and consistent in size.

Grout Options

  • Sanded – best for joints 1/8 inch and larger
  • Unsanded – for floor joints under 1/8 inch and wall joints
  • Epoxy – long lasting, moisture resistant, needs sealing
  • Silicone – flexible, water resistant, stain resistant

Choose grout color and texture to complement your tile size and pattern. Contrasting grout can accent each tile, matching grout creates a unified look.

Calculate How Much You Need

Measure the area to tile and add 10% extra to account for tile cuts and waste. Order slightly more tile and grout than needed so you don’t run short.

Using Tile Spacers for Consistent Grout Lines

Tile spacers are small plastic crosses that allow you to space subway tiles evenly apart. Spacers create uniform grout line width for a clean finished look.

  • Spacers are available in different sizes for various grout line widths, typically 1/16″, 1/8″, or 3/16″.
  • Choose a width based on your tile size – smaller tiles suit thinner grout lines.
  • Use spacers on every tile edge to keep all grout lines parallel and even.
  • Place spacers as each tile is set before applying next tile.
  • Remove spacers after grouting; spacers are reusable.

Properly spacing all your tiles with spacers is the secret to flawless grout lines!

How to Cut Subway Tiles

Most tile backsplash installations will require some subway tile cutting to fit around outlets, pipes, corners, or edges. Cutting tile may seem daunting, but with the right tools it’s not difficult.

Tools for Cutting Tile

  • Carbide-tipped score and snap cutter – simple and inexpensive
  • Tile nippers – nibble small pieces after scoring
  • Wet saw – electric for accurate straight cuts and mitered edges
  • Angle grinder – for L-shaped and U-shaped cuts

Measure Precisely

Measure the area needing custom cut tile and transfer dimensions to the tile. Double check measurements for accuracy.

Score and Snap

Use the score and snap cutter to score the tile on the marked line. Scored side facing up, snap the tile downward over an edge.

Nip Small Pieces

For small irregular cuts, lightly tap tile nippers along the scored line to nibble off small pieces.

Use a Wet Saw for Precise Cuts

For outlets, pipes, and edge pieces, a wet saw fitted with a diamond tile blade provides clean straight cuts. Mark the line and run the tile through the saw along the cutting guide.

With the right tools and careful measurement, cutting subway tile is easy. Practice first on scrap tiles if needed to get the hang of it.

Applying Thinset Mortar

Thinset is the mortar adhesive used to apply tiles to surfaces. Good thinset coverage and technique ensures a strong bond.

Choose the Right Thinset

  • For walls, use white multipurpose thinset. It cures fast and gains strength rapidly.
  • For floors, use polymer modified thinset. It’s more flexible and has higher adhesion strength.
  • Match thinset to tile material – cement for porous tiles, epoxy for impervious.

Prepare the Thinset

Pour dry thinset powder into a bucket and add the appropriate amount of water or latex additive per manufacturer instructions.

Mix Thinset to Toothpaste Consistency

Mix with a paddle mixer on low speed until homogeneous and smooth, with no lumps. Proper consistency resembles toothpaste.

Apply Thinset with a Notched Trowel

Choose a trowel size to match your tile – 1/4″ x 1/4″ notch for tiles up to 6″x6″, 1/2″ x 1/2″ notch for larger tiles.

Hold the trowel at a 45° angle to the surface and evenly spread a thin layer of thinset over a small area.

Back-Buttering Tiles

After spreading thinset, use the flat side of the trowel to apply a skim coat of thinset to the back of each tile before placing, known as back-buttering. This improves adhesion.

Take care to achieve full thinset coverage between tiles and substrate. Consistent thinset application prevents hollow spots or loose tiles later.

Setting the Tiles in the Proper Pattern

Arranging subway tiles in the right pattern makes the installation look clean and orderly. Planning your pattern ahead ensures proper spacing and alignment.

Offsetting Half Staggered Brick Pattern

The most common and visually appealing pattern for installing subway tile is an offset half staggered brick pattern.

  • Each horizontal row is offset half a tile from the row below in a bricklike layout.
  • Vertical columns align but horizontal rows offset.
  • Avoid lining up vertical grout lines which looks uneven.

Measure and Mark Tile Centres

Map out your pattern and mark horizontal and vertical centre lines on the surface as guides. Measure and mark 16″ vertical columns for standard 3″x6″ subway tile.

Dry Lay a Few Tiles

Start by dry laying a few tiles using spacers before applying thinset. Confirm you have the desired pattern aligned evenly on the centre marks before adhering tiles.

Check Corners and Sides

Visually inspect the first few tiles are plumb and level. Adjust as needed before thinset cures. Use a level and carpenter’s square tool to check corners.

Tile Out From Centre

Work methodically outward from the central vertical line. Keep spacers aligned properly as you progress. If the area is prone to moisture, apply sealant at perimeter tiles.

Taking time to start the pattern correctly and checking alignment ensures straightgrout lines and a uniform finish.

Grouting Subway Tile Joints

Grout fills the joints between tiles, completing your backsplash. Proper grouting technique seals the tiles and prevents moisture issues.

Waiting Period Before Grouting

Allow thinset mortar to cure fully before grouting, typically 24-48 hours. Check manufacturer directions on cure times. Grouting too soon can displace tiles as the thinset continues to dry and shrink.

Mix and Apply Grout

Follow product instructions for mixing grout powder and latex additive to a thick peanut butter consistency. Holding a rubber grout float at a 45° angle, force grout firmly into joints so no gaps remain.

Clean Excess Grout

Allow grout to firm up slightly, then hold grout float edge flat and scrape diagonally across tiles to remove excess grout. Dip float in water bucket frequently.

Final Clean and Polish

Use a damp grout sponge in a circular motion to smooth joints and shape grout edges. Rinse sponge frequently. Remove haze with a soft cloth once dry.

Allow Final Cure

Let grout cure fully 72 hours before exposure to moisture. Avoid heavy cleaning during this period. MANUFACTURER allows final polish and slight haze removal after full cure.

With practice, grouting can produce smooth consistent joints that really make your tile pop!

Sealing and Protecting the Finished Backsplash

The final step is applying a penetrating sealant to protect porous grout lines and enhance the look of your new subway tile backsplash.

Clean Surface Before Sealing

Verify grout is fully cured before sealing. Wash the entire tiled surface with a tile cleaner and rinse thoroughly. Allow to fully dry.

Apply Sealant Liberally

Using a paintbrush or clean cloth, apply a liberal coat of grout sealant over all grouted areas. Avoid contact with tiles themselves as sealant can cause streaks.

Allow Sealant to Penetrate

Let sealer soak in 10-15 minutes. Don’t allow sealer to puddle or dry on the surface. Wipe up any excess with a cloth.

Additional Coats If Needed

For porous grout, apply a second coat of sealant to ensure water repellency. Always follow manufacturer recommended number of coats for the product used.

Cure Time

Allow sealer to cure fully before exposure to water, generally 24-72 hours. Avoid heavy cleaning during this period.

Sealing completes your backsplash tile installation! Proper sealing prevents stains and makes ongoing maintenance easier.

Helpful Tips and Tricks

Here are some additional pointers to ensure your first tile backsplash project goes smoothly from start to finish.

  • Carefully read and follow all manufacturer instructions for thinset mortars, grouts, and sealants selected.
  • Organize tiles and supplies in the room before mixing adhesives to prevent moving wet product through house.
  • Work in small sections so thinset and grout don’t dry out before tiles are applied and cleaned.
  • Make relief cuts when tiling around outlets and switches to prevent cracking tile corners.
  • Use a bucket of water to dip sponges and tools to keep them clean while working.
  • For cut edge tiles on corners and edges, use edge spacers or temporary edge trim for clean straight grout lines.
  • Wipe up thinset, grout, and sealant from tile faces before drying using a damp sponge to prevent streaking.
  • Don’t walk on floor tile until thinset has cured fully, typically 24-48 hours.
  • Apply painter’s tape to walls above backsplash area to prevent thinset and grout splatter.
  • Use a grout sealing product with built in mold and mildew resistant additives.
  • Caulk the joint between countertop and subway tiles with flexible silicone caulk, not grout.

With attention to detail and proper materials, you can achieve stunning results on your first tile backsplash project. Proper preparation, careful tile setting, grouting, and sealing will result in an eye-catching focal point you’ll enjoy for years.

Frequently Asked Questions

What thinset should I use for subway tile?

For walls, use a polymer-modified thinset or one specifically formulated for tile. Avoid multipurpose mastics which dry too quickly. For floors, use a polymer-fortified thinset rated for floor installations.

What size notched trowel do I need?

Use a 1/4″ x 1/4″ square-notch trowel for tiles under 6″ x 6″. For larger tiles, use a 1/2″ x 1/2″ trowel to achieve proper thinset thickness behind each tile.

How long does thinset need to cure before grouting?

Allow 24-48 hours minimum for thinset to cure before grouting tiles. This prevents the grout from loosening the tiles as the thinset continues to dry and shrink. Check manufacturer instructions.

Should spacers be removed before or after grouting?

Spacers should be removed after the tiles are firmly set but before grouting. Removing them ahead of time provides consistent spacing. Leaving them until after grouting makes them hard to extract.

How soon can I expose the tiles to water after grouting?

Allow grout to cure fully 72 hours before exposure to water. Avoid heavy cleaning during this period which can damage grout joints before they cure completely.

How often should I seal my tile backsplash?

Seal grout joints annually to maintain water repellency and stain resistance. For heavy use areas like kitchens, reapply sealer every 6 months. Be sure to clean thoroughly before resealing.


Installing subway tile is an approachable DIY project for most homeowners. Following the techniques outlined here will help you achieve success on your first tiling project. Prepping your surface, using quality thinset, proper tile handling, expertly grouting, and sealing are the keys to a long-lasting, attractive result.

With a trendy yet classic subway tile backsplash, you can add style, brightness, and value to your kitchen or bath. The clean lines and versatile shape of subway tile complement both traditional and contemporary decor.

We hope these step-by-step instructions give you the confidence to tackle tiling your own backsplash. Let us know if you have any other questions as you plan your project!