How to Grout the Edges of a Tile Backsplash

Grouting the edges of a tile backsplash is an important finishing step that helps prevent moisture damage, adhesion issues, and gives your backsplash a polished, professional look. With some preparation and the right techniques, grouting the edges can be a satisfying DIY project. Here is a comprehensive guide on how to grout the edges of a tile backsplash.

Preparing to Grout the Edges

Before you can grout, you need to make sure the tile edges are ready. Here are some tips for prep:

  • Allow tile adhesive to fully cure – Give the tile adhesive 24-48 hours to fully set before grouting. Grouting too soon can cause tiles to shift.
  • Clean the tiles – Use a damp sponge to remove any dirt, dust, or residue from laying the tiles. Grout won’t adhere to dirty tiles.
  • Remove spacers – Carefully pop out any plastic tile spacers you used during installation. This exposes the edges to be grouted.
  • Check for gaps or uneven tiles – Look for any visibly uneven tiles or large grout joints. Adjust tiles if needed so joints are even.
  • Have all materials ready – Gather grout, grout float, grout sponge, bucket for mixing, water, rags, and sealer (if using).

Choosing the Right Grout

For grouting tile edges, unsanded grout is best. Here’s how to choose:

  • Use unsanded grout for joints 1/8 inch or less – Sanded grout can scratch narrow grout joints. Unsanded is smoother.
  • Match grout color to your tile – Choose a grout close to your tile color for a subtle finished look. Use contrasting grout if you want the joints to stand out.
  • Get a polymer-modified grout – This contains polymers that make it more flexible, durable, and water-resistant. Ideal for edges.
  • Consider epoxy grout for heavy use areas – Extremely durable and stain resistant but more difficult to work with. Good for behind ranges.

Always check the manufacturer’s recommendations and test a small area first.

Mixing the Grout

Mixing the grout to the right consistency is key for good adhesion and workability:

  • Follow package directions – Different brands may have slightly different mixing ratios. Don’t overwater the mix.
  • Only mix what you can use in 30 minutes – Grout will start to set, making it unusable. Mix small batches to start.
  • Use a paddle mixer – Hand mixing can leave lumps. Use a drill mixer for smooth, lump-free grout.
  • Aim for a thick, peanut butter consistency – Grout shouldn’t be too runny or sticky. Adjust water to get the ideal texture.
  • Let it slake for 5-10 minutes – Let mixed grout sit so polymers can expand. This improves spreadability.

Applying the Grout

When grouting edges, work in small sections for best results:

  • Apply grout at a 45° angle – Hold the float at an angle and work it diagonally across joints to pack in grout.
  • Take care on edges and corners – Make sure to fully pack grout into any tight corners or thin edges.
  • Check for voids – Carefully look for any gaps or pinholes in the grout and pack in more as needed.
  • Keep grout just below the tile edge – Wipe away any excess grout on the tile face with a damp sponge.
  • Clean as you go – Rinse and wring out your sponge frequently to smooth joints and reveal the final color.
  • Don’t spread too far – Work in small sections of 2-3 sq ft so you can easily reach edges to pack grout.

Curing and Sealing the Grout

Proper curing and sealing are important final steps:

  • Allow 24 hours to cure – Resist wiping or cleaning for the first day. This allows grout to set up fully.
  • Mist the grout after 8 hours – Lightly misting helps cure evenly. Don’t oversaturate.
  • Avoid foot traffic for 24 hours – Keep people and pets off the tiles to prevent disrupting grout.
  • Apply grout sealer – Use a penetrating sealer to protect grout from stains. Apply 2-3 thin coats.
  • Seal again annually – Reapply sealer every year or so to maintain stain and water resistance.
  • Check for haze after 1 week – If a whitish haze appears, it can be carefully removed with vinegar or grout haze remover.

Troubleshooting Grout Issues

If you encounter any problems, here are some troubleshooting tips:

Crumbling, cracking, or powdery joints – Indicates the grout wasn’t given proper time to cure. Removing and re-grouting may be required.

Discolored or stained grout – Can sometimes be cleaned with vinegar, hydrogen peroxide, or baking soda paste. If not, re-grouting may be needed.

Grout falling out or pits in joints – Usually caused by improper application and not packing grout fully into the joints. Regrouting may be required.

Efflorescence – Whitish powdery deposits on grout. Generally harmless but can be removed with white vinegar and stiff brush.

Joint too wide – Edges wider than 1/8 inch can have adhesion issues. May need expanding grout or caulk in wide joints.

Grout Edges with Care for Long-Lasting Results

Grouting tile edges takes care, patience, and proper technique. But when done right, it gives your backsplash a clean finished look that protects joints from damage. Follow these tips on choosing grout, mixing, applying, curing, and troubleshooting, and you can expect beautiful, long-lasting results. Take your time on the edges and corners, allow for proper curing, and keep the grout sealed, and your backsplash edges will stay looking great for years to come.

Frequently Asked Questions

What’s the easiest way to grout edges?

Use an angled float or soft sponge brush to work the grout diagonally across joints. This allows you to pack the grout into thin edges and corners. Work in small sections and take your time focusing on the edges.

How long should I wait before sealing grout?

It’s best to wait a full 72 hours after grouting to apply a penetrating sealant. This allows the grout to fully cure so the sealant bonds effectively.

Why is my grout cracking on the edges?

Thin edge joints are prone to cracking if the grout cures too quickly or unevenly. Make sure to mist the edges lightly during curing and don’t wipe or clean for 24 hours. Cracks usually require regrouting.

Can I use caulk instead of grout on edges?

Caulk adheres well but will need to be replaced over time. For long-lasting results, grout is recommended with a flexible polymer-modified formula made for edges.

What’s the minimum joint size for grouting edges?

Most manufacturers recommend 1/8 inch as the minimum for groutable joint widths. Anything smaller may require caulk instead for proper adhesion.


Grouting tile edges takes precision, but the right techniques will reward you with a flawless finish. Prepping the joints, using quality grout, taking care when applying, and proper curing are the keys to success. Follow this comprehensive guide closely on your next backsplash project, and you can expect beautiful, professional-looking results by grouting carefully along the edges. With some patience and know-how, those edges will look sharp for years to come.