How Much Grout for Backsplash: A Complete Guide

Introduction

Installing a backsplash is a great way to add visual interest and protect the walls behind sinks, stoves, and countertops from water damage and stains. When installing a backsplash, one of the key steps is properly grouting between the backsplash tiles. Knowing how much grout to purchase and apply for your backsplash project is important for achieving full grout coverage without having a lot of wasted, unused grout after the job is complete.

In this complete guide, we will cover everything you need to know about how much grout for backsplash projects, including recommendations for calculating the right amount of grout to buy, tips for proper application and spreading of grout, and the tools and materials needed. With the information in this guide, you’ll be able to determine the right grout coverage and purchase the correct quantity of grout for your unique backsplash installation.

How to Calculate How Much Grout You Need for a Backsplash

To determine the right amount of grout to buy for your backsplash project, you’ll need to calculate the square footage of your backsplash area. Here are the steps:

Measure the Backsplash Area

Measure the length and height of the backsplash area. Include the entire area that will be tiled, even if you plan to leave gaps for outlets or switches.
Multiply the length x height to get the total square footage of the backsplash.

For example, if your backsplash area is 8 feet long and 4 feet high, the total square footage would be:

8 feet x 4 feet = 32 square feet

Account for Gaps Between Tiles

The square footage measurement from the previous step reflects the total area covered by the backsplash tiles and grout combined. However, you’ll need to buy enough grout to fill just the gaps between the tiles themselves.
As a general rule of thumb, tile gaps take up about 25% of the total backsplash area.
To calculate grout coverage needs, multiply the total square footage by 0.25.

Using the example above with a 32 sq ft backsplash area, the grout coverage would be:

32 sq ft x 0.25 = 8 sq ft of grout coverage needed

This 8 sq ft number provides an estimate of how much surface area the grout needs to cover between the tiles.

Determine Grout Amount Based on Coverage

For every 8 sq ft of grout coverage, you’ll need about 1 gallon of grout. This rule applies to standard grout joint widths of 1/8 inch.
Divide your total grout coverage square footage by 8 to get the number of gallons of grout needed. Round up to the nearest whole gallon.

With 8 sq ft of coverage in the example backsplash:

8 sq ft coverage / 8 sq ft per gallon = 1 gallon of grout needed

So for a 32 sq ft backsplash area with 25% taken up by 1/8 inch grout lines, 1 gallon of grout would be required.

This calculation method provides a good starting point for determining how many gallons of grout to purchase. Having a little extra grout on hand can be useful in case of spills, mistakes, or wider grout lines.

Tips for Spreading Grout on Backsplashes

Once you’ve purchased the right amount of grout for your project, proper application and spreading of the grout is essential for maximizing coverage and avoiding problems. Here are some useful tips:

Only apply grout to a few square feet at a time so it doesn’t dry out before you can spread and clean it up properly.
Use a rubber grout float or squeegee to spread the grout evenly and pack it tightly into the joints, holding the float at a 45° angle.
Spread grout diagonally across the tiles first and then spread it vertically and horizontally for the best coverage.
Remove excess grout with minimal pressure to avoid pulling grout back out of the joints.
Immediately clean grout haze from the tile surface with a damp sponge in circular motions. Rinse and re-dampen sponge frequently.
Don’t let cleaned areas dry out before giving them a final wipe with a soft, dry cloth.
Don’t spread more grout than you can clean up within the manufacturer’s recommended time, often 10-30 minutes.

Following these tips will help you fully fill the tile joints while keeping the actual tile faces clean for an optimal grouted backsplash.

Grout Amount Factors to Consider

While the 1 gallon per 8 sq ft of coverage is a good general rule for 1/8 inch grout lines, a few factors can alter how much grout is actually needed:

Tile size: Smaller backsplash tiles with more grout joint area will require more grout per sq ft than larger tiles. Mosaics can need up to 50% more grout than the standard 1:8 ratio.
Grout line width: Standard 1/8 inch lines require less grout than wider 3/16 or 1/4 inch grout lines. Wider grout lines need up to 30% more grout per sq ft.
Grout texture: Smoother, finer grout takes more product to fill joints than coarser, thicker grouts. Deeply textured grouts can reduce the amount needed by 15-20%.
Tile material: Natural stone and irregular tiles need more grout to account for wider joints and uneven edges. The 1:8 ratio is best suited for uniform ceramic or glass tiles.
Grout product waste: Some residual grout will be left in buckets and tools, so the actual amount purchased should exceed the perfect-spread calculation a bit.

Adjust your grout quantity estimate up or down based on these factors to determine the optimal amount to purchase.

Recommended Grout Types for Backsplashes

For backsplash installations, epoxy and cement-based grouts are better options than latex grout:

Epoxy grout: Extremely durable and stain-resistant, great for protecting the grout lines in cooking zone backsplashes. Needs careful application to avoid cracking.
Cement grout: The most common type, provides good durability at an affordable price. Unsanded grout is best for backsplash joints under 1/8 inch.
Latex grout: Not ideal for backsplashes since additives make it less heat and stain resistant. Better suited for floor tile grout.

Make sure to choose a grout color that complements your backsplash tiles. Contrasting or matching the grout color to the tiles can dramatically change the look.

Tools and Materials Needed

In addition to the grout itself, you’ll need the following tools and supplies:

Grout float or rubber grout spreader
Grout sealing sponge
Clean buckets of water
Soft, clean cloths
Tile cleaning solution
Grout sealer (recommended)
Masking tape (if needed)
Caulk for corner gaps (if needed)

Proper materials like sponges designed specifically for grouting will make the process much easier. Having everything ready beforehand ensures you can spread and clean the grout efficiently.

Step-by-Step Grout Application Process

Once you have the right amount of grout and necessary tools on hand, follow these steps for flawless grout application:

Clean and dry the tile surface thoroughly first.
Apply masking tape around the perimeter if needed to keep surrounding areas clean.
Mix the grout as directed on the packaging and let it slake for the recommended time.
Use a rubber grout float or squeegee to spread grout diagonally across a small working area.
Pack the grout tightly into the joints by holding the float at a 45° angle.
Wipe diagonally again then spread the grout horizontally and vertically.
Let the grout firm up slightly but not dry completely.
Holding the sponge at a 90° angle, gently wipe diagonally to remove excess grout without pulling it out of the joints.
Rinse and wring sponge until water runs clear. Dampen sponge again as needed.
Wipe entire area with clean, dry cloths to remove haze once main excess grout is cleaned up.
Repeat steps 3-10 for the next small working section until the entire backsplash is grouted.
Avoid overlapping wet and dry edges.
After the final wipe with dry cloths, allow grout to cure fully before sealing or using the backsplash.

Careful adherence to this process will help ensure you get maximum grout coverage from the amount you purchased without any shortage. Taking it step-by-step prevents the grout from drying too quickly.

Common Grout Coverage Issues and Solutions

Despite the best preparations, you may still run into some problems with fully covering the joints or having grout cracks develop:

Problem: Grout coverage appears short, joints not completely filled.
Solution: Ensure you are packing the grout tightly into the gaps and letting it firm up slightly before wiping. Larger gaps may need two passes of grouting.

Problem: Grout dried too quickly and could not be cleaned off tiles.
Solution: Only grout in small, manageable sections. Immediately wipe away excess grout with damp sponge before it dries.

Problem: Grout cracking or crumbling after curing.
Solution: Make sure to follow manufacturer mixing instructions. Avoid excess water which can weaken grout. Ensure grout joints are an even depth.

Problem: Grout haze won’t come off tiles.
Solution: Wipe the tiles down with tile cleaning solution or vinegar. Use a buffing pad or very fine sandpaper if needed.

Paying close attention to the working time of the specific grout product and maintaining properly dampened sponges helps avoid many of these problems.

How Much Grout for Backsplash: Final Tips

Carefully store any leftover grout since it can typically be re-used for future repairs or grouting jobs.
Don’t skimp on grout lines in the pursuit of less grout usage. Proper joint spacing is essential for preventing cracks and allowing movement.
Avoid wiping joints too deep since that can compromise grout adhesion and durability over time.
Consider sealing cement grout after curing for added stain protection, especially for cooking zone backsplashes.
Change rinse water buckets frequently to prevent spreading dirty grout water onto clean tiles.

Determining and applying the right amount of grout for your specific backsplash project takes some careful planning and preparation. Following the recommendations in this guide will set you up for backsplash grouting success. Let us know if you have any other grout quantity or application tips!

Frequently Asked Questions About How Much Grout for Backsplash

Grouting a backsplash can seem intimidating for first-time tilers. Here are answers to some common FAQs about calculating and working with the right amount of grout for backsplash installations.

How much grout coverage is needed per square foot?

The typical amount of grout coverage needed is around 1/4 of the total square footage, assuming 1/8 inch grout lines and standard tile sizes. This accounts for gaps between tiles taking up about 25% of the backsplash area.

Can I use latex grout for a backsplash?

Latex grout is not ideal for backsplashes since additives make it less heat and stain resistant. Cement or epoxy grout provide better durability.

How much grout do small backsplash tiles need?

Smaller tiles with more grout joint area relative to the tile size will need around 20-50% more grout per square foot than the standard 1 gallon per 8 square feet estimate.

What is the easiest way to calculate needed grout?

Measuring the square footage and multiplying by 0.25 provides a good starting estimate. Adjust up or down based on your tile size, grout line width, and grout texture.

Should I mix all the grout at once or do small batches?

Only mix up enough grout for what you can apply and clean within the manufacturer’s specified time, often 10-30 minutes. Mixing it all at once can lead to drying and wasted grout.

How soon can I seal or use my backsplash after grouting?

It’s important to allow cement grout to cure fully first, usually 24-72 hours. Epoxy grouts cure more quickly but sealing is still recommended after 24 hours minimum.

How do I calculate grout needs for unusual shaped backsplashes?

For uniquely shaped areas, sketch the layout and divide into rectangular sections to get separate measurements of height x width. Then add together for total area and grout needs.

What’s the easiest technique for spreading grout evenly?

Use a rubber grout float in a diagonal direction first, then spread horizontally and vertically without removing too much grout. Let it firm up slightly before cleaning.

Why is my grout cracking after it cured?

Cracking can be caused by inadequate mixing, uneven joint depths, rapid drying, or joints wider than the grout was designed for. Using grout release agents can also prevent proper bonding and lead to cracks.

Conclusion

Determining the right amount of grout for a backsplash is an important first step in any grouting project. With some simple measurements of the backsplash area and tile joint gaps, you can calculate the approximate grout coverage needed. Being prepared with the right tools and materials, taking precautions against rapid drying, and properly packing and cleaning the grout will help ensure you get maximum coverage from your grout quantity. Consider the tips in this guide when planning your next backsplash grouting task. What grouting tricks have worked for your backsplash projects? Let us know in the comments!