Installing a beautiful new backsplash in your kitchen or bathroom can completely transform the look and feel of the space. However, ensuring proper installation is key to achieving a high-quality, long-lasting backsplash. One of the most important tools for proper backsplash installation is the v notch trowel. But what size v notch trowel is best for installing backsplash tile?
What is a V Notch Trowel?
A v notch trowel is a specialty trowel used to apply tile mortar or thinset when installing tile. The notches in the trowel create ridges in the mortar which allow the tile to be embedded to the proper depth. This provides maximum mortar contact and adhesion to the tile backing material.
V notch trowels come in a variety of sizes, from 3/16″ to 1/2″ notches. The size of the notches determines how much mortar is applied to the surface and how thick the mortar bed will be under the tile. Using the proper sized v notch trowel is imperative to achieving proper mortar coverage and tile installation.
Key features of a v notch trowel:
- Metal blade with v-shaped notches
- Notches create ridges in applied mortar
- Allows mortar to be embedded under tiles
- Available in different notch sizes
- Essential for proper tile installation
Choosing the Right V Notch Trowel Size
So how do you determine the correct v notch trowel size for your backsplash installation? Here are the key factors to consider:
Backsplash Tile Type and Size
The size and type of your backsplash tile is the first consideration. Smaller tile sizes like mosaics, penny tiles, and tiles under 4 inches generally require a smaller v notch trowel such as 1/4″ or 3/16″. Medium tiles in the 4-6 inch range often use 1/4″ or 3/8″ trowels. For larger tiles over 8 inches, a 1/2″ trowel is commonly recommended.
Stone and glass backsplash tiles that have irregular thicknesses may need a deeper notch trowel to account for the variances. Consult the tile manufacturer’s recommendations to determine the best trowel size.
Trowel Suggestions Based on Tile Size:
- Mosaics/tiles under 2″ – 3/16″ v notch
- Tiles 2″- 4″ – 1/4″ v notch
- Tiles 4″-6″ – 1/4″ or 3/8″ v notch
- Tiles 6″-8″ – 3/8″ v notch
- Tiles over 8″ – 1/2″ v notch
Mortar Type
The type of mortar product you are using is another important factor. Latex-modified thinset mortars and medium bed mortars typically require a trowel with larger notches to properly gauge the thickness. Standard thinset mortars can often use smaller notch trowels.
Consult manufacturer specifications to see their recommended trowel size for the mortar type and tile application. This will help ensure you achieve the proper mortar bed thickness.
Trowel Size Guidelines Based on Mortar Type:
- Standard thinset – 3/16″ to 3/8″ notch
- Medium bed mortar – 1/2″ to 3/4″ notch
- Latex-modified thinset – 3/8″ to 1/2″ notch
- Large/heavy tile mortar – 1/2″ to 3/4″ notch
Tile Backing Material
The substrate material you are tiling onto is also a key factor in choosing your v notch trowel. Rough, uneven surfaces like concrete, cement board, or existing tile require larger notches to allow the mortar to fill any voids behind the tile. Smoother backing materials like plaster or drywall often require less mortar thickness, allowing the use of smaller notch trowels.
Trowel Size Guidelines Based on Substrate Material:
- Concrete/masonry – 1/2″ to 3/4″ notch
- Cement backerboard – 1/4″ to 1/2″ notch
- Existing tile – 3/8″ to 1/2″ notch
- Drywall – 3/16″ to 1/4″ notch
- Plaster – 3/16″ notch
Surface Flatness
The flatness or evenness of the surface you are tiling onto should also factor into choosing a trowel size. Surfaces with significant warping, gaps, or inconsistencies will require a thicker mortar bed achieved with a larger notch trowel. Extremely wavy or uneven surfaces may benefit from a skim coat to flatten them out prior to using a v notch trowel.
Trowel Size Based on Surface Flatness:
- Highly uneven surface – 1/2″ to 3/4″ notch
- Moderately uneven surface – 3/8″ to 1/2″ notch
- Slightly uneven surface – 1/4″ notch
- Flat, even surface – 3/16″ notch
Best Practices for V Notch Trowel Use
Once you’ve selected the appropriate v notch trowel size, proper technique is crucial for successful thinset application. Follow these best practices when using a v notch trowel:
- Hold the trowel at a 45° angle to the surface when applying mortar.
- Apply even pressure when spreading mortar to ensure consistent depth.
- Use the flat side of the trowel to initially “knock down” high spots.
- Twist the trowel slightly when applying mortar to create ridges.
- Maintain ridges while placing tile by applying mortar only in small sections.
- Embed tiles with a slight twisting motion for maximum mortar contact.
- Periodically check mortar ridges to ensure proper coverage is maintained.
- Discard and replace mortar once drying or skinning begins.
Proper v notch trowel technique helps maximize mortar transfer and coverage under tiles for a durable, long-lasting installation.
What Size V Notch Trowel for Common Backsplash Situations
Here are some more specific recommendations for v notch trowel sizes in typical backsplash tiling applications:
Glass Tile Backsplash on Drywall
For a glass mosaic tile backsplash being installed onto drywall, a 1/4″ v notch trowel is ideal. The small mosaic tiles paired with the smooth drywall surface make a thinner mortar bed sufficient. The 1/4″ trowel notch will allow proper embedding of the small tile sizes.
Ceramic Tile Backsplash on Cement Board
A 3/8″ v notch trowel is a good choice for a standard ceramic or porcelain tile backsplash being installed on cement backerboard. The coarser texture of the cement board requires a slightly thicker mortar bed. The 3/8″ notch will accommodate the common 4-6 inch ceramic tile sizes.
Large Format Tile on Existing Backsplash
To install large format 12″ x 24″ ceramic tiles over an existing backsplash, use a 1/2″ v notch trowel. The larger tile size and uneven surface of the existing tile requires more mortar. The 1/2″ notch will allow large tiles to be fully embedded.
Stone Tile on Concrete Surface
For a stone tile like travertine or marble on a concrete surface, a 3/4″ v notch trowel is best. The natural irregularities of stone tiles paired with the variability of a concrete substrate needs a thicker mortar bed. Use latex-modified thinset for natural stone.
Subway Tile on Plaster Wall
On a flat plaster wall, 3/16″ v notch trowel is suitable for classic 3″ x 6″ subway tiles. The small grout lines of subway tile allows a thinner mortar bed on plaster’s smooth surface. Be sure to skim coat any uneven areas first.
V Notch Trowel Size Recommendations
As a quick reference, here are the recommended v notch trowel sizes for common backsplash applications:
|Tile Type|Tile Size|Backing Material|Recommended Trowel Size|
|-|-|-|-|
|Mosaic glass|1″ x 1″|Drywall|1/4″ v notch|
|Ceramic|4″ x 4″|Cement board|3/8″ v notch|
|Porcelain|6″ x 6″|Concrete|1/2″ v notch|
|Marble|12″ x 24″|Existing backsplash|1/2″ v notch|
|Travertine|12″ x 12″|Plaster|3/8″ v notch|
|Subway tile|3″ x 6″|Greenboard drywall|3/16″ v notch|
Achieving Full Mortar Coverage
While the v notch trowel size determines the thickness of the applied mortar, proper technique is still crucial to achieve full adhesive coverage under each tile. After embedding tiles, periodically remove a tile and inspect the back to ensure the tile backing is at least 80-95% covered in mortar.
Targeting 80-90% mortar coverage is recommended by most tile authorities. Voids or gaps in coverage can lead to cracks, loose tiles, and other bond issues. Paying close attention to coverage and consistency of mortar application will ensure your backsplash looks beautiful and lasts for years to come.
Tips for Gauging Proper Coverage
Here are some helpful tips for gauging whether you are achieving proper thinset coverage as you install your backsplash:
- Focus on consistent technique – don’t speed up or slow down trowel application.
- Occasionally remove and check coverage on a tile or two.
- Target 80-90% coverage – small voids are OK but no large gaps.
- Adjust trowel angle or pressure if coverage is too little or too much.
- Use the flat trowel side to flatten any high ridges or globs.
- Discard thinset once drying begins – don’t add water to reconstitute.
- Change trowel size if needed – go up or down a size.
- Take your time – don’t rush the mortar application steps.
Achieving Full Contact and Adhesion
In addition to proper mortar coverage, it is critical to achieve full contact between the tile and substrate surface. Use a slight twisting motion when embedding tiles to flatten ridges and eliminate voids or air gaps. Avoid “tile shifters” which can break the adhesive bond later.
Check coverage and make any needed technique adjustments periodically as you install. This will help ensure you achieve maximum mortar-to-tile contact and a long-lasting bond. Proper thinset application takes practice – don’t hesitate to remove and re-apply tiles until comfortable.
V Notch Trowel Size FAQs
Q: What happens if I use the wrong size v notch trowel?
Using too large of a trowel notch can result in too much mortar and difficulty embedding tiles. Too small of a notch provides insufficient coverage. Both situations can lead to failed adhesion, cracked grout, or loose tiles over time.
Q: Can I use a standard trowel instead of a v notch for backsplash?
V notch trowels are specially designed to gauge the proper mortar thickness for tile. Standard trowels do not meter mortar correctly. Always use a v notch trowel for tile application.
Q: How do I clean dried thinset off a used v notch trowel?
Gently knock off dried material, then soak the trowel in warm water for 5-10 minutes. Use a brush and sponge to scrub off remaining debris. Avoid using harsh chemicals that can damage the trowel.
Q: Can I use a v notch trowel on the walls for backsplash?
Yes, v notch trowels can be used to apply mortar on both horizontal and vertical surfaces. Apply in small sections working top to bottom and maintain ridges by embedding tiles promptly.
Q: What if my substrate varies – do I need two trowel sizes?
It’s best to use one consistent trowel size based on the most uneven section. Using two sizes risks thickness inconsistencies. Level any high spots first for an even mortar bed.
Conclusion
Choosing and using the proper v notch trowel size is imperative for successful backsplash installation. Consider tile type, mortar, substrate, and surface evenness when selecting a trowel. Target 80-90% mortar coverage under tiles and use proper technique. Ask tile retailers for product-specific trowel recommendations. Investing in the right tools and methods will deliver beautiful, long-lasting results!