Installing a beautiful backsplash in your kitchen or bathroom can really upgrade the look and feel of the space. A key tool for proper backsplash installation is the notched trowel, which helps apply tile mortar evenly. But what size notched trowel should you use for your backsplash project? This comprehensive guide will walk you through how to choose the right trowel size.
What is a Notched Trowel?
A notched trowel is a special trowel used to spread tile mortar or thinset when installing tile. The notches create ridges that ensure the tile adhesive adheres properly to the tile backing and allows for even depth and coverage. Notched trowels come in different notch sizes – the notch size impacts how much mortar is applied.
Choosing the right size notched trowel is important to ensure proper coverage and adhesion for the tile. Using the wrong size could result in tiles not sticking properly or too much mortar being used.
Factors That Determine Notched Trowel Size
There are a few key factors that determine which size notched trowel you need for your particular backsplash installation:
Tile Size
The size of the tile you are installing is the most important factor. Larger tiles require a trowel with deeper notches to ensure sufficient mortar coverage. Small mosaics and thin subway tiles require a smaller notch size.
Tile Type
The material the tile is made from also impacts the trowel size. Natural stone tiles require more mortar coverage due to their uneven backs, so a larger notch is needed. Porcelain or ceramic may only need a small notch. Glass tiles need good adhesion so usually require a medium-large notch.
Substrate Type
What you are applying the tile to affects the amount of mortar needed. Drywall requires more mortar than cement board. Existing tile or plaster needs a larger notch than plywood.
Notch Size Guide for Backsplashes
Here is a general guideline on which notch size to use based on tile size:
- Mosaics smaller than 2”x2” – use a 1/4” x 1/4” square notch
- Standard subway tiles, 3”x6” or 4”x4” – use a 1/4” x 3/8” square or U notch
- 6” x 6” tiles – use a 1/2″ x 1/2″ square notch
- Large format tiles 12”x12” or larger – use a 1/2” x 1/2” U notch or greater
These are general recommendations – always follow manufacturer instructions for thinset mortars as well.
Types of Notched Trowel Patterns
There are a few common notched trowel patterns:
- Square notch – uniform square ridges. Good for absorbing substrates.
- U or Half Moon notch – rounded notches, allowing for more mortar spread. Better for large tiles.
- Euro notch – deeper center ridge with shallower outer notches. Combines deep and shallow spread.
Make sure to use the recommended notch shape for the tile and thinset type you select.
How to Choose a Trowel Size
Follow this process to determine the right trowel size:
- Consider tile size – mosaic, standard or large format tile.
- Determine what material the tile is – natural stone, ceramic, porcelain, glass.
- Identify the substrate you are tiling onto – cement board, existing tile, drywall.
- Consult manufacturer instructions for mortar regarding trowel size.
- Select notch size and shape based on factors above – 1/4″, 1/2″ square or U notch.
If between sizes, choose the larger size to ensure proper coverage. It is better to apply excess mortar than not enough.
Proper Use of Notched Trowel
Once you’ve selected the right trowel, proper technique is key:
- Hold trowel at a 45° angle to rake ridges uniformly.
- Apply even pressure to maintain depth.
- Spread only enough mortar for one or two tiles to prevent drying.
- Use the flat side to back-butter large tiles.
- Maintain ridges – don’t flatten notches.
- Discard and reapply if mortar skin forms.
Test adhesion by lifting a tile and inspecting coverage after applying. Adjust trowel angle or pressure to improve ridges.
Trowel Size FAQs
What size notched trowel for 12×24 inch tile?
For large format 12×24 inch tiles, use a 3/4″ by 9/16″ U-notched trowel.
What size notched trowel for penny round mosaic?
For small penny round mosaics, a 1/4″ by 1/4″ square notch trowel is recommended.
What size notched trowel for 8×8 inch porcelain?
An 8×8 inch porcelain tile will require a 1/2″ by 1/2″ square notch trowel.
What size notched trowel for backsplash on drywall?
For drywall, increase notch size slightly – use a 1/4″ x 3/8″ trowel for standard subway tile instead of 1/4″ x 1/4″.
Key Takeaways
- Choose trowel size based on tile size, tile material, and substrate.
- Mosaics need 1/4″ notch, standard tiles 1/4″ or 1/2″ U or square, large tiles 1/2″ or more.
- Match notch shape to substrate and mortar recommendations.
- Apply mortar properly holding trowel at consistent 45° angle.
- Too large is better than too small to ensure proper adhesion.
Carefully selecting and using the right size notched trowel will help guarantee a beautiful backsplash installation that lasts.