Tile Work PhaseStep 20 of 27
Install Bathroom Floor Tile
Floor tile is one of the most visible elements of your bathroom. Careful layout planning and proper technique ensure beautiful, long-lasting results.
Quick Summary
Time Needed
4-8 hours
Cost
$300 - $800
Difficulty
Intermediate
Tools & Materials
Tools
- • Tile wet saw or score-and-snap cutter
- • Notched trowel (size based on tile)
- • Margin trowel
- • Tile spacers
- • Tile leveling system (optional but helpful)
- • Mixing bucket and drill paddle
- • Level (2-4 ft)
- • Tape measure
- • Knee pads
Materials
- • Floor tile (plus 10-15% extra)
- • Thinset mortar (modified for most substrates)
- • Tile spacers (1/8" or 1/16" typical)
- • Chalk line or laser level
Trowel Size Guide
| Tile Size | Trowel Notch |
|---|---|
| Up to 4" × 4" | 1/4" × 1/4" square notch |
| 4" × 8" to 8" × 8" | 1/4" × 3/8" square notch |
| 12" × 12" | 1/2" × 1/2" square notch |
| 16" × 16" and larger | 1/2" × 1/2" square + back butter tile |
Step-by-Step Installation
1
Plan Your Layout
Dry-lay tiles without adhesive to plan the layout:
- Start from the most visible wall (usually opposite door)
- Check that cut tiles at walls are roughly equal on both sides
- Avoid narrow slivers (less than half a tile) at walls
- Mark your starting line with chalk or laser level
- Plan for toilet flange, floor drain, and threshold
Pro tip: Measure twice, cut once. Spend time on layout—mistakes here affect the entire floor.
2
Prepare the Surface
- Sweep and vacuum floor thoroughly
- Verify floor is flat (max 1/8" deviation in 10 ft)
- Use self-leveling compound for significant low spots
- Ensure waterproof membrane is complete and cured (if applicable)
3
Mix Thinset
- Follow package directions for water ratio
- Mix to thick, creamy consistency
- Let slake (rest) for 10 minutes
- Remix briefly without adding water
- Mix only what you can use in 30-45 minutes
4
Spread Thinset
- Apply thinset with flat side of trowel first (key coat)
- Comb with notched side at consistent 45° angle
- Comb lines should all go the same direction
- Work in small sections (2-3 sq ft at a time for beginners)
- Don't spread more than you can tile in 15-20 minutes
5
Set Tiles
- Place tile into thinset with slight twisting motion
- Push perpendicular to trowel lines to collapse ridges
- Use spacers between tiles for consistent joints
- Check level frequently—tiles must be flat to each other
- Adjust within 15 minutes before thinset skins over
- Use leveling clips for large format tile (12"+)
6
Cut Perimeter Tiles
- Measure each cut individually (walls aren't perfectly straight)
- Leave 1/8" gap at walls (covered by baseboard)
- Use wet saw for clean cuts on porcelain
- Cut L-shapes and notches with multiple straight cuts
- Test-fit cut pieces before applying thinset
7
Clean and Cure
- Scrape any thinset from tile faces before it dries
- Clean thinset from joints (grout needs 2/3 depth minimum)
- Remove spacers after thinset sets (about 1 hour)
- Wait 24-48 hours before walking on floor
- Wait 24 hours before grouting
Common Mistakes to Avoid
- ✗Spreading too much thinset at once (it skins over and loses bond)
- ✗Not back-buttering large format tile (leads to hollow spots)
- ✗Skipping dry layout (results in awkward cuts)
- ✗Walking on fresh tile (causes tiles to shift and crack)
- ✗Using wrong trowel size (too small = hollow tiles, too large = squeeze-out)
Frequently Asked Questions
What size trowel for bathroom floor tile?
Use a 1/4" × 1/4" square-notched trowel for tiles up to 8", a 1/4" × 3/8" for tiles 8-12", and a 1/2" × 1/2" for larger format tiles. The goal is to achieve 95%+ coverage on the tile back when set.
Where do I start laying bathroom floor tile?
For small bathrooms, start at the most visible wall (usually opposite the door) and work toward the door so you can exit without stepping on fresh tile. Dry-lay first to ensure cut pieces at walls are roughly equal and no cuts are too narrow.
How long before I can walk on new floor tile?
Wait at least 24 hours before walking on newly installed floor tile, though 48 hours is safer. Check your thinset packaging for specific cure times. Rapid-set thinset may allow foot traffic in 4-6 hours.