4-1/4" and some larger wall tiles have bumps cast in that act as spacers. Unless you want a larger gap, no additional spacers are needed.

Whether your particular tile has them is uncertain. They're often necessary to prevent sagging with heavier tile while the mortar or mastic sets.

Answer from isherwood on Stack Exchange
🌐
The DIY Playbook
thediyplaybook.com › home › diy index › 10 tips for installing subway tile
10 Tips To Install Subway Tile In Your Bathroom
August 17, 2023 - Yes. Most subway tile has grooves on the sides so you don’t need to use spacers at all because it’s an automatic 1/16″ grout line.
🌐
Fine Homebuilding
finehomebuilding.com › do subway tiles need to be spaced?
Do Subway Tiles Need to Be Spaced? - Fine Homebuilding
August 4, 2025 - ... Oregon tile contractor Joshua Oduin replies: Good news: You can install subway tile both ways. It depends on the brand of tile and the look you want to achieve. Subway tile made by Dal-Tile or American Olean, for example, has a small built-in ...
🌐
Houzz
houzz.com › discussions › 5399580 › what-size-tile-spacers-for-shower-subway-tile-on-walls
What size tile spacers for shower subway tile on walls?
I like the look of 1/16” (1.5mm), but the Internet is telling me 2-3mm to allow for stress movement. The current shower uses 4x4 tile with shower pan and the grout lines look like they range from 1/32 to 1/16”. There are vertical stress cracks in a couple of the lower tiles which I assume ...
🌐
Reddit
reddit.com › r/homeimprovement › tiling questions - 3x6 subway tile in shower
r/HomeImprovement on Reddit: Tiling questions - 3x6 subway tile in shower
December 17, 2017 -

I've tiled floors before and am very happy with the way they came out, but this is my first shower.

I'm using a KBRS shower slope base and redgard waterproofing membrane.

I've asked these questions at the tile store and have watched a bunch of videos and of course get different answers. I'm interested in seeing what r/homeimprovement thinks.

The shower is about 61" wide by 33" deep. The opening for the door is 34" so the front wall is about 34" open and a 27" wall.

  1. What height should my shower curb be?

  2. Should I tile on the outside of the curb? The curb will have a marble cap on it, sloping inward, and the inside vertical of the curb will be tiled. But the outside vertical (about 3") is facing the rest of the bathroom. Is it OK for that to be covered in drywall, or should it be tiled too?

  3. Inside corners - how much of a gap do I leave from one wall to the other when they meet on an inside corner? Or do I just butt them up against each other since I will be caulking the corners anyway?

  4. self-spacing or no? Many 3x6 subway tiles have built in lips that act as 1/16" spacers. Or I could purchase tile that needs spacers. it seems like the built-in spacers would be quicker and easier but I'm just wondering what opinions are on it.

Thanks!

Top answer
1 of 5
9
Built in tile spacers are ok if your stacking the tile. Lots of people do brick pattern with subway tile so id recommend using spacers. You can do it without if you have a good eye and control lines marked out but for a DIY i would advise against this method. Personally i would tile the outside of the curb in the same tile you used on the floor and line up the joints if possible. Curb height is your own choice unless you have a building code where you live. Lots of people like a low profile curb. Schluter systems makes pre fab curbs (high density foam) and you can rip them too your desired height. They are installed with mortar and stand up alot better then wood curbs. The inside wall joints should be no fatter then a grout joint but I like to cut the tile as tight as possible. Your using redguard paintable membrane? Its an ok choice but im kind of a Schluter guy and like the cloth membrane they provide. 2 inch over lap everywhere and your golden. They also provide pre formed inside and outside corners.
2 of 5
3
Smeffrey covered most of it. I would just add that if you rock the outside curb you still have to use cove mould so why not tile it? As a general rule you cut the tile spacing in half for an inside corner, but no less than 1/16". When you say caulk I hope your using matching tile caulk. You need a gap for it just as you would for grout. No fillets! You didn't mention the floor tile. In order for the tile to lay down across the slope changes I never use a tile bigger than 2".
🌐
Houzz
houzz.com › discussions › 2672345 › help-do-i-need-spacers-for-american-olean-3x6-subway-tiles
Help! Do I need spacers for American Olean 3x6 subway tiles?
We used the same tile for our kitchen backsplash. Please use the spacers (check to see what is recommended grout line and get spacers that size). if you want a uniform look, then choose a grout color that best blends with the tiles.
🌐
NIUYUAN Trims
niuyuantrims.com › need-spacers-for-subway-tiles
Do You Need Spacers For Subway Tiles - NIUYUAN
July 8, 2025 - For subway tiles, this means consistent spacing. Without spacers, even slight variations can add up. This can make your lines look wavy or uneven. This is especially true for longer runs of tile, like a big kitchen backsplash or a full shower wall.
Find elsewhere
🌐
Reddit
reddit.com › r/homeimprovement › subway tile install without spacers
r/HomeImprovement on Reddit: Subway tile install without spacers
April 12, 2018 -

My contractor installed 3x12 tiles in my shower, and while the grout lines are straight, the tiles seem to be unlevel. I don’t recall seeing any spacers used like he did on the floor. He’s blaming the wall for being uneven but it’s all new! I have the worst luck with contractors, even with reviews!

https://streamable.com/mo5stj

See comment below with new videos of replaced cement board

🌐
Home Repair Tutor
homerepairtutor.com › subway tile shower niche tips
Subway Tile Shower Niche Tips - Home Repair Tutor
November 25, 2023 - So it’s critical to make the first row as level as possible. And I recommend using a laser level to accomplish this. In addition, use spacers between the first row of tile and your shower tile floor.
🌐
Green Tile
edwardmartin.com › home › information › information
A Closer Look At Subway Tile Applications In Bathroom Showers
June 13, 2024 - Begin placing the subway tiles at the lowest part, pressing them firmly into the mortar and progressing upwards. Insert spacers as you go to maintain uniform gaps between the tiles.
🌐
Erin Zubot Design
erinzubotdesign.com › home › how to install tile in your bathroom shower, step by step
How to Install Tile in your Bathroom Shower, Step by Step - Erin Zubot Design
April 28, 2024 - Make sure you use tile spacers at your desired width to space the tiles apart, I wanted fairly small grout joints so I used 1/16” spacers. Add your next tile tight to the tile you just installed, and use the spacer to press between the tile, ...
🌐
Vintage Revivals
vintagerevivals.com › home › lessons i learned while installing subway tile cause i’m an idiot.
Lessons I Learned While Installing Subway Tile Cause I’m an Idiot. • Vintage Revivals
June 18, 2019 - When you tile from the bottom up the baseboard give it stability and then the spacers make it so that you can build up. Such a great question!! ... The end result was definitely worth the hard work, it looks awesome! https://www.theartfulscavenger.com/#!Designer-Peeves/cmbz/5697dd6a0cf2e94e3fb7a77c ... Turned out great! We have subway tile in our kitchen and I love it.
🌐
The Craftsman Blog
thecraftsmanblog.com › home › the ultimate guide to subway tile
The Ultimate Guide to Subway Tile - The Craftsman Blog
May 3, 2022 - Some subway tile have spacers on the edges to give them the proper spacing and some require the use of plastic spacers until the mortar dries.
🌐
Reddit
reddit.com › r/home › tiling with no spacers? contractor says it’s not necessary. am i missing something? lines definitely don’t look straight.
r/Home on Reddit: Tiling with no spacers? Contractor says it’s not necessary. Am I missing something? Lines definitely don’t look straight.
November 29, 2021 - There are tiles that don't require spacers. Subway tiles have a thin flange built into them so that when they're installed without spacers they have a space between them for grout still.
🌐
Quora
quora.com › Do-you-need-spacers-for-subway-tiles
Do you need spacers for subway tiles? - Quora
Answer: If the tiles have spacers molded into their edges (you’ll see and feel two bumps on each edge of the tile), then no, you do not need spacers unless you want a wider grout line than the built-in spacers provide.
🌐
DIY Home Improvement
diychatroom.com › home › forums › home improvement › remodeling › kitchen & bath remodeling
Subway Tile - spacers | DIY Home Improvement Forum
Some subway tiles have the spacing built in and some don't. Here is a good picture for you to reference, this is from my bathroom that I just finished. This is with 1/8" spacers. The grout lines are a little wider than I thought they would look ...
🌐
Reddit
reddit.com › r/tile › first timer - diy subway tile shower - looking for input on inside corner lines
r/Tile on Reddit: First timer - DIY subway tile shower - looking for input on inside corner lines
August 26, 2022 - Good to go maybe ⅓ up on all sides, then another ⅓, or whatever. Spacers are a guide, they don't do all the work for you. ... Tiles are not all exactly the same size, so spacers can get you off track sometimes.