How to measure your bathroom
- Wall to wall, both ways. Measure at floor level, just above the baseboard, and write down the smaller number if the walls aren’t square.
- The door. Note which wall it’s on, how far its opening starts from the nearest corner, the door’s width, and whether it swings in, swings out or slides.
- The plumbing wall. Note the wall with the drain and supply lines. Keeping the toilet, sink and tub on it costs the least to plumb.
- The fixtures. Check the depth of the toilet you’ll buy, from the wall to the front of the bowl: about 28 in for a round bowl and about 30 in for an elongated one on Kohler’s and TOTO’s sheets. Check the vanity, tub or shower base on its maker’s sheet too.
How to design a bathroom layout in five steps
- Start from the plumbing wall. One wall with the toilet, sink and tub or shower is the cheapest plan to build. Moving a toilet drain is the most expensive change in a remodel, so the planner ranks layouts with fewer plumbing walls first.
- Settle the door. A 30 in door that swings into a 5 ft wide room sweeps half its width. If nothing fits, try hinging it on the other side, swinging it out or a pocket door.
- Place the biggest fixture first. A 60 in tub or shower usually runs wall to wall across one end of the room.
- Fit the toilet and the vanity with their clear space. The code asks for 15 in from the toilet’s centerline to a wall or the next fixture and 21 in of clear floor in front of the toilet and the sink. Designers aim for 18 in and 30 in.
- Add storage that doesn’t take floor. A recessed medicine cabinet, a shower niche or shelves over the toilet leave the clear spaces open.
What the planner checks
Every layout is checked at three levels. A layout “fits” when it passes the code minimum; the comfortable and accessible levels show what a roomier or a wheelchair-ready bathroom would need.
| Check | Code minimum | Comfortable | Accessible |
|---|---|---|---|
| Toilet centerline to a wall or fixture | 15 in (IRC R307.1) | 18 in (NKBA) | 16 to 18 in to a side wall (ADA 604.2) |
| Clear floor in front of the toilet | 21 in (IRC R307.1) | 30 in (NKBA) | 60 × 56 in around the toilet (ADA 604.3.1) |
| Sink centerline to a wall or fixture | 15 in (IRC R307.1, P2705.1) | 20 in (NKBA) | Not set |
| Two sinks, center to center | 30 in (IRC P2705.1) | 36 in (NKBA) | Not set |
| Toilet to a sink beside it, center to center | 30 in (IRC P2705.1) | Not set | Not set |
| Clear floor in front of a sink or vanity | 21 in (IRC R307.1) | 30 in (NKBA) | 30 × 48 in (ADA 305.3, 606.2) |
| Clear floor in front of a shower | 24 in (IRC R307.1) | 30 in (NKBA) | Depends on the shower type (ADA 608.2) |
| Shower floor | 900 sq in, at least 30 in across (IRC P2708.1) | 36 × 36 in inside (NKBA) | Transfer 36 × 36 in; roll-in 30 × 60 in (ADA 608.2) |
| Clear floor in front of a washer and dryer | Room to open the doors: about 25 in, or 21 in for 24 in machines (makers’ sheets) | 36 in (NKBA walkway) | 30 × 48 in, side approach (ADA 611.2) |
| Turning space | Not set | Not set | A 60 in circle (ADA 304.3) |
| Door | No minimum width for a bathroom door (IRC R311.2 covers the exit door only) | 32 in clear (NKBA) | 32 in clear (ADA 404.2.3) |
NKBA numbers come from the National Kitchen & Bath Association’s free bath planning guidelines; its newer, paid editions ask for a little more in places, such as a 34 in clear door opening. A door’s clear opening is about 2 in less than the door itself, so a 34 in door gives about 32 in. The planner also checks that each fixture is inside the room, nothing overlaps, the door can open and there’s a path at least 18 in wide from the door to every fixture (our own floor, not a code rule). Codes are adopted and amended locally: your building department has the final say.
How the planner reads the spacing rules for a sink. A wall, a shower wall, a partition, a linen cabinet or another sink counts beside a sink for its 15 in. A tub’s low rim doesn’t, and neither does a toilet on the other side of a vanity cabinet: the cabinet separates them, and the toilet keeps its own 15 in from the cabinet. A toilet and a sink side by side on one wall still need 30 in from center to center, cabinet or not, because the code counts them as adjacent fixtures (P2705.1). Inspectors don’t all read these rules the same way, so check with yours.
Start from a measured layout
Each layout guide has plans drawn by this planner, ready to open and adjust: bathroom layout ideas by room size, small bathroom layouts, 5x8 bathroom layouts, 5x7 bathroom layouts, 8x8 bathroom layouts, master bathroom layouts, layouts with a tub and a separate shower, long narrow bathroom layouts, Jack and Jill bathrooms, 3/4 and half baths, half bath dimensions, powder room layouts and ADA bathroom layouts.
What the planner doesn’t do
- It doesn’t design plumbing, venting or wiring. Moving a drain or a vent, and any electrical work, is a job for a licensed plumber or electrician, usually with a permit.
- It draws rectangular rooms with fixtures against the walls, and no angled walls. Plans from our layout guides can add a partition wall (for a toilet room) or a freestanding tub, and they open here too, but the form doesn’t place those for you yet.
- Fixture sizes are typical nominal sizes. Check the spec sheet of what you buy, especially the toilet’s depth and the shower base’s inside size.
- Corner (neo-angle) showers come in 38 and 42 in sizes, drawn with a typical angled front. There’s no 36 in one: MAAX lists its 36 in neo-angle base at 29⅝ in inside, under the code’s 30 in.
- It follows the model codes. Your city or county may have amended them.
Questions
How do you design a bathroom layout?
Start from the wall that has the plumbing, settle the door, place the tub or shower first, then fit the toilet and vanity with 15 in from the toilet’s centerline to anything beside it and 21 in of clear floor in front of each. The planner does all of this for you and shows every arrangement that passes.
How much space do you need around a toilet?
At least 15 in from the center of the toilet to a side wall or the next fixture, and 21 in of clear floor in front of it, under the 2021 International Residential Code (R307.1). The NKBA recommends 18 in and 30 in for a comfortable bathroom.
Can the bathroom door swing over the toilet?
The residential code doesn’t forbid a door swinging over a fixture’s clear floor, but the door can’t hit the fixture itself. The planner flags a door that hits a fixture and suggests swinging it the other way, out, or switching to a pocket door. Accessible bathrooms have stricter rules (ADA 603.2.3).
Does a tub need clear space in front of it?
The 2021 International Residential Code sets no clear space for a tub, only for toilets, sinks and showers. The planner still checks that you can walk from the door to the tub.
How wide does a bathroom door have to be?
The residential code sets no minimum for an inside door such as a bathroom door; only the main exit door needs 32 in (IRC R311.2). The NKBA recommends a 32 in clear opening, and accessible bathrooms need one (ADA 404.2.3), which takes a 34 or 36 in door.
Is the planner free, and do I need an account?
Yes, it’s free, and there’s no account. Plans you save go to My bathroom in your browser, and a share link carries the whole plan in the address.
Can I use centimeters?
Yes. Switch to cm at the top of the page: the fields, the drawing and the checks all change over.
Sources
- 2021 International Residential Code, chapter 3 (R307.1 fixture clearances, R311.2 doors), read in Colorado’s adoption without amendments on UpCodes, October 2026.
- 2021 International Residential Code, chapter 27 (P2705.1 fixture spacing, P2708.1 showers), same source.
- Larimer County, Colorado: Figure R307.1 bathroom clearances.
- U.S. Access Board: 2010 ADA Standards for Accessible Design, sections 304, 305, 404, 603, 604, 606, 608 and 611.
- NKBA’s free bath planning guidelines, the comfortable spacing. Its newer, paid editions change some numbers.
- Toilet depths from the wall, 12 in rough-in: Kohler Cimarron round and elongated, TOTO Drake round and elongated spec sheets.
- Alcove tubs: Kohler Underscore 60 × 30 in and 60 × 32 in spec sheets.
- Neo-angle shower bases: MAAX Neo-Angle Base 38 (38⅛ × 38⅛ in, 33½ in inside) and Neo-Angle Base 36 (29⅝ in inside); Kohler Memoirs K-9542, 42 × 42 in; and a 22 in walk-through on Sterling’s 38 in neo-angle shower kit.
- Washer and dryer sizes and clearances: LG WM4000H (27 × 30¼ in, 55 in deep with the door open, 78 in stacked), Samsung WF45B6300 washer and DVE45B6300 dryer (1 in at the sides and between, 5¼ in behind, 78½ in stacked), GE GFW148 24 in washer (66½ in stacked) and GFQ14 24 in washer-dryer combo, and Bosch WGB24600UC (23½ in wide, 67¾ in stacked) spec sheets.
- NKBA Kitchen & Bath Planning Guidelines, 4th edition summary: walkways at least 36 in wide.