How to use the bathroom clearance guide
Bathrooms are the tightest rooms in a house, and a toilet that is 2 in too close to a vanity can fail an inspection. This checker compares the dimensions on your plan with the minimum fixture clearances in the International Residential Code and the clearances the National Kitchen & Bath Association recommends, and tells you what passes. Leave a field empty to skip a check.
- Choose units and enter dimensions from the centerline of each fixture or from its front edge, as labelled.
- Enter toilet and lavatory clearances: centerline to the nearest side wall or fixture, and clear space in front.
- Enter shower size and the opening width, and the space in front of the opening.
- Say whether a door swing crosses a clear space.
- Read the result: Fail means below the code minimum; Code means it meets the minimum; Code and NKBA means it also meets the recommendation.
Minimum clearances
Toilet: centerline ≥ 15 in from side wall or vanity; ≥ 21 in clear in front
Fixtures side by side: ≥ 30 in center to center
Lavatory: centerline ≥ 15 in from side; ≥ 21 in in front
Shower: ≥ 900 in², least dimension ≥ 30 in, opening ≥ 22 in, ≥ 24 in in front
Tub: ≥ 21 in clear in front
These come from IRC 2021 Figure R307.1 and Sections P2705.1 and P2708.1, as summarized by the NKBA Bathroom Planning Guidelines; the metric values are straight conversions.
| Item | Code minimum | NKBA recommended |
|---|---|---|
| Toilet centerline to side | 15 in (381 mm) | same |
| Clear in front of toilet or basin | 21 in (533 mm) | 30 in (762 mm) |
| Fixture center to center | 30 in (762 mm) | same |
| Shower interior | 30 × 30 in, 900 in² | 36 × 36 in (914 mm) |
| Shower opening width | 22 in (559 mm) | same |
| In front of shower opening | 24 in (610 mm) | 30 in (762 mm) |
Worked examples
A compact guest bath
A toilet is centered 17 in from the side wall, with 20 in of clear space before the vanity. The 17 in centerline distance passes the 15 in minimum, but the space in front needs 21 in, so it fails by 1 in. Moving the vanity 1 in, or choosing a shallower vanity, fixes it.
Toilet next to a basin
Centerlines 28 in apart fail the 30 in center-to-center rule. Shift the basin 2 in or use a smaller vanity, and check the basin is still 15 in from the side wall.
A 32 × 32 in shower
The area is 1,024 in², above the 900 in² minimum, and the least dimension is 32 in, above 30 in. With a 22 in opening and 24 in of space in front it passes the code. It does not reach the NKBA 36 × 36 in recommendation.
Who this guide helps
- Architects and designers checking plan layouts before drawings go to the building department.
- Remodelers and plumbers setting rough-in locations.
- Developers and agents assessing whether a small bathroom can be reconfigured.
- Homeowners planning a renovation.
Practical tips
- Count the fixtures required for a building type with the plumbing fixture calculator, and check exhaust flow with the ventilation rate calculator.
- Plan wet-area finishes using the tile calculator and the grout calculator.
- Measure from the finished wall surface; tile and backer add thickness that eats clearance.
- Check door swings and pocket-door options early; a door is the most common reason a small bath fails.
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