B
HomeLibrariesCode AISearchProjectsBookmarksAddress
FeedbackHelp Desk
Libraries
Code LibraryDiagramsAssembliesProductsCalculatorsChecklistsCSI MasterFormat SpecificationsPermitsAddress ReportDOT SpecsModel CodesTransportationRailroadFire SafetyAccessibilityStructuralTransit SpecsUSACE
Other Jurisdictions
Transportation
MUTCDFHWA FP-14
Accessibility
ADA StandardsPROWAG
PricingLog in
Home / Code Guides / Bathroom Clearances

Bathroom Fixture Clearances — The 15/21/24-Inch Rules

Bathroom layouts are governed by three small numbers — 15, 21, and 24 — measured from fixture centerlines and faces. They are the difference between a legal powder room and a drawing that will not pass plan review.

RequirementModel Code StandardSection
Toilet side clearance15 in. minimum from the water closet centerline to any wall, partition, vanity or other fixture — 30 in. total between fixtures set center-to-centerIRC R307.1, Fig. R307.1
Front clearance21 in. minimum clear space in front of the water closet, lavatory and bidetIRC R307.1
Shower access24 in. minimum clearance in front of the shower openingIRC R307.1
Ceiling height6 ft 8 in. over the fixture and at the showerhead; sloped ceilings can eat a tub alcove fastIRC R305.1
VentilationAn openable window of 1.5 sq ft or a mechanical exhaust of 50 cfm intermittent / 20 cfm continuous vented outdoorsIRC R303.3, M1505
ReceptacleAt least one GFCI-protected receptacle within 36 in. of each basinNEC 210.52(D), 210.8(A)

Worth knowing

  • The 15 in. is to centerline, not to the toilet edge — a 30 in. alcove is the practical minimum, and comfort-height elongated bowls make tight alcoves feel smaller still.
  • ADA/accessibility dimensions (60 in. turning, 16–18 in. toilet centerline off the side wall) apply to covered public facilities, not private homes — do not mix the two rule sets.
  • Pocket doors solve the majority of small-bath front-clearance conflicts with in-swinging doors.
  • The bath fan must terminate outdoors — not in the attic. Attic-dumped fans are a mold generator and an inspection failure (M1501).
Sections cite the 2021 International Residential Code and 2023 National Electrical Code as model standards. This is BuildSpec’s own summary — not ICC or NFPA text; read the authoritative language at codes.iccsafe.org. Your state may be on a different edition with amendments — check your jurisdiction page or get an Address Report.
Deck Footings →Deck Ledger →GFCI Protection →Egress Windows →Stairs →Handrails & Guards →