Rule of thumbRecommended
Full bathroom sizing
BATHROOM-MINDescription
Full bathrooms (toilet + sink + tub/shower) need ≥40-50 sqft for compliant fixture clearances. 35 sqft is the absolute minimum per IRC.
Why this exists
The IRC 35 sqft floor is functional but cramped; ~50 sqft is comfortable.
Categories
Bathroom
Applies to
- Room types: bathroom
Source
AIA / Ramsey-Sleeperno manifest entry
Architectural Graphic Standards (—)
Section: Residential layout chapters
Published 2024-01-01 · last verified 2026-05-09
Solver enforcement
Browsable only — the solver does not currently enforce this directive (no spec-level data to check against). This entry exists so the architect personas can cite it in conversation and the user can read what the rule says.
Related directives
- Half bathroom sizing · HALF-BATH-MIN
- Half bath near public zones · HALF-BATH-NEAR-PUBLIC
- Bath not opposite kitchen / dining · BATH-NOT-OPPOSITE-DINING
- Bathroom door not opposite kitchen / dining · ADJ-BATH-PRIVACY-01
- Primary bath adjoins primary bedroom · ADJ-PRIMARY-BATH-01
Last reviewed 2026-05-09.