4×4 Half Bath Layouts
A 4×4 half bath is 16 sq ft (48″ × 48″) — room for a toilet and a sink. At this size an in-swing door always hits a fixture, so the plans are drawn with an out-swing door: Plan A then passes code clearances.
Plan A · Side by side
Rough-in sheet for your plumber
Where drains and supply lines go for Plan A in a 4′-0″ × 4′-0″ room. Measured from the finished face of each wall.
| Rough-in | Position | Notes |
|---|---|---|
| Toilet flange (center) | Back wall · 15″ from left wall · 12″ out from the wall | Standard 12″ rough-in · round-front bowl, 26″ deep |
| Sink drain | Back wall · 39″ from left wall | Wall-hung sink: add blocking in the wall · drain 18–20″ above floor (typical) |
Heights are typical values — confirm them against the spec sheets of the fixtures you buy.
Other half bath sizes
Adding a shower or tub? See full bathroom layouts.
Clearance rules used on this page
Based on International Residential Code minimums. Local codes can be stricter — confirm with your building department. How we check plans
Questions about 4×4 half baths
Is 4×4 big enough for a half bath?
Yes. Plan A fits a toilet and a sink with the code minimums: the toilet centerline 15″ from walls and fixtures, and 21″ of clear floor in front of the toilet and the sink.
Can the toilet and sink go on the same wall in a 4×4 half bath?
Yes — that's Plan A. Side by side on one wall keeps all the plumbing in a single wet wall, the cheapest option.
What size vanity fits in a 4×4 half bath?
A cabinet vanity doesn't fit with full clearances; use a compact 18″ × 14″ wall-hung sink instead (Plans A–C).
Which door works best in a 4×4 half bath?
An out-swing door. An in-swing door would hit the toilet or the sink in every layout, and the walls are too short for a pocket door.