Projects / 81 cards
Remodel a bathroom
The dimensions that make a bathroom usable, then the plumbing, waterproofing and drainage behind the tile, then the fixtures and finishes. Most bathroom failures are water getting somewhere it shouldn’t.
026 cards
Before framing
Room sizes, openings, stairs, ceiling heights and anything structural. Cheap on paper, expensive once the walls are up.
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Shower
Bathroom dimensions you should know
- code: 900 sq in, no side under 30″
- good: 36 × 36″ or larger
- 24″ clear in front (code), 30″ good
Door
Bathroom dimensions you should know
- 32″ door, more for accessibility
- swing clear of fixtures
- outward or pocket doors help small rooms
Shower niche
Bathroom dimensions you should know
- fits a stud bay: about 14½″ wide
- 12–24″ tall
- about 3½″ deep in a 2×4 wall
Curbless shower
Drainage, floor slope and traps
- no step into the shower
- floor recessed or built up
- best for aging in place
Niche
Shower areas and fittings
- recessed niche: sizes on the dimensions spread
- keep it off the exterior wall
0311 cards
Before rough-in
Where pipes, wires, ducts and boxes go, before the inspector signs off on them.
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Around the toilet
Bathroom dimensions you should know
- 15″ center to side (code), 18″ good
- 21″ in front (code), 30″ good
Sink + vanity
Bathroom dimensions you should know
- center to side wall: 15″ code, 20″ good
- two sinks: 30″ center to center minimum
- vanity height 32–36″ typical (NKBA: 32–43″)
Shower heights
Bathroom dimensions you should know
- head about 80″ (custom for tall users)
- controls 38–48″ (NKBA)
Shower valve
The plumbing behind the wall
- one valve mixes hot and cold
- pressure-balance or thermostatic
- prevents scalding when someone flushes
Concealed vs exposed
The plumbing behind the wall
- concealed: the US norm, clean look
- exposed: clawfoot tubs, retrofits
Linear drain
Drainage, floor slope and traps
- one-way slope, so large tiles work
- clean modern look
- good for curbless showers
044 cards
Before drywall
Blocking, insulation, fire blocking and anything else that lives inside the walls.
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Grab bars
Shower areas and fittings
- install blocking now, bars later
- rated to carry body weight
- 33–36″ high is typical
0511 cards
Before tile + floors
Waterproofing, backer board and floor prep that go under the finish you see.
BathroomsFree
Where to waterproof
Waterproofing in bathrooms
- shower walls: full height (code: nonabsorbent finish to at least 6 ft)
- the entire shower floor
- tub walls with a shower head
Critical details
Waterproofing in bathrooms
- floor-to-wall corners
- pipe and valve penetrations
- drain connection
Flood test
Waterproofing in bathrooms
- plug the drain, fill toward the curb
- wait 24 hours, check below (code minimum is 15 minutes)
- before any tile goes down
Shower floor slope
Drainage, floor slope and traps
- ¼″ per foot minimum
- ½″ per foot maximum (code)
- use smaller tiles on a center drain
0649 cards
Throughout the job
Choices and checks that aren’t tied to one stage. Settle them early, or check them as the work goes.
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Single wall
Which bathroom layout works?
- all fixtures share one plumbing wall
- cheapest to build
- works in long, narrow rooms
Classic 5 × 8 full bath
Which bathroom layout works?
- the standard American hall bath
- 60″ tub/shower across the end
- toilet and vanity side by side
Parallel
Which bathroom layout works?
- fixtures on two facing walls
- good for medium rooms
- keeps wet and dry sides apart
L-shaped
Which bathroom layout works?
- uses corners efficiently
- tucks the shower away
- small to medium rooms
Wet + dry zones
Which bathroom layout works?
- shower behind glass or a wall
- the rest of the room stays dry
- easier to clean
Powder room (half bath)
Which bathroom layout works?
- toilet and sink only
- no shower, so less waterproofing
- a place for a statement sink or mirror
Family bath
Which bathroom layout works?
- built for several users
- double vanity eases mornings
- more storage
Primary bath
Which bathroom layout works?
- separate tub and shower
- often a private toilet room
- feels open and calm
Movement space
Bathroom dimensions you should know
- 30″ clear at each fixture
- 60″ circle for a wheelchair
Mirror
Bathroom dimensions you should know
- center about 60–65″ off the floor
- bottom a few inches above the faucet
Accessories
Bathroom dimensions you should know
- paper holder: 26″ high, 8–12″ ahead of the bowl
- towel bar: about 42–48″
- robe hook: about 66–70″
Liquid-applied
Waterproofing in bathrooms
- painted on in coats
- seamless, good around details
- meets ANSI A118.10 when listed
Sheet membrane
Waterproofing in bathrooms
- bonded with thinset
- consistent thickness
- pairs with matching drains
Traditional pan liner
Waterproofing in bathrooms
- PVC or CPE liner over a pre-slope
- the old-school mud shower
- needs clear weep holes at the drain
P-trap
Drainage, floor slope and traps
- holds a water seal against sewer gas
- 2″ minimum seal
- on every sink, tub and shower
Bench
Shower areas and fittings
- 17–19″ high, about 15″ deep
- slope the top to drain
- great for shaving and aging in place
Exhaust fan size
Comfort, air and extras
- code: 50 CFM minimum
- guideline: about 1 CFM per sq ft for rooms up to 100 sq ft
- a fan near the shower and in a toilet room
Kitchen, Bathroom and Stairs are open to everyone. The rest are in the full fieldbook.
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