Elegant and bright small bathroom

How to Measure for the Perfect Bathroom Renovation

A bathroom renovation can transform the most functional room in the house into a calming and relaxing space. Starting with the right measurements is crucial for success, and there are standards for the size and location of fixtures you need to stick to as well. Let’s get started.

Bathroom Layout

Entry door

Door openings—including entrance, cabinet, and shower doors—must not interfere with the functionality of bathroom fixtures or the use of other doors.


  • Door clearance: 32"
  • Opening width: 34" recommended, 32" minimum



  • Height in front of sanitary fixtures and vanity (middle of the room): 80"
  • Height behind sanitary fixtures and vanity (along the wall): 60"

Electrical outlets, switches, and lighting

All outlets in a bathroom must have GFCI protection (ground fault current interrupter).


  • Height: 39" above floor
  • There needs to be at least one outlet within 36" of the sink edge


  • There must be at least one switch located at the bathroom entrance
  • Switches must not be within reach of the bath or shower


  • Any lighting located above a bathtub must be at least 36" away from the rim horizontally or 8’ above the rim vertically


  • CFM (cubic feet per minute) is a measure of airflow. If you do not have a central air ventilation system, then you will need a bathroom fan with a minimum exhaust rate of 50 CFM
Illustration of a bathroom layout

Vanities and Pedestal Sinks



  • Width: from 18" up to 72"
  • Height: 32" to 43" including the counter. 30" to 32" for vessel sinks
  • Depth: 21"

Vanity clearance in front: 21" minimum but 30" recommended for a 51" total from the wall

Drop-in sink clearances

  • Width: 30" to 36"
  • Front: 30" recommended, 21" minimum
  • Wall: 20" recommended from the centre of the drain, 15" minimum
  • Double sink: 36" recommended from the centre of the drain, 30" minimum for a total vanity width of at least 60"

Pedestal sink

A preferred choice for small bathrooms to maximize available circulation space.


  • Height: 33" standard
  • Depth: 22" maximum
  • Width: 24"


  • Wall: 4" from the rim and at least 15" from the centre of the drain
  • Front: 30" recommended, 21" minimum
  • Double sink: 4" from the rim and at least 30" from the centre of the drain
Illustration of a bathroom vanity with standard dimensions
Illustration showing standard bathroom mirror position




  • Tank width: 21" for standard toilets, 15" for compact toilets
  • Bowl height: 15" for standard toilets with a 16" seat; 17" to 19" for comfort-height toilets; 11" for children’s toilets
  • Total depth: 25" to 29" for short or round toilets; 28" to 31" for elongated toilets
  • Total height with tank: 30" to 39"
  • Rough plumbing: standard is 12" from wall; 10" and 14" available as well


  • Wall: 4" minimum
  • Width: 30" to 36"
  • Front: 30" recommended, 21" minimum

Toilet paper holder

  • Distance from front of toilet: 8" to 12"
  • Height from floor: 26" to 30"

Grab bars


  • Width: 36" minimum


  • Width: 42" minimum
  • Depth from back wall: 12" maximum
Illustration of adequate clearance around a toilet




  • Width: 32" standard but can vary from 30" to 42"
  • Length: 60" standard but long models can extend to 72"
  • Water depth: 15" and 16" standard, 16" for more for greater depth, and 13" for those with reduced mobility


  • Side: 16"
  • Front: 21" minimum, 30" recommended, 60" for increased accessibility

Clawfoot tub: must be installed at least 4" from the wall

Drop-in tub: supporting base must not be higher than 22"

Location of bathtub faucet

  • Within the rim of the bathtub to allow for easy access
  • Height: 33" above floor
Illustration showing standard bathtub dimensions
Illustration showing adequate clearance around a bathtub
Illustration showing the standard height of a bathtub




  • Width: 36" recommended, 30" minimum
  • Length: 36" recommended, 30" minimum
  • Edge to floor: 3" to 4" standard, 4" to 6" wide
  • Waterproof wall cladding: 72"

Corner shower: 32" X 32" minimum


  • Front: 30" recommended, 24" minimum

Location of shower faucet

  • Faucet height: 38" to 48" above shower floor
  • Shower head height: 66" to 81" above shower floor

Safety bar: height of 33" to 36" above floor

Illustration of a shower with dimensions

Storage and Accessories


  • Height: 40" to 42" above the floor, with the centre at 65" above the floor for approximate eye level. Tilt mirrors should be 48" above the floor

Towel hooks and bars

Install one towel bar for each person using the bathroom.

  • Hook height: 66"
  • Bar height: approximately 36"

Width is dependent on each model.

Grab bar

Grab bars should be anchored to studs so they are capable of supporting up to 300 lb.

  • Height: 33" to 36" above floor
  • Recess: 1½" from wall
  • Diameter: 1½"

Linen cabinets


  • Width: 18" to 36"
  • Height: 84" to 90"
  • Depth: 21" and 14" (minimum depth for easy towel folding)

While You’re At It