Bathtub Door｜Glide B21

Shower Pans

Unlike the shower door measurements, which rely on fully finished surfaces, shower pan measurements are taken from the bare framing. All dimensions for the pan must be taken from the wall studs. This method is required because the pan is installed before the tile backer board and final finished wall surfaces are applied. Therefore, measure the width from stud to stud, the depth from the stud face to the outside of the intended curb (dam), and the location of the drain centerline from the nearest wall studs.

Shower/Bathtub Doors

Before you start, make sure you're measuring from fully finished walls or surfaces where the tile thickness has already been accounted for. Do NOT measure from bare studs.

First, use a 4-foot carpenter's level to check that your walls are perfectly plumb (vertical) and your base is level.

Vertical Opening ("A" Measurement)
Measure from the top of the shower or bathtub threshold up to the top edge of your finished wall (tile or acrylic surround).

Horizontal Opening/Width ("B" Measurement)

To ensure the best fit, you must measure the width of the opening in three specific places:

1. The Bottom
2. The Middle
3. The Top

Determining the Correct Width:

• If measurements are the same: Congratulations! You can select any standard door size that matches your dimensions.
• If measurements vary (Out of Plumb): If your walls are out of plumb or the measurements vary, you must use the smallest of your three measurements as the final width for ordering.
  • For example: If the top is 61 in, the middle is 60 in, and the bottom is 58 in, your correct width for ordering is 58 in.

Sill/Threshold Depth ("C" Measurement)
Measure the front-to-back depth of your shower or tub threshold. 

Additional Considerations:

Stud Location: Most AquivaCoast® doors need to be anchored into wall studs for secure installation. Please check your wall structure during the installation process.

Clearance Height: Check that there’s enough overhead clearance to tilt and install the glass panels.

Required measurements vary by product. For additional help, visit our FAQs or contact our Customer Support Team.