Andersen® gliding patio doors have a part called a bottom rail filler that is applied to the bottom of the operating door panel. This part fills the gap between the bottom rail (the horizontal piece of the panel outside the glass at the bottom of a door panel) and the bottom sill (the horizontal piece at the bottom of a door frame that aligns with the floor). It contains a fuzzy-pile weatherstrip to establish a secure, weather-tight seal. You can only replace the fuzzy-pile weatherstrip by replacing the bottom rail filler.

Install Bottom Rail Filler on Andersen® 400 or 200 Series Gliding Patio Door

This article provides you with resources for ordering and installing a replacement bottom rail filler on a 400 or 200 Series gliding patio door.

Note: The bottom rail filler will look different depending on the height and performance grade rating of your patio door unit.

Safety Warning

Tools and Supplies Needed

• Safety glasses
• Phillips head screwdriver

Let's Get Started

1. Order Parts

Before ordering a replacement bottom rail filler, determine the size and exterior color of the gliding patio door.

• To determine your patio door size, see Determine the Size of Your Andersen® Window or Patio Door.
• To determine your patio door color, see Exterior Colors for Andersen® Windows and Patio Doors.

You can purchase a replacement bottom rail filler online from the Andersen Parts store.

Important: For assistance with a replacement bottom rail filler quote, replacement parts for gliding patio doors manufactured before 1982, or additional questions, Contact Andersen® Windows and Doors.

2. Install Parts

Important: Replacing the bottom rail filler will require the removal of the operating panel from the frame of the unit. Panels are extremely heavy, so make sure to use caution and proper lifting techniques. For assistance replacing a bottom rail filler, contact a Service Provider. For more information, see Locating Andersen® Window and Patio Door Service Providers.

1. Remove the operating door panel (the door that moves) from the frame of the unit by following the steps in the Panel Assembly and Installation Guide in reverse.
2. Remove the original bottom rail filler from the bottom of the door panel.
3. Install the new bottom rail filler using the provided fasteners and a Phillips head screwdriver.
4. Reinstall the operating door panel in the frame of the unit by following the steps in the Panel Assembly and Installation Guide.

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