Andersen® 400 Series Perma-Shield® casement and awning windows manufactured from 1978 to 2019 have a bulb-style weatherstrip on all four (4) sides of the window sash.

Install Bulb-Style Weatherstrip on Andersen® 400 Series Perma-Shield® Casement or Awning Window

This article provides you with resources for ordering and installing a replacement bulb-style weatherstrip on a 400 Series Perma-Shield® casement or awning window.

Note: For assistance with products manufactured before 1978, Contact Andersen® Windows and Doors.

Safety Warning

Tools and Supplies Needed

• One (1) soft cleaning cloth
• Mild soapy water
• Safety glasses
• Phillips screwdriver
• Flat blade screwdriver

Let's Get Started

1. Order Parts

You can purchase a replacement gray bulb-style weatherstrip or white bulb-style weatherstrip online from the Andersen Parts Store to match your existing weatherstrip.

When doing so, you can order two pieces as a pair for only the vertical or horizontal parts of your window, but we recommend replacing all four (4) pieces at once.

The weatherstrip size is based on the size of your casement or awning window.

Note: You can also now also use a one-piece continuous weatherstrip to replace all previous Andersen weatherstripping. Instead of replacing all four (4) individual pieces, you can use one (1) piece for the entire sash. See Continuous One-Piece Weatherstrip for 400 Series Casement and Awning Windows for more information.

2. Install Parts

To install the replacement bulb-style weatherstrip, follow the written instructions or the YouTube video (for casement windows only) below.

To replace the weatherstrip, you will need to remove the entire window sash first.

• For casement window instructions, see Casement Window Replacement Sash Installation.
• For awning window instructions, see Awning Window Replacement Sash Installation.

Once the window sash is removed from the frame:

1. Remove the existing weatherstrip from the window sash's channel.
2. Clean the channel with mild soapy water and a soft cleaning cloth to remove any dirt or debris.
3. Firmly press the new weatherstrip into the channel one at a time. No adhesive is necessary.
4. Reinstall the casement or awning window sash following the same instructions you used to remove it.

Replacing the Weatherstrip on 400 Series Casement Windows

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