400 Series Perma-Shield® casement and awning windows from 1978 - 2019 have a bulb-style weatherstrip as a replacement. This weatherstrip is located on all four (4) sides of the window sash. If updating to the bulb-style weatherstrip, all four (4) pieces need to be replaced.

Replace Bulb Style Weatherstrip for 400 Series Perma-Shield® Awning and Casement Windows (1978-2019) 

There is now a one-piece continuous weatherstrip that can be used as a replacement for all previous weatherstrip vintages. Instead of replacing all four (4) pieces, one (1) piece can be used as a replacement for the entire sash. See Continuous One-Piece Weatherstrip for 400 Series Casement and Awning Windows.

Please Contact Andersen® Windows and Doors for assistance with products manufactured prior to 1978.

Replacement Parts

Order bulb-style weatherstrip as a pair for the vertical or horizontal pieces. Sizing is based on the awning window size or casement window size. It is recommended to replace all four (4) pieces at once.

Gray Bulb Weatherstrip  / White Bulb Weatherstrip

Installation

Replacing the Weatherstrip on 400 Series Casement Windows

Tools/Supplies Needed

• Safety Glasses
• Flat Blade Screwdriver
• Philips Screwdriver
• Replacement Weatherstrip
• Mild Soapy Water
• Soft, Dry Cloth

Safety Warnings

Install Replacement Weatherstrip

To replace the weatherstrip, the sash must be removed first.

• For casement sash, refer to the guide: Casement Window Replacement Sash Installation
• For awning sash, refer to: Awning Window Replacement Sash Installation

1. Remove the existing weatherstrip from the window sash.
2. Clean the channel with mild soapy water and a soft, dry 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. Install the casement sash following the instructions.

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