This article has installation instructions for corner foam weatherstrip for 400 Series gliding windows. 

400 Series gliding windows use a corner foam weatherstrip. The corner foam weatherstrip is located in all four (4) corners of the window sash frame within the bulb weatherstrip.

Corner Foam Weatherstrip

Corner Foam Weatherstrip

Replacement corner foam weatherstrip is available in universal size and color.

Corner Foam Weatherstrip Replacement Instructions

Tools/Supplies Needed

Safety Glasses

Corner Foam Weatherstrip

Needle Nose Pliers

Mild Soapy Water

Soft, Dry Cloth

Remove the sash, following the guide Active and Passive Sash Replacement for 400 Series Gliding Windows (0004368).

Using needle nose pliers, remove the original corner foam weatherstrip.

Clean the sash corners with mild soapy water and a soft, dry cloth to remove any dirt or debris.

Using a 3" length of foam weatherstrip, gently insert half of the foam weatherstrip into the hollow opening of the rail, leaving the other half sticking out.

Using the other half of the foam weatherstrip that is sticking out, tuck it into the stile bulb weatherstrip, creating a beefy seal around the corner.

Repeat for each corner and reinstall the sash.

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