Sash adjustments may be required to keep a casement window operating smoothly. A properly adjusted casement window sash will have an even reveal, the gap between the window sash and frame, when the window is opened one (1) inch from the side jamb.

Andersen® Casement Window Sash Adjustment Articles

Depending on the casement window Series and operator type, there may be sash adjustment options available. If you need assistance identifying your Andersen® products, visit our Identify Your Product pathway in the Andersen® Window and Door Help Center.

400 Series casement windows have vintage-specific sash adjustments. To verify your casement window vintage, use the Andersen® Glass Code, see Identify Glass Type on Andersen® Windows and Patio Doors. This code contains information to help determine when your product was manufactured.

Sash Adjustments

The following casement window units with the indicated operator type have adjustments available:

A-Series Casement Window

Operator Type: A-Series casement window with split arm operator.

• Operator Types Used on A-Series and 400 Series Casement Windows
• Adjust Sash on Andersen® A-Series Casement Window

400 Series Casement Window

Operator Type: 400 Series casement window with split arm operator from 1998 to November 2006 and November 2006 to Present.

• Operator Types Used on A-Series and 400 Series Casement Windows
• Adjust Sashes on Andersen® 400 Series Casement Windows

100 Series Casement Window

Operator Type: 100 Series casement window with a Dyad operator.

• Operators for 100 Series Casement Windows
• Adjust Sash on Andersen® 100 Series Casement Window

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