Inswing Sill Extender

A sill extender allows a common sill size to be extended to create a larger sill. This is necessary when the jamb size is not the typical width. Most sills are the same length as the jamb is deep. When there is a deeper jamb, the sill will stop short. Adding a sill extender makes the door unit look more correct.

Inswing sill extenders are an aluminum sill nosing that increases the width of the sill. It slides or snaps onto the front portion of a 5-3/4″ sill allowing for different jamb widths. Sill extenders can also be used to create a sill horn. A sill horn is where the jamb leg comes to the side of the sill and the brickmould or casing comes down on the nosing of the sill.


1″ Sill Extender

A 1″ sill extender will be used with a 5-3/4″ sill. This extender is available in 3′, 6′, and 13′ lengths and is available in a mill, bronze, or nickel finish to match the finish of the sill.


1-3/8″ Sill Extender

A 1-3/8″ sill extender will be used to create a sill horn with a 4-9/16″ jamb depth. This extender is available in 3′, 6′, and 13′ lengths and is available in a mill, bronze, or nickel finish to match the finish of the sill.


2″ Sill Extender

A 2″ sill extender will be used with a 5-3/4″ sill. This extender is available in 3′, 6′, and 13′ lengths and is available in a mill, bronze, or nickel finish to match the finish of the sill.


3-1/4″ Sill Extender

A 3-1/4″ sill extender will be used with a 5-3/4″ sill. This extender is available in 3′, 6′, and 13′ lengths and is available in a mill, bronze, or nickel finish to match the finish of the sill.


Updated on May 15, 2021

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