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How to Adjust an Adjustable Sill

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Sometimes doors can become problematic, and having a perfect seal is important, especially when friends and family are inside. Visible light, cold air drafts and even leaky doors are all tell-tale signs that your door sill may need adjusting.

In this project guide, adjusting your sill is made easy with our step-by-step video that teaches you how to adjust your adjustable sill. From removing the cap plugs to testing the cap height, we’ve got you covered. Let’s get started!

Remove any corner pads from the door frame


a. Remove any corner pads from the door frame.
Remove the cap plugs from the cap, if present


a. Place painter's tape around the cap plug. This will help protect the finish of the cap when we remove the plugs.

b. Use the putty knife to pry the cap plugs up and away from the cap.

Adjust the Screws


Tighten or loosen each adjustment screw a small amount to achieve the desired height.

Not sure which way to go?
• If you can see light, or feel air under your door panel, you need to raise your cap by loosening screws.
• If it is difficult to open and close your door panel, you may need to lower your cap by tightening the screws.

Check your adjustment


a. Open and close your door to check the adjustment.

b. Readjust the cap as necessary:
• If the door is too hard to close, you may need to tighten the screws to lower the cap.
• If the door is too easy to close and there is no compression of the door bottom, you may need to loosen the screws to raise the cap slightly.

Reinstall the cap plugs


Place the cap plug over the cap hole and press down firmly. You may use a rubber mallet to secure the plugs.
Reinstall the corner pads


a. Remove the paper backing. Align the bottom of the corner pad flush against the top of the sill cap.

b. Align with weatherstrip and door jamb based on the strike margins (distance between door panel and side frame on the strike side):
• If the margins are less than 5/32`` (tight), align with the weatherstrip kerf.
• If the margins are 5/32`` or greater, align with interior side of door jamb.

c. Press firmly into place.

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