How to Easily Adjust a Door Gap Using Cardboard Shims

Updated at: 09/05/2025

Dealing with a drafty door? A gap at the bottom letting in unwanted noise or pests? Don't despair! A simple and inexpensive solution often lies within reach – literally. Cardboard shims, readily available from almost any home or easily crafted from spare cardboard boxes, offer a surprisingly effective way to adjust door gaps and restore a proper seal. This readily accessible material provides a temporary fix or a surprisingly durable solution depending on your needs and the size of the gap.

Forget expensive weatherstripping or complicated carpentry; this quick and easy method utilizes materials you probably already have. In the following steps, we’ll guide you through the process of accurately measuring your door gap and precisely applying cardboard shims to achieve a perfect fit, eliminating drafts and restoring peace and quiet to your home.

Preparation and Safety Guidelines

Tools Needed
  • Cardboard (from hinge packaging)
  • Screwdriver
Safety Guidelines
  • Always ensure the door is properly secured and won't swing unexpectedly before starting. Use a door stop or have someone hold it.
  • Avoid using excessively thick cardboard shims; this can damage the door frame or cause the door to bind and become difficult to open or close.
  • If the gap is significant, or you're uncomfortable with this DIY fix, consult a professional carpenter or handyman.

Step-by-Step Instructions

  1. Prepare the Door and Hinges

    • Open the door fully to expose the hinge leaves.
    • Loosen all screws on each hinge. The screws closest to the door jamb need only slight loosening (1/8 inch), while the others need more (1/4 inch).
    Loosen all screws on each hinge. The screws closest to the door jamb need only slight loosening (1/8 inch), while the others need more (1/4 inch).
    Prepare the Door and Hinges

  2. Prepare the Cardboard Shims

    • Cut thin pieces of cardboard (approximately 3/8 to 1/2 inch wide) to fit behind the hinge leaves. If using multiple layers, fold them together to achieve desired thickness.
    Cut thin pieces of cardboard (approximately 3/8 to 1/2 inch wide) to fit behind the hinge leaves. If using multiple layers, fold them together to achieve desired thickness.
    Prepare the Cardboard Shims

  3. Insert the Shims

    • Close the door as much as possible. The hinges will bind on the screws, but this allows you to insert the shims.
    • Insert the cardboard shims behind the hinge leaves, ensuring they're flush with or slightly behind the edge of the door jamb. Avoid placing them too far back.
    Insert the cardboard shims behind the hinge leaves, ensuring they're flush with or slightly behind the edge of the door jamb. Avoid placing them too far back.Insert the cardboard shims behind the hinge leaves, ensuring they're flush with or slightly behind the edge of the door jamb. Avoid placing them too far back.
    Insert the Shims

  4. Secure and Check

    • Tighten all the screws on the hinges.
    • Check the door gap. If needed, adjust shims and repeat steps 5 and 6.

Read more: 3M Thinsulate Window Film Installation: A Step-by-Step Guide

Tips

  • Use cardboard from the hinge packaging for easy and inexpensive shims. It's thin enough not to interfere with the screws.
  • You may only need to adjust one hinge at a time, depending on the unevenness of your gap.
  • The shims help pivot the hinge and shift the door. This adjusts the door gap.

Common Mistakes to Avoid

1. Using Cardboard That's Too Thin or Weak

Reason: Thin cardboard can compress under pressure, leading to an uneven gap and a poorly fitting door.
Solution: Use thicker, more rigid cardboard or multiple layers of thinner cardboard for added strength.

2. Not Properly Securing the Shims

Reason: Loose shims can shift, resulting in an inconsistent gap and potential damage to the door or frame.
Solution: Use adhesive or small nails or screws to securely attach the cardboard shims in place.

3. Ignoring the Hinge Adjustment

Reason: Relying solely on shims when the door hinges are misaligned can create unnecessary stress and an imperfect fit.
Solution: Adjust the door hinges first before using shims to achieve optimal alignment and a uniform gap.

FAQs

How long will cardboard shims last?
The lifespan depends on the quality of cardboard and the amount of wear and tear. Thicker cardboard will last longer. Expect several months to a year in most cases, especially in areas with moderate use. You may need to replace them sooner if the door sees heavy traffic or significant moisture.
Will cardboard shims damage my door or frame?
Cardboard shims, when properly installed, shouldn't damage your door or frame. Avoid using excessive force; gently wedge them in place. If you're concerned, consider using a soft material like felt or foam tape under the cardboard for extra protection.