Easy Casement Window Adjustment: A Step-by-Step Guide

Updated at: 06/02/2025

Casement windows, with their elegant outward-swinging design, offer excellent ventilation and often enhance a home's curb appeal. However, these beautiful windows can sometimes become difficult to operate, sticking or refusing to latch securely. A poorly functioning casement window can compromise your home's energy efficiency and even impact security. This is especially frustrating when a simple adjustment could solve the problem. Fortunately, many common casement window issues are easily resolved with a few basic tools and a little know-how.

This step-by-step guide will walk you through the process of adjusting your casement windows, helping you restore smooth, effortless operation. Whether your window is sticking, rattling, or failing to latch properly, the following instructions will empower you to tackle the problem yourself, saving you time and the expense of a professional repair. Let's get started!

Safety Guidelines

Always turn off power to any nearby electrical outlets or switches before beginning any adjustments. Electricity and moving parts don't mix!
If you are uncomfortable performing any of these steps, or if the window is significantly damaged, contact a qualified window repair professional.
Use caution when handling any tools, particularly screwdrivers. Avoid excessive force, as you could damage the window frame or mechanism.

Methods: Casement Sash Adjustment using a Sash Wrench

Tools Needed

Sash Wrench (7/16 wrench)
Screwdriver

Step-by-Step Instructions

Prepare the Window
- Remove the screen from the inside of the house.
- Unlock the window and move the casement window out about halfway.
Prepare the Window
Access the Hinge Mechanism
- Use the sash wrench to access the hinge arm on the hinge post.
Adjust the Hinge
- Adjust the hinge arm using the wrench. Moving the wrench right moves the sash right, and moving it left moves the sash left.
- Even out the margin between the casement sash and the frame by adjusting the hinge arm.
Adjust the Hinge
Check and Finalize
- Close the sash and check the reveal. Adjust the top hinge if necessary, as it has the same adjustment mechanism.
Check and Finalize

Tips

If you don't have a sash wrench, you can use a regular screwdriver and a 7/16 open-end wrench to remove the hinge arm, adjust it, and then reattach it.
You might need to adjust the top hinge as well.

Common Mistakes to Avoid

1. Forcing the Window

Reason: Using excessive force when adjusting the window can damage the mechanism or break parts.

Solution: Apply gentle, even pressure while turning the handle or adjusting the locking mechanism.

2. Ignoring Lubrication

Reason: Dry moving parts can cause friction, making adjustment difficult and potentially leading to damage.

Solution: Regularly lubricate the hinges and locking mechanisms with a silicone-based lubricant.

FAQs

My casement window is sticking or hard to open. What should I do?

Sticking windows often need lubrication. Apply a silicone-based lubricant (like silicone spray) to the hinges and latch mechanisms. Work the window open and closed several times to distribute the lubricant. If the problem persists, check for any obstructions like paint buildup or debris.

My casement window is drafty. How can I improve the seal?

Drafts usually indicate a problem with the seal around the window frame or the latch. Inspect the weatherstripping (usually rubber or foam) around the frame for damage or wear. Replace any worn or missing weatherstripping. Ensure the window latch is securely engaged to create a tight seal.