Casement Window Repair: Window Lock

  • 1-2 hours
  • Beginner
  • 10-20
What You'll Need
Household oil (as needed)
Small wire brush (as needed)
Cloth or rag
New fastener set (as needed)

Casement windows repair is necessary at one time or another. They are commonly in older buildings although they can be a nice replacement or addition to any building. The windows are locked with mechanisms called fasteners or latches. It is a simple process to fix the lock if it sticks or fails to lock property. The typical lock is a metal clasp which pivots and slides into a stationary metal fitting, creating a lock to keep the window closed. One side will be affixed to the inside window frame and one side will be affixed to the window sash.

There are different configurations of latching mechanisms, some close on the side of the window and some on the bottom of the window. These clasps can become rusted, break with age, or begin sticking due to dirt or grime. On a wooden window, you may have a lock which no longer aligns. Below you will find a step by step method to repair a casement window lock.

Step 1 – Determine the Problem

You first need to determine what the problem is with the locking mechanism. If it is broken you will need to replace it completely rather than try to repair it. If it is stuck or dirty you can clean it. If it is rusted, you can also try to clean it. Depending upon the severity, this fix may not work and you may have to replace the fastener unit.

In the case with a wooden window where the lock no longer aligns, you can either move the lock so that it can now line up or you can replace the warped part of the window. The latter is preferred.

Step 2 – Clean the Fastener

Begin by inspecting the fastener and see if there are any visible obstructions keeping it from working. Spray a small about of oil into the mechanism, keeping a rag handy for any over-spray or drips. Try to move the clasp back and forth and see if loosens up the movement. Repeat this procedure a few times. With a little bit of work, you may have just fixed your problem.

If there is a rust problem, use a small wire brush with some old and gently scrape at the rust. If there is only a small amount you may be able to remove it and use the clasp again. Again, move the clasp back and forth and try to loosen it up. You can also try using a rust removing solvent. You will need to oil it after using a solvent.

Step 3 – Replace the Fastener

If your lock is broken or rusted beyond repair, you need to replace it with a new one. It is best to buy one with the same size and shape. Remove the old clasp by removing the screws and simply screw in the new clasp in the same place that the old one came out