Repairing Casement Windows

This story shows you how to repair a casement window.


Casement windows are usually made of wood or metal. The sash is attached to the frame with a hinge. A cranking mechanism called an operator attaches, via an arm, to a channel on the underside of the sash. Once the sash is closed, a latch grabs it and tightens it against the frame.

If a casement is difficult to operate, the solution is often as simple as cleaning and lubricating the gears in the operator or the other moving metal parts. If metal parts are broken, they must be replaced.

If the operator and lock work fine but the window is difficult to close, you may need to scrape and sand away caked paint. If bare wood is binding, then the sash should be planed to make it fit correctly.

Finding replacement parts can be difficult. If you can find the make and model of the unit, you may be able to contact the manufacturer or an online parts supply source to obtain the parts you need.

Prestart Checklist

1 or 2 hours for most repairs

Screwdriver, wire brush

Minor mechanical skills

Place a drop cloth on the floor near the window.

Replacement parts as needed, grease or spray lubricant, cloths for cleaning, an old toothbrush

Step 1

Remove the operator arm. To get at the arm, you may need to pry off a wooden stop. The operator arm shown disengages by means of a clip. Other types require you to slide the operator arm along the channel until it reaches the access slot. Then you push the arm down and pull it out.

Step 2

Wire-brush away any rust and clean the arm with mineral spirits or other solvent. Apply lubricant to the joints.

Step 3

Clean the gears with solvent and a toothbrush, then wipe with a rag. Slowly turn the crank to see that the gears mesh. If you see broken parts, replace the operator. Otherwise, apply grease, replace the cover, and test.

Step 4

If the crank assembly still won't work, remove the mounting screws, slide it out, and buy an exact replacement.

Comments (4)
sarahsmithboost wrote:

I want to get some casement windows for my house. Thanks for the advice about how the best way to fix a crank is to lubricate it. Another thing to consider is to get your window installed by a licensed professional.

10/21/2016 03:13:16 PM Report Abuse
sgfsd wrote:

Download over 16,000 WOODWORKING PLANS at here Woodworking guide offers anyone of any skill level the ability to build amazing projects. The guide is extra helpful because it offers more detailed explanations, videos and blueprints then your typical woodworker magazine . Hope it will help you next time !

6/6/2016 09:37:58 PM Report Abuse
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