How to Open a Stuck Window

Double-hung wood frame windows are prone to sticking open or shut. Unsticking them can be a difficult task unless you know the techniques for opening them without damage to the windows or to yourself. You can unstick a window in just a few minutes once you’ve learned how. If your window keeps getting stuck because of its age or a damage, it may already be time for a window replacement.

LOOKING FOR CAUSE

Windows, especially wood frame windows, can stick for a variety of reasons: humidity, paint, foreign objects. The first step in opening or closing the window is to determine why it is stuck. First, if you have never had the window open, look for nail holes and other signs that indicate that the window might have been nailed shut by a previous owner. All the tugging in the world won’t open a window nailed shut. Check around the casing for nails. If you find them, you may need to remove some wood around the heads in order to get a grasp on them and pull them out.

If there are no nails in the casing or they have been removed, the next step is to make sure that the window is unlocked. Some older latches look open when they are actually latched. Verify an open latch before moving on. If the latch is stuck, you can usually remove it by unscrewing it from the casing. Then try opening the window.

The most common cause of a stuck window is that it was painted shut. You may see continuous paint between the casing and sash indicating that the two have bonded. The best method of breaking this bond is to wedge a putty knife between the casing and the sash around the perimeter, breaking the paint seal. Depending on how the window was painted, you may have to do the same for the exterior seam. Make sure you break the seam between the upper and lower sash.

If the window still doesn’t open, the cause may be more difficult to determine. The next place to check is the window tracks where the sash fits into the casing. Check the tracks for obvious obstructions, like a nail, excessive paint, or a sash cord. Remove the obstruction. If the window isn’t completely stuck but does have difficulty in moving, spray the track with a silicone lubricant and allow this to penetrate cracks. In many cases, the silicone will reduce friction and allow the unit to open and close more easily.

If the cause of sticking is humid air, you may not want to attempt opening the window until the wood dries out. If this isn’t acceptable, consider removing molding, and removing and sanding down the sash and casing for a loose fit. Refer to Doors, Windows & Skylights by Dan Ramsey (TAB BOOKS, 1983) for more complete information on window construction and repairs.

LAST RESORTS

If the above efforts don’t open your stuck window, consider the following methods. First, use a rubber mallet to strike the top cross-member of the lower sash upward. If you don’t have a rubber mallet you can use a block of wood against the sash and strike carefully with a carpenter’s hammer. Make sure all your force is upward, not toward the glass, as the glass can easily break.

Next, strike the top cross-member upward in one corner, then the other in order to break any bonds between the sash and the casing or track. Again, be careful not to break the glass.

If your window is double hung, you may have better luck attempting to open the upper sash. If the upper sash is movable, use the above techniques to loosen and move it.

Finally, try lifting the sash from the outside, if possible, with a pry bar. Once the edge of the bar is under the sash, place a small piece of wood under the bar’s head and use it as a fulcrum to lift the sash.

If all the above methods fail and you still want the window open, call a carpenter. They may have to dismantle some of the window frame, but in most cases they will be able to open it for you and determine why it was stuck in the first place. Watch them work to learn how they accomplish the job. You may someday have to open another stuck window.