Occasionally, you may have to deal with sticking windows at home. Various factors may cause a window to get stuck. A buildup of dirt and debris in the window casing can hinder normal operation. Problems in the foundation of your home can cause windows to lose alignment and get stuck. Sometimes, a window is painted and shut before it completely dries. This effectively glues the window closed. High humidity can cause doors and windows to swell and bind them in the jamb. Whatever the case, it helps if you know how to free a stuck window.
Identify Paint Bonds
Windows that have been painted over are the most common causes of stuck windows. It is usually easy to spot the paint seal on a stuck window. However, if you’re unable to see the seal, you need to determine where the bond is. Insert a piece of paper, the thin blade of a flexible putty knife, or the flex blade of an Olfa utility knife (Fig. 1) between the window casing and the perimeter of the window sash. Slide the paper or tool all around the sash. When it can't move through the gap, take note of this as a stuck point. Use a utility knife to cut through the paint bond.
Cut Through the Bond
A few tools will be required to unstick a window sash, some specialized for that purpose. A utility knife, scraper, window zipper (designed to cut through paint or other material binding window sashes) (Fig 2), or the double-ended window tool (Fig. 3) would be the best ones.
Firmly press the tool blade into the seam. Your objective is to cut through the bond between the window sash and the casing (Fig. 4 & Fig. 5). Trace the knife through the bond, back and forth. You may have to trace several times before the bond finally gives way. Attempt to open the window. If it doesn’t open, go outside and look for a bond in the same manner.
Hammer and Block of Wood
You could also try and free the window with a hammer and wooden block. Work from the inside of the window. Hold a small block of wood against the window sash. Strike the wood gently with a hammer. Be careful to direct the pressure outwards from the sash and not inwards towards the glass. This will help to prevent the breakage of the glass. You also want to be sure not to damage the woodwork. Move the wood along the sash so that you’re able to tap all around. The pressure from the hammer should loosen the stuck window and enable you to open it.
Lubricating the Window Channels
Spray-on silicone lubricant is probably one of the best solutions to keep window channels sliding smoothly. Rubbing wax or a block of Paraffin on the window channels is often the go-to solution, but it could cause a buildup that would make windows even more difficult to operate down the road. Silicone spray is available at most hardware stores.
If you should choose to opt for a quick fix using wax or paraffin, however, rub the wax of a candle or a block of paraffin along the sash channels with the sash open. It will help to lubricate the window to let the sash operate. You should then be able to slide the window up and down, so open and shut the window a few times to make sure it is functional.
Unscrew the Latch
A faulty latch (Fig. 6) may cause a window to get stuck. The latch may appear to be open when, in actual fact, it is stuck. This prevents the window from any movement. If you’ve pried all around the window frame and it still doesn’t open, try the latch. Use a screwdriver to remove screws from the casing. Once you’ve removed the latch, you should be able to open the window. Make arrangements to replace the latch.