How to Open a Sash Lock Window

How to Open a Sash Lock Window
Published: Sep 20, 2010
Updated: Nov 20, 2021
2 minute read

However, when the temperature or humidity changes, sashes may become jammed and not open. Wood sashes are especially problematic, because wood expands and contracts, causing the window to become stuck in its tracks. Sashes also can become stuck because they were painted shut. If the window frame and sashes become warped because of house settling, you may need a new window.

Things You Will Need

  • Sharp utility knife
  • Hammer
  • Putty knife
  • Pry bar
  • Block of wood
  • Fine-grain sandpaper
  • Paraffin or beeswax

Opening a Sash Lock Window

  1. Place your hands in the middle of the window where the top of the sash is located. This is usually made of wood.

  2. Press upward with your palms on the sash to free the bottom of the window from the windowsill. Push upward enough to give room for a hand to be slipped between the windowsill and the freed sash.

  3. Place both hands underneath the freed sash, and push up the window.

Opening a Stuck Sash Lock Window

  1. If you believe the window was painted shut, use a sharp utility knife to score the groove between the frame and sash. If the window still will not open, proceed to the next step.

  2. Wedge the blade of a putty knife between the sash and the frame. Tap the end of the knife lightly with a hammer. Repeat around the window between the sash and frame. If the window still will not open, proceed to the next step.

  3. Go to the outside of the window, and carefully wedge a pry bar under the sill along the corner of the window. Tap the end of the pry bar with a hammer. Lay a block of wood under the pry bar to prevent scratching the windowsill, and use leverage to lift the window. Repeat for the length of the sill.

  4. Once the window is open, sand any rough areas of the track with fine-grit sandpaper. Rub paraffin or beeswax onto the tracks to help the window from sticking again.

The Drip Cap

  • Window sashes work by moving up and down on tracks.
  • If the window still will not open, proceed to the next step.
  • Wedge the blade of a putty knife between the sash and the frame.
  • Lay a block of wood under the pry bar to prevent scratching the windowsill, and use leverage to lift the window.

Photo Credits

old house window image by Kathy Burns from Fotolia.com

old house window image by Kathy Burns from Fotolia.com

Rachelle Proulx

Rachelle Proulx has been writing since 2000. She co-owns a pet-sitting company, providing her the experience to cover pet care and small business. Proulx is also a flooring specialist who writes about flooring options, preparation,…

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