Make sure it is a window that is meant to be opened. Some new office and home windows are not meant to be opened. If there are no hinges or the window is a single pane with nowhere to slide, it likely does not open. Make sure that the window is not nailed or screwed shut for security or energy conservation reasons. Check for any staples around the interior of the window where plastic sheeting may have been fastened. Carefully remove them with needle-nose pliers. Make sure any locks are disengaged. Look to see if the window frame has been recently painted. Decide which direction the window is supposed to open: up, outward or sideways.
Use a razor knife to cut along the edge of the window and the frame. Cut across all four sides of the window. You may need to check the exterior of the window in addition to the inside to make sure that it isn’t painted shut on both sides.
Push each corner to see if there is any movement. Press on the window gently to open it a little at a time.
Reposition the pry bar along the bottom edge of the window to lift both sides of the window. Using a pry bar may damage the wood of the window or window frame, use this method very carefully as a last resort.
Run a hair dryer along the edges of the window frame for several minutes. After drying the wood, try opening the window. Place a dehumidifier in a room with stuck windows. Lowering the humidity in the room should help reduce the swelling of the window frames.
If the window opens outward on hinges, spray the hinges with the lubricant for smoother operation.
Window frames with severe water damage may need to be replaced entirely.
Use a utility knife to remove any paint that is sealing the stop to the window frame. Remove any screws that are holding the sash in place. Gently pry the stop out using a flathead screwdriver or paint scraper. Be careful when removing the stops as they can snap easily. You may need to purchase a replacement stop to reinstall the window.
Remove the rope from one side of the window by pulling the knot down and out from the side of the window sash. Remove the other rope from the other side in the same manner.
Use a hand planer on the sides of the window if your sash has swelled.
Use a razor knife to cut around the edges of the window inside and outside. Slide the upper sash down to reveal the pulleys in the side of the window jamb. Pull the right side of the window in to free it from the jamb. Remove the rope connecting the sash to the pulley inside the window frame and jamb. Pull the left side of the window out and remove the rope.
Attach the ropes to the upper sash and slip it in place one side at a time. Attach the ropes to the lower sash and place the bottom half in first. Push the upper half in place. Slide the window stop back in place and attach it with screws or finish nails.
