If you're noticing that it is difficult to open and close your windows and that you have to use excessive force to do so it suggests that there may be an issue with the window hinge. Hinges tend to cause most window problems as dirt and grit can build up on them over time.
It may be that your window hinges have just become a little stiff and will need some lubrication so that they can move more smoothly.We recommend that you lubricate all of the windows moving parts at least once a year to reduce wear and tear and prevent damage. Remember to take care when applying the substance to avoid any damage and leaks on your furnishings.
To lubricate your window use a silicone spray and a cloth to avoid getting oil in unintended areas. Open your window to expose the hinges and locking mechanism. Insert the nozzle of the can into the locking mechanism and spray two to three times and spray the external moving parts. Turn the handle to work the spray in. Wipe away any excess drips. Oil the hinges and hinge guide rail from top to bottom on both sides. Open and close the window to distribute the silicone spray.