UPVC windows are among some of the most popular types of windows today. They offer good protection against break ins due to their ability to lock with a key from the inside. This prevents a burglar from being able to open the window to either gain entry or to use as means of an escape/exit.
Sometimes you find the windows become misaligned and start to become hard to open or close. If this starts to happen you should get in touch with The Lock Guys immediately to get this fixed before the issue becomes worse and more costly to yourselves.
If for some reason you start to notice you really have to fight with the handles to get them to lock into place after closing the windows, or they just won't lock with the key, you should get this seen to immediately as this creates a huge opening for thieves to enter your property without using any force or making any noise in the process.