If your car has to be parked outside overnight, & there’s a layer of ice on the windscreen in the morning, don’t use hot water to get rid of the ice. Hot water will guarantee that you damage the windscreen, especially if you have cracks/chips which will only increase in size if in contact with hot water. (Small cracks or chips in a windscreen are sensitive to sudden heat changes and a can quickly increase in size if they are subjected to a sudden change of temperature).
Rather use a scraper, an old bank card or a plastic knife, remove the ice. Use the air conditioner to demist the interior of the windscreen. When driving in cold conditions don’t use your windscreen sprayers, coz the water from the reservoir will freeze onto the windscreen and the wipers will not be able to clear it from the windscreen.
Also, check the condition of your windscreen wiper blades and replace them even if they’re cleaning the glass but are a little streaky. Wiper blades must be in good condition and need to be inspected regularly, only the edge of the wiper blade should make contact with the windscreen and not the entire rubber body of the wiper blade.
As the driver, you need to be able to see clearly out of the windscreen at all times, so take care and drive safely!