Q - Where are your window cleaning rounds? A - To see where we cover please click HERE. Q - How often do you clean the windows? A - We recommend cleaning external windows every 4 weeks to stop too much dirt build up. Q - Do you clean window frames, doors and sills? A - Yes we do unlike other window cleaners, this is all included in the quoted price. Q - What is pure water? A - Tap water contains many different impurities. Pure water contains no impurities or chemicals. after it has been purified by our reverse osmosis and DI processes, Pure Water acts as an outstanding cleaning agent, by going back to its impure state.