Waterfed window cleaning is a process that uses pure water with zero impurities in it to rinse off the glass. This is done by pumping the water up to a height of around 70 feet, and then using a specialized nozzle to spray it onto the windows. This method is used because it produces the cleanest and streak-free results possible, and it’s also very environmentally friendly since no chemicals or detergents are used. However, it’s also more expensive than other methods, so not many businesses offer this service. *Thanks to SimPole Water-fed Poles for giving us this great information!