What's best for Milwaukee Weather? There are two types of Low E Coatings. The one we use is a soft coated Low E. It is silver sandwiched between layers of metal oxide in a vacuum chamber. The advantages to soft coat Low E are that it offers a high visible light transmission, ultra-low emissivity which gain optimum u-values for our cold Milwaukee winters, and up to 70% less UV transmission compared to standard clear glazing. The disadvantages of a soft coat are that it is so fragile that it requires two coats and needs extreme care when handling it. It is more expensive for this reason and it also doesn't allow as many accessories as a hard coat because blinds in-between the panes are not an option. Hard Coat Low E is applied at a very high temperature and is sprayed onto the glass surface. The advantage to hard coat is that it can be tempered after the coating application and it offers to accessorize with the glass such as blinds in-between the panes. The disadvantages of a hard coat Low E is that the u-values are going to be higher so the window isn't going to be as energy efficient. It also will have a higher solar heat gain coefficient which means more light will be able to pass through keeping cooling bills high in summer.