When you look outside on a sunny day, you’re
seeing the visible part of the light spectrum.
The rest of the light is invisible and it could be
making your bill higher than it needs to be.
Low-e coatings are microscopically thin layers
of metallic oxide bonded to the surface of the
glass in windows. The coatings prevent heat and ultra-
violet (UV) rays from passing through glass. It works
like an invisible mirror reflecting select portions of the light
spectrum back in or out of the windows. Soft, hard, and Heat
Mirror are three major types of coatings on the market. Soft
coat is not durable enough to be exposed to the elements, so
it is applied to the inner surfaces of windows. Hard coat is
resilient enough to be used on exterior surfaces but it is not
quite as energy efficient as soft coat. Hard coat is found
primarily on storm windows and removable energy panels.
Heat Mirror is applied to a thin polyester sheet suspended
between the two panes of a dual pane window. The coating
reflects radiant heat while the sheet decreases heat loss by
splitting the air space in two.