Because windows are the last line of defense against water damage, one must consider material and invest in professional window installation for optimal energy savings.
The majority of windows that are in use today function by sliding their sashes past one another, while windows that close by pressing against the frame have lower air leakage and higher energy efficiency. In order to improve performance, more window panes create an insulated air space that impedes the transfer of heat and sound. For hot, sunny climates, window coverings can lessen solar heat gain and boost energy efficiency.
Informed window selection can result in savings because poor insulation causes expensive energy loss. In fact, the average 1,700–2,600 square foot home in the United States loses hundreds of dollars per year merely by not changing its windows. Additionally, spaces surrounding the windows allow up to 30% of the warm or cooled air in a house to escape. As one can see, one can save time and money making the best window selection.
Source: windownation.com