Single-Hung Window Energy Efficiency
October 11, 2010
Single-hung windows offer natural energy efficiency due to the fact that only one of the sashes opens, while the other remains fixed. While single-hung windows are less common today, they are still available as new windows and as replacements, and they offer the advantage of generally being cheaper than double-hung or casement windows. The efficiency of single-hung windows is important to consider when making your purchase.
The energy-efficiency rating of a window is based on three different factors, regardless of the style of window. The first consideration is non-solar heat loss and gain; anything that heats or causes your home to lose heat, including conduction, convection, and radiation, falls into this category. Then there is the obvious impact of the sun on your windows and home and the related solar heat gains. Finally, airflow is looked at; opening your window is one thing, but if your window lets airflow in and out due to bad installation or design, or maybe loose, damaged seals, this can send your energy bills skyward.
Single-hung windows can be found with double-paned glass, which increases the energy efficiency along with helping keep outside sounds from coming inside. You should also look for single-hung windows that are coated or glazed to maximize the climate you live in; you can find high solar gain glazing to help retain more of the sun's heat if you live in a cold area, or buy windows with a reflective coating to repel the sun if you live in a warm climate. Whatever features your single-hung windows have, energy efficiency can be improved by having them professionally installed.