Double Pane Low E Windows U Factor

Double pane dual pane glass naturally performs better than single pane glass for energy efficiency as the space between each pane acts as an additional layer of insulation from the heat or cold.

Double pane low e windows u factor.

Sections may be hollow or filled with foam insulation. Most windows now carry this rating so it s becoming easy to make comparisons. Double pane clear and low e. Generally speaking windows all have a u factor between 1 3 and 2 and the lower the number the better.

Some triple pane windows may have a u factor as low as 0 15. Two panes of glass with sundefense low e protection and insulating argon between the panes. Old metal casement window 1 3. For most energy efficient windows the u factor for the entire window assembly is higher than the u factor at the center of the glass.

Blocks 94 of the sun s ultraviolet rays. High performance double pane windows can have u factors of 0 30 or lower while some triple pane windows can achieve u factors as low as 0 15. Double glazed low solar gain low e glass. Consult specific manufacturers for nfrc rated u factors and shgcs for products of interest.

Blocks 95 of the sun s ultraviolet rays. Good quality single pane window 1 0. Triple glazed windows may have a u factor as low as 0 15. Double paned windows may have a u factor at or below 0 30.

Gases are heavier than air and therefore provide insulation resistance to air. Double pane with low e. The best high performance double pane windows may have a u factor of 0 30 or lower indicating that they are very energy efficient. Good single pane with storm window 6.

Additionally the window selection tool compares average simulated energy costs for your location based on various window types. Fiberglass frames can be either hollow or filled with foam insulation. This figure illustrates the characteristics of a typical double glazed window with a low solar gain low e glass with argon gas fill. Low e smartsun windows and doors feature the best heat insulation of all andersen products with u factors ranging from 0 24 to 0 25.

Energy star provides recommended u factors for your climate. Very hot sunny climates. Low e is a microscopically thin and virtually invisible coating that is applied to the side of glass that faces. Vinyl frames are low maintenance and provide good thermal insulation.

The u factor will approach the very low 0 15 point if there is a gas such as argon or krypton between the layers of glass glazing. Fiberglass frames are strong durable low maintenance and provide good insulation. Low u factors are most important in heating dominated climates although they are also beneficial in cooling dominated climates. The only exception to this rule are roof and skylight windows with low e smartsun glass which offer a u factor of 0 35.

Low e glass is optimal for conserving energy because it reduces ultraviolet uv and infrared light penetration to limit heat transfer. Energy star certified windows come in a variety of framing materials.