Double Pane Low E Windows U Factor

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Double pane low e windows u factor.

Very hot sunny climates. 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. Triple glazed windows may have a u factor as low as 0 15. Most windows now carry this rating so it s becoming easy to make comparisons.

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. Blocks 95 of the sun s ultraviolet rays. Fiberglass frames can be either hollow or filled with foam insulation. Two panes of glass with sundefense low e protection and insulating argon between the panes.

Gases are heavier than air and therefore provide insulation resistance to air. Blocks 94 of the sun s ultraviolet rays. Consult specific manufacturers for nfrc rated u factors and shgcs for products of interest. Sections may be hollow or filled with foam insulation.

Three panes of glass also available on select product lines for increased energy efficiency. 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 paned windows may have a u factor at or below 0 30. Double glazed low solar gain low e glass.

Good quality single pane window 1 0. Double pane clear and low e. A double pane glass is a term to describe the process of adhering two pieces of glass together to create a. Additionally the window selection tool compares average simulated energy costs for your location based on various window types.

Energy star certified windows come in a variety of framing materials. Vinyl frames are low maintenance and provide good thermal insulation. This figure illustrates the characteristics of a typical double glazed window with a low solar gain low e glass with argon gas fill. Generally speaking windows all have a u factor between 1 3 and 2 and the lower the number the better.

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. 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. Good single pane with storm window 6. Low e glass is optimal for conserving energy because it reduces ultraviolet uv and infrared light penetration to limit heat transfer.

Some triple pane windows may have a u factor as low as 0 15. Energy star provides recommended u factors for your climate. Low u factors are most important in heating dominated climates although they are also beneficial in cooling dominated climates. Window type u factor ratings.

Double pane with low e. The only exception to this rule are roof and skylight windows with low e smartsun glass which offer a u factor of 0 35.