Double Pane Low E Windows U Factor

Generally speaking windows all have a u factor between 1 3 and 2 and the lower the number the better.

Double pane low e windows u factor.

Old metal casement window 1 3. Additionally the window selection tool compares average simulated energy costs for your location based on various window types. This figure illustrates the characteristics of a typical double glazed window with a low solar gain low e glass with argon gas fill. Energy star provides recommended u factors for your climate.

The only exception to this rule are roof and skylight windows with low e smartsun glass which offer a u factor of 0 35. Most windows now carry this rating so it s becoming easy to make comparisons. Low u factors are most important in heating dominated climates although they are also beneficial in cooling dominated climates. 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.

Consult specific manufacturers for nfrc rated u factors and shgcs for products of interest. Fiberglass frames can be either hollow or filled with foam insulation. Good quality single pane window 1 0. Triple glazed windows may have a u factor as low as 0 15.

Gases are heavier than air and therefore provide insulation resistance to air. Double glazed low solar gain low e glass. Window type u factor ratings. Three panes of glass also available on select product lines for increased energy efficiency.

Two panes of glass with sundefense low e protection and insulating argon between the panes. 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 glass is optimal for conserving energy because it reduces ultraviolet uv and infrared light penetration to limit heat transfer. 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.

Fiberglass frames are strong durable low maintenance and provide good insulation. Double paned windows may have a u factor at or below 0 30. Good single pane with storm window 6. Double pane clear and low e.

Some triple pane windows may have a u factor as low as 0 15. Sections may be hollow or filled with foam insulation. The best high performance double pane windows may have a u factor of 0 30 or lower indicating that they are very energy efficient. Vinyl frames are low maintenance and provide good thermal insulation.

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. Double pane with low e. Low e is a microscopically thin and virtually invisible coating that is applied to the side of glass that faces. Blocks 95 of the sun s ultraviolet rays.

A double pane glass is a term to describe the process of adhering two pieces of glass together to create a. Blocks 94 of the sun s ultraviolet rays.