Window glass thickness dating technique
Sorting through the options takes a bit of effort, but it more than pays off in increased comfort and reduced energy costs.
Single-Pane Windows with just one layer of glass suck energy dollars from a house and offer little protection against heat or cold.
You can also go to and download a program called Resfen.
The software, which is free (PC-compatible only), lets you calculate how windows with different glazing systems and frame materials will affect your energy bill.
The label shows how the window performs in three key areas.
If puzzling through the label is daunting, the EPA's Energy Star program makes judging efficiency easier.
That means that depending on the type of fuel used in a home, low-E windows can pay for themselves in 5 to 10 years.
It's possible to buy dual-pane glass without a low-E coating, but Tom Silva doesn't recommend it.
Superglass, the most expensive glazing system on the market and one of the best insulators, suspends two layers of Heat Mirror between panes of glass with gas-filled spacers.
Double-Pane Insulated Glass Most new windows sold today are dual-pane glass (sometimes called insulated glass or by the formerly trademarked name Thermopane), in which a layer of inert gas — typically argon or krypton — is sealed between inner and outer panes.
The gas is a poor thermal conductor, so it slows the passage of heat through the glass, eliminating the need for storm windows.
That explains why few new single-panes are sold today.
If you opt for single-pane windows because of their traditional look, choose ones in well-made wood frames, and combine them with snug-fitting storm panels to boost their energy efficiency.
Search for window glass thickness dating technique:
Low-E and Heat Mirror Glass Adding panes and gas-filled spacers is one way to get a more efficient window.