Energy-Efficient Window
For a typical house, windows can account for 10% to 30% of the heating and cooling bill. Upgrading from single-pane windows to energy-efficient windows can cut this in half or better, so savings of up to 15% of your current bill are reasonable. Depending on where you live, this can amount to $50 to $100 per year. Spread over 20 years, this means $1,000 to $2,000. You can get a better estimate by running our Home Energy Adviser.
But the big thing to keep in mind is that many of these window replacement firms use simple double-pane windows; for just a little more money up front, you can save a lot of energy over the long haul by asking for windows with special low-e coatings and inert gases, such as argon or krypton, which fill the space between the panes of glass. Some manufacturers even offer ’super windows’ with one or two thin plastic films sandwiched between the panes of glass. These windows can reduce energy loss to one-half as much energy as standard double-pane glass, and one-fourth as much as single-pane glass. In cooling-dominated climates, use windows that reduce solar gains. For the most appropriate window in your climate, purchase windows with the Energy Star label.
Ask the salesperson to tell you the “U-value” of the windows they offer. This is sort of like the miles-per-gallon rating for new cars; an independent agency performs these ratings. In this case, lower is better: the best you can buy today have U-values of around 0.2, while a typical double-pane window is around 0.5.
Note: One thing to keep in mind is that replacing windows is often not justified solely on the basis of energy savings. The cost of replacing windows in existing housing is quite expensive the cost is typically not paid back for 20 to 30 years or more. However, replacing windows will make a substantial difference in the comfort of your home, which could well be worth the cost. Also, double-paned windows typically add to the value and saleability of your home if you put it on the market. In new construction, the labor costs are equivalent regardless of the quality of window installed, so buy the best you can afford.
Over the winter, fog appeared between the panes of your double pane windows, but during the summer it goes away. Why did this occur?
Fog, or condensate, on multiple pane windows is caused by moisture between the glass layers. When it is cold, the moisture condenses on the outer glass pane, very much like water beading up on the outside of a cold glass of water.
There are several reasons why the condensate might have disappeared. One is that your windows might be double-paned, but not sealed. These windows generally have a small air tube connecting the air space between the glazings to the outside. If this tube becomes completely or partially blocked, perhaps by snow or mud, condensation would build up during the colder months. In this case, the blockage could have cleared during the warmer weather. Check for the presence of an airtube in your windows and make sure it is unobstructed. If your double pane windows have been installed for a long time, it is very likely that this is the problem.
If you have sealed windows, like most modern double-pane windows, it is possible that the amount of moisture that leaked into the airspace is very small, small enough to remain in the air as water vapor when the air is warmer. If this is so, you can probably expect it to return next winter.
Another possibility is that the leakage is very large. Once the weather warmed up, the moisture equalized with the outside air, clearing up the fog. Generally, once the seal on a window has leaked, there isn’t much you can do to repair it, and you will probably have to replace the window. In either case, check the warranty on your windows. Most sealed double-paned windows have some form of warranty against leakage. A lot of warranties have a limited life, but some are lifetime.
Source:radiant-heat-floor-methods.com