We had Simonton vinyl put in several months ago and like the look for our house, as well as the results. Since we jsut mvoed in, we have no real comparison for our bills, but we ran the a/c at 77 or 78 most of the (quite hot) summer here and our bills were no more than $80/month. The next door neighbor with an identical house (about 6 ina row are nearly carbon copies, built in late 50s), has original aluminum windows and said she liked to keep the temps at 74/75, and her bills were in the $300 range. There may well be some other lifestyle factors involved but her kid is not a toddler yet so he wouldn't be running in and out all the time.

We also know from teh brief period of living her in late winter before we replaced the windows that when the wind blew, the curtains moved. Noticeably! And you couldn't sit near the picture window unless you were well bundled. Now we have lots of wind and the house feels snug.

We had them installed in May, I think, so I can't tell you how they last over the years. But I'm happy.

Robin

We have had Alside Excalibur windows in our home since August (live in Maryland) and I have to admit they aren't all they advertise they are. We have found through the winter a great deal of cold air leakage. I would look elsewhere.

I ended up having custom all wood windows made in a local shop, but my architect had recommended Marvin windows if I wanted to go with manufactured units. He said he uses Marvin in many of his projects, which all tend to be very high end.

I trust my architect, so his recommendation would lead me to believe that Marvin is making a very high-quality product.

Alsides has a another model you might look at, Sheffield. Only slightly higher priced.

My experience is that the installation is more important than the actual window when comparing the vinyl windows such as Alsides and Simonton. They all carry similar warranties and have similar construction in their higher end models.

The Marvin Infinity is imho a much better window than any of the vinyls. If installed correctly there should not be any problem.

To Robin G: I would call the contractor that installed those windows and have them either replace them or fix the bad installation. Or, call Alsides directly and have them come check it out.

I have many clients who have purchased Alsides windows and none have complained about leakage. We did have a problem once when 3 of 21 windows were badly scratched during shipment. Alsides had a rep onsite within 2 hours of my notifying them. Their solution: They offered the client a complete replacement of all 21 if they couldn't repair the cosmetic scratches to the home owners satisfaction.

Still, if the price differential isn't an issue, the Marvin's are a better window.

I'm real happy with Andersen 440 model windows.

Regarding " I believe an R value below .35, low E glass and argon are obvious choices, so at this point," you need to reevaluate your selections.

You want a high R-value & a low U-value. The U-value is equal to 1/R. No window manufacturer makes a window w/ a R value = to .35.

Most people are much more familiar with R-values, which are used to rate how well a material such as insulation resists the flow of heat through it. The higher an R-value is, the more heat loss it resists, and therefore the more energy efficient it is. U-values differ from R-values in two important ways, and when you're shopping for energy-efficient components for your house, it helps to understand the difference.

First of all, where the R-value is used to rate the energy efficiency of a single component - a batt of insulation for example - U-values rate the energy efficiency of the combined materials in a building component or section. For example, in a typical insulated window you have the two panes of glass, the dead air between the glass, the frame material and perhaps some weatherstripping or sealants that hold everything together. Because each of these components works together as a unit, the U-value is used to indicate the energy efficiency of this entire assembly.

The second distinction is that U-values rate how much heat is conducted through this combination of materials. So, where R-values rate how much heat loss the material resists from passing through it, U-values rate how much the heat the component allows to pass through it. Therefore, while a high R-value indicates good energy efficiency - R-19 is better than R-11, for example - while a low U-value indicates good energy efficiency - U-0.35 would be better than U-0.43.

I've installed a variety of windows from local millener's models to national brands such as Marvin, Anderson, ALside and some of the lower end contractor grade offerings from lumber yards. I agree with the commenter who said that installation makes the difference. Proper flashing and sealing makes all the difference, which is the responsibility of the installer. Also, every manufacturer has different grades that they offer, so I'd suggest asking about their different lines and making a comparison. Also consider service, service, service.

In my experience, Marvin and Alside windows and local milleners usually have very good service after the sale, which the larger big box stores aren't so good about.

.35 u value, low-e and thermal pane are pretty standard in the industry. Some manufacturers offer a triple pane window as well.