Frequently Asked Window QuestionsHow often should residential windows be replaced?

Homeowners with windows over 25 years old should consider replacing them, both to gain the best energy efficiencies and to protect the “envelope” of the house. A home is an ideal candidate for a window replacement if its windows are sealed or painted shut, experiences ice buildup or a frosty glaze during the winter, gets fogged with condensation or has drafts that come through the windows. Do replacement windows really pay for themselves or is that just a sales line?

It’s true, if you select high-quality, energy-efficient windows. Savings will vary, but expertly engineered and well-built windows lower home energy consumption. With vinyl-framed windows, maintenance is also virtually eliminated. No need to scrape and paint windows.

These energy and maintenance savings will allow you to recoup your window investment over time. Will new windows eliminate condensation?

Actually, no. Condensation is moisture vapor suspended in the air, and that’s something no one can guarantee to eliminate. However, high-quality vinyl windows incorporating warm-edge technology glazing systems will help to reduce condensation because they’re much less thermally conductive than other window types. They can help keep the temperature of the window warmer—minimizing the hot and cold differences that turn moisture into condensation. What makes a window or door energy efficient?

Numerous factors, including how the frame and sashes are engineered and built, the type of glass used (single-, double- or triple-pane), the weather-stripping, the type of low-emissivity coating on the glass and the presence of argon or krypton gas. What is ENERGY STAR®—and what does it have to do with windows and doors?

ENERGY STAR is a U. S. government program—administered by the Department of Energy and the Environmental Protection Agency with the cooperation of manufacturers—that’s designed to reduce the consumption of fossil fuels through the education of consumers. The program covers many different types of products. Windows and doors can only carry the ENERGY STAR label if they are tested by an independent laboratory through the NFRC program and meet specific, predetermined U-value ratings. By selecting ENERGY STAR products, you will reduce your energy costs and help make the environment cleaner. What is the NFRC and what should I know about it?

NFRC stands for the National Fenestration Rating Council. It’s a program established by the U. S. Department of Energy to help consumers compare window products and options. Window manufacturers participating in the program are required to label every window to its specific thermal performance level. Customers are then ensured that the products they select meet the requirements for their application. Participation in the NFRC program is voluntary. Not all manufacturers participate because it requires outside third party inspection and extensive product testing. What does Low E stand for?

Low E is a non-visible, microscopic layer of silver coating added to glass for greater energy efficiency and increased comfort. Low E stands for “low emissivity”, which is the action of reflecting light passing through glass. By reflecting part of the light spectrum (the part that transmits heat), we reduce a window’s U-Value and increase its R-Value. What do U-values and R-values really mean?

U-Values represent the amount of heat that escapes through a wall, window, roof or other surface. The lower the U-Value, the more energy efficient a material is. R-Values are the direct opposite. These measure an object’s resistance to heat flow. The higher a material’s R-Value, the lower its U-Value, and the less energy it will lose. An R-Value depends on the number of layers of glass in a window, what type of gas is between those layers, and whether one or more of those layers of glazing have been treated with a Low E coating. Can windows keep out UV radiation that fades carpeting, furniture, draperies and upholstery?

Using a low-emissivity glass in your new windows or doors will filter more than 50 percent of the damaging UV light. The absolute most effective glass for this purpose, however, is laminated insulating glass. It features a polyvinyl butyral inner layer and a low-emissivity coating that filters more than 99 percent of UV radiation that fades interior furnishings. Can windows and doors reduce outside noise?

All windows and doors reduce noise to some degree. The best solution, however, is to use a laminated, insulating glass system in windows and doors. It provides as much as a 100 percent improvement in sound deadening over other glass types. What are some common styles of windows on the market today?

Depending on region and personal style, single-hung, double hung, casement, awning, slide-by, bay and bow windows are the most frequently used. A number of other style windows are frequently employed as accent windows. What is an awning window?

An awning window is hinged at the top and swings out at the bottom to open, operated by a cranking mechanism. What is a bay window?

A bay window is a series of usually three windows assembled in a polygon shape that projects outward from the side of a house. How does this differ from a bow window?

Bow windows are very similar to bays, in that they also project from the side of a house. However, they are usually

composed of a series of five window units assembled in an arc, rather than a polygon. What is a casement window?

A casement window is a window unit hinged at the side that swings outward, operated by a cranking mechanism. What is a gas-filled window?

Modern window technology permits an inert gas, usually argon, to be sealed between the panes of glass in a window instead of air. The gas is a far better insulator that just air, thus further increasing the thermal value of a window. What is insulated glass?

Technically, there are two or more panes of glass separated by insulation at the edges and air in the center to provide greater thermal efficiency to a window. How do I know what type of glazing is right for a window?

Different climates and styles of homes require different glazing options to maximize their energy efficiency. Some glazing options can also help reduce outdoor traffic noise from entering the home. Options range from single glazed glass, as in historic homes (minimal insulating value), up to R10, which features dual-sealed, triple-insulated glass with two Low E surfaces and two krypton/argon gas-filled insulated airspaces for maxi¬mum efficiency. How do I decide between single-, double-, or triple-glazed windows?

Single-glazing is a single pane of glass and is best used in garages and tool sheds—buildings that don’t need to be extremely energy efficient. Double-glazed windows have two panes of glass with either air or a safe, colorless and odorless gas tightly sealed between the panes. When its glass is treated with Low E coating, the window can achieve a value of R5 at the center point of the glass. The most energy efficient window is a triple-glazed window. Gases are sealed between three panes of glass and Low E coatings are applied on two of the panes. This can bring the energy efficiency up to a value of R10 at the center point of the glass. Does argon or krypton gas between glass panes really make a difference in energy efficiency?

For air to insulate well, it needs to be as still as possible because moving air carries energy. Both argon and krypton are heavier than air—so they’re less prone to convection or thermal movement. The bottom line is that heavier-than-air gases offer a higher level of insulation. Both argon and krypton are found naturally in the air you breathe and are completely harmless. What are jambs?

Jambs are framing members used to support the window in the wall. Those framing members on the side are, logically enough, called side jambs. The framing member at the top is a head jamb. There are no jambs at the bottom. This framing member is referred to as a sill. What are mullions?

Mullions are vertical members between window units. They are sometimes confused with mountings, which are secondary framing members that hold multiple panes of glass in the sash. Other parts of the sash include stiles (the outside vertical members) and rails (the top and bottom horizontal members). How important is weather-stripping?

Very. Weather-stripping is important because it provides the barrier against air and water in windows and doors. It is the only element of operating windows or doors that make them reasonably air tight. High-quality weather-stripping that’s applied and compressed properly really does improve the insulating performance of windows. What is an impact-resistant glass window?

Impact-resistant glass has strong laminated glass interlayers. When combined with an exceptionally strong win¬dow frame, this type of window provides homeowners with greater security and protection from storms, flying debris and even the occasional stray golf ball. When struck by something hard and forceful, like a tree branch or softball, the glass resists shattering. In the rare event that an object impacts the glass, the pane may shatter, but it remains held within the frame. This greatly reduces the risk of flying glass, water or debris penetrating into the home. Who should have impact-resistant glass in their homes?

Homeowners living in coastal areas prone to strong winds and storms, or who live directly on a golf course or in an area where vigorous sports activities take place, should consider impact-resistant glass in their homes. Other homeowners might be interested in the sound reduction and security benefits which impact-resistant glass provides.

I was reading the article that Randall Kennedy, on InfoWorld, wrote about the relative ease with which Windows 7 installs, comparing it to each revision of Windows, going back to Windows NT.

He gives a picture of the problems of each of the operating systems, from his own perspective, and for the most part, I agree -

Windows NT: Setting up a Windows NT workstation was always a hit-or-miss proposition. Many common devices, like nonstandard IDE hard disk controllers, though perfectly happy under DOS/Windows 9x, would give Windows NT fits.

Any such reinstallation project usually required several days and involved at least one bricked attempt where a driver hosed the boot cycle and the Last Known Good Configuration option somehow lost it bearings. This was especially true when you added any number of unsupported third-party mobile power management tools into the mix.

Yes, there was always a point at which you knew the easiest fix was “Format C:\” and then re-install. The bad part was over when you were done with the floppies.

Windows 2000: Like Windows NT, but with a half-baked plug-and-play mechanism to give you false hope that somehow the system would right itself. It rarely did, and most Windows 2000 installations quickly devolved into the kind of blue-screen troubleshooting sessions that were supposed to be a thing of the past. Still, a better-organized setup program — including some crude hardware autodetection — helped to shave a couple of hours off the marathon.

Actually, I really never had that many problems with the original install of Windows 2000. Perhaps it was because I never used it with 2nd or 3rd tier motherboards. I think that the BIOS was key in these cases, and the freaky, oddball AMI concoctions that some motherboards had was something to behold.

Windows XP: An attempt to meld the ease-of-use of Windows 9x with the robustness of the NT kernel, XP was a disaster out of the gate. Many Windows 9x drivers, though theoretically compatible with XP, simply didn’t work (NDIS driver support was a notable gray area). And some legacy NT drivers that worked fine under Windows 2000 simply refused to cooperate under XP.

It took nearly a year to shake out the whole hardware compatibility mess, and by then enough new standards and architectures had emerged to ensure that future XP installations would require much patching and tweaking (F6 for the driver floppy disk, anyone?).

I must lead a charmed life, because I have never had many problems with Windows XP installs. The hardest thing about XP installs was the waiting for that final reboot. It became less and less a problem as computers, and especially hard drives, sped up, getting down to full installs in about 12 minutes, though the installer always said it would be thirty-nine.

Windows Vista: Windows Vista had the potential to be the easiest version of Windows to install ever. And in most respects, it was — at least up to the point where you actually wanted to use it for something productive. Then it became a waiting game as you listened impatiently for news of Nvidia or ATI releasing yet another prerelease driver for your state-of-the-art video card, the one you paid extra for in anticipation of Vista’s Aero goodness.

And then it was install-and-pray time — pray that, maybe this go-round, the company had gotten it right. That you wouldn’t be rewarded for your patience and fortitude by a wonky release, with missing features or — worse still — the kind of instabilities that nearly sent you running back to XP with the last prerelease.

Eventually, the mess would get sorted out, with vendors accepting the fact that new technologies, like WDDM, were here to stay. But for a good year and a half after Vista went “gold,” creating a stable, working environment was a real challenge. No wonder so many of InfoWorld’s readers demanded that Microsoft do something and save Windows XP.

Indeed, it has been a long, rocky road that led me to this point — a point where I can install a version of Windows and have it successfully recognize the majority of the hardware in my system. A point where, even it if Windows doesn’t recognize something funky, Windows Update — that bastion of false hope in every previous iteration — will usually find a compatible (if generic) driver. And a point where a visit to my hardware manufacturer’s Web site rewards me with a healthy selection of new and updated drivers, all designed to ensure a smooth transition to Windows 7.

It was a long time coming, and perhaps the geeky side of me will miss the visceral challenge of a good old-fashioned, blood-pressure-raising, hair-thinning Windows installation. But the rational side is happy to see things finally improve to a point where Windows just works out of the box — and where the drama in my life is restricted to the day-to-day struggle of raising two disturbingly tech-savvy pre-teens.

Windows Vista was something I have only installed for myself twice, but I have re-installed it many times for customers. That was enough for me. Vista was, and is, a pain. But Vista is a pain completely due to Microsoft. They changed things that did not need to be changed, and kept trying to convince us that they were right in doing it.

I remain unconvinced, especially when I read what Mark Russinovich has said about the reasons for the changes.

In many of these cases, all of the blame was not on Microsoft, because many things were installed that were difficult to program. There used to be many types of odd hard drive controllers in the days of Windows NT, and today, there are not that many people who have a clue what they were, and are totally clueless when you talk about the many quirks that there used to be. Today, though not widely used, SCSI is a breeze to set up. When I started using it, that was not the case. I was kind of a SCSI guru, but it took many hours of frustration to get the title.

There were many other things that used serial interface and parallel interfaces, and the items did things that the designers of these ports never imagined. Since that was the case, sometimes there were amazing things happening when you tried to make the items work.

There were also things that happened that programmers of software were not prepared for, though they should have been. The rules of the game ( the IBM PC game, that is ) said you could do them, but instead of taking that into account, programs were designed stupidly (some still are) making assumptions about where they were installed, or should be installed. Virtually no one has 4 floppy drives on their machine any more (during the time from 286 to Pentium, I built every machine that was for my own use with 4 floppy drives, and they were sometimes A:,B:,C:, & D:, which meant that the first hard drive was E:); lots of programs did not like that.

I used to do things because you were supposed to be able to. I had several 486 class machines with 3 VESA Local Bus cards, which, though part of the standard, few motherboards were built well enough to allow it. It was not easy getting them to work, though it should have without problems.

Most people today look at the computer as an appliance. They are not as much a hobby pursuit as in times past. Also, with the loss of COM and Parallel ports, things are easier, with fewer surprises due to USB connectivity and standardization. The fact that hard drives are much larger means that fewer drives are seen on some enthusiast’s systems, and most likely they are all SATA.

Plug and play actually works most of the time, and there are much more standardized BIOS implementations. all of these things have contributed much more to the ease of Windows 7 than what Microsoft has done. It has all been laid at their collective feet. The fact that Microsoft no longer really worries about code optimization ( I’m talking the kind where it’s done by doing it by hand with assembler! ) also makes things easier.

So it’s been a long road, but Microsoft has not been the only commuter.

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