The most important thing to know about installing or replacing your windows
Whether you're building a home or doing some renovating, the decision of what kind windows to buy, or whether or not your windows even need replacement, should be made on more of a practical basis than an aesthetic one. After all, the cost of replacing the windows in an average house can amount to a hefty sum, nearing and possibly exceeding five figures. Knowing how to get the most benefit from that investment is a simple matter of assessing your situation.
When you're building...
If you're in the process of building a home, you're pretty much locked in to having to make that investment, but by installing energy efficient windows, you can recoup some of that cost throughout the time you're living in the home. Windows that don't have some form of insulative properties can be the greatest cause of unwanted temperature fluctuation in a home, allowing in more heat in the summer and cold in the winter and making your furnace or AC work extra hard to compensate. By installing windows that contribute to a homes heat retention, you can start shaving money off of those pesky utility bills.
When you're renovating...
Unless you're just really fired up about getting energy efficient windows, the other reason they might be on your mind is that you've decided it's time do some renovating. This could be because you want to spruce up the look of your home so you feel comfortable in it for years to come, or because you've decided it's time to sell and you want to boost your market value. In either case, the high cost of installing new windows means that you're paying a lot for relatively little design impact. However, in the case of doing renovations for a home you intend to keep as your own, installing energy efficient windows can save hundreds of dollar per year, so if you are planning on staying there for a long time, you can make back a significant portion of the cost of installation, or perhaps even all of it.
When looking to sell your home, it's true that energy efficient windows are an appealing feature to buyers. While they may make your home sell faster, its difficult to earn back in the sale what you put into them, so make sure you know what you value more in this instance: your time, or your money. If what you really want is to sell your home for more money, know that buyers usually pay more for what they can see, so redoing your kitchen or flooring, or anything visually prominent, will likely be a safer investment than windows.
From a design perspective, you want to tailor the look of your windows to the feel of your home. Expensive windows on a low to mid-range home will look just as out of place as cheap windows on a mansion, so if your windows do need replacement because they're either in a state of disrepair or lacking in energy efficiency, let those be your primary concerns and use the rest of your budget to improve the look of other parts of your home.