Replacement windows: how many years can they last?

Windows are some of the most important, distinctive features on any home. They let in the view, sunlight and pleasant breezes; they lock up tight to keep out nasty weather and unwanted intruders. The best ones do it all in style and keep your home insulated for decades. Picking out the best windows for your home is a big decision, and not all window types were created equally.

When is it time to replace windows?

Sometimes windows just get broken, but most of the time this isn't the motivating factor in replacement -- particularly for an entire house. Here are two common issues that often get the window-replacement conversation started:

*Fogginess or condensation. Double-pane windows have a space between the panes filled with air or inert gas. As the window is exposed to varying temperatures, the fill and the seal around it both expand and contract. Eventually this causes the seal to break down, letting in outside air and, with it, moisture. Double-pane windows can last eight to 20 years, but if moisture gets between the panes, you might notice condensation and fogginess. A desiccant is often used as a temporary measure to dry up the moisture. One of the most common desiccants, silica, can form a haze that goes above and beyond just that of trapped moisture.

*Lack of function. Eventually windows just stop working, whether because of broken hardware, warping, rotting, abuse or any number of other issues. Sometimes the problems can be fixed as they occur, but unfortunately, this isn't the case with all window types. The expansion/contraction cycle that happens everyday as windows are cooked by the sun and cooled at night is responsible for many, if not most, issues. Severe weather accounts for most window failures not caused by accident or abuse. Skylights, no matter the window type, suffer the most from weather and sun without the protection of awnings or other coverings and only have a life expectancy of 10 to 20 years.

Window types, costs and life expectancies-

So what type of windows will best fit your needs, your climate, your home and your taste? Below, you'll find a breakdown of the most common replacement window material options:

Aluminum and aluminum clad windows: Aluminum is a highly versatile material for window construction, allowing for custom shapes. It's also an incredibly durable material that doesn't rot or rust in the face of the elements. The big issue with aluminum windows is their conductance, which lets the heat and cold of the outdoors right inside. To solve this issue, many manufacturers have started offering windows made from other, more thermally efficient materials clad in aluminum, giving you the durability and versatility of aluminum without the downsides. These windows last 15 to 20 years without maintenance. Expect to pay between $100 and $250 each for strictly aluminum windows -- and add $100 per window for aluminum-clad.

*Vinyl windows: One of the most popular options on the market today, vinyl windows are found on homes across the country. They never need to be painted, are thermally efficient and can be made to match almost any home. Vinyl expands and contracts more than other materials, though, which makes them more prone to failure than other types of windows -- especially in high-heat situations. These windows are expected to last 20 to 40 years, but since they are relative newcomers, only time will tell. You can get basic vinyl windows for around $100 a piece and larger, more complex models for as much as $400 each.

*Wood windows: Wood windows are tried-and-true classics. Wood is naturally very thermally efficient, and it's easy to work with, which makes it easier to find custom shapes. Maintenance is the biggest downside with wood windows because they require painting and sealing. Let this maintenance slip, and you could be giving wood rot a free ticket in. Unlike other window types, though, wood windows are fairly easy to repair because individual parts can be replaced as needed -- even if it's only half of a window sill. Due to the ease of repair, life expectancy for windows is 30 years or more -- a lot more with proper care. Wood windows can run anywhere from $200 to $600 each.

Screens, shutters, awnings, storm windows and other protection from the elements can greatly increase the thermal efficiency and lifespan of your windows. Windows are a large investment, so be sure to thoroughly research and weigh your options before deciding which ones to get.