Window replacement projects are a big proposition for any homeowner. Making an educated decision is critical, and any time spent in the planning phase is well worth the investment. This is particularly true if you are researching on behalf of your association, which may include hundreds of homeowners.

In a condominium, the first order of business to be discussed in a window replacement project is the community's aesthetic requirements. New windows will need to comply with the architectural integrity of the complex. After that, the next priority on the list is finding the most energy-efficient model.

How to Choose

To make an educated choice, don't be afraid to ask for assistance. Your best bet is to begin by contacting window manufacturers, who will offer contact information for local retailers. In most cases, retail outlets offer not only windows and doors, but also installation services, if your association is shopping for both. Proper installation plays a major role in the overall success of an energy-efficiency plan.

Once a window style that meets the community's criteria is identified, buyers must select from the many products on the market, including wood, vinyl, aluminum, and fiberglass. Fiberglass is now leading the way on many levels.

Energy Efficiency Sells Itself

In addition to its other benefits, fiberglass is more energy-efficient because it is 500 times less conductive than aluminum and insulates much like wood and PVC. As a result, fiberglass windows and doors provide an insulated barrier against extreme weather temperatures, keeping your home more comfortable and reducing heating and cooling costs. These considerations are extremely important for those of us who live in New England, which is known for offering a wide range of temperatures across the seasons. While there are many benefits to using fiberglass, not enough can be said about the energy efficiency it offers when it is used in the construction of windows and doors.

Promoting an energy-efficient home environment is no longer a tough sell for condominium complexes, but it is important to know what you are looking at as you move into the window selection process.

The energy efficiency qualities of a window are not equal across all brands. To identify the most efficient windows, the U.S. Department of Energy and the U.S. Environmental Protection Agency established the Energy Star rating system. The rating indicates that a window has met specific performance requirements for energy reduction. If a window product has earned an Energy Star rating, a label with the Energy Star logo will be prominently displayed on the product. Many options are available in many window lines, but not all of the combinations earn an Energy Star rating, so it is important to understand what you are purchasing.

Many people wonder why Energy Star ratings on windows are so important. The rating is key because windows that earn the Energy Star rating may reduce your energy consumption—and, therefore, your energy bill—by up to 15 percent. Savings are greatest in areas that experience hot summers and cold winters, such as here in New England.

Another resource for homeowners who are comparing the energy efficiency of windows is compiled by the National Fenestration Rating Council (NFRC), a not-for-profit organization that sets standards for the window and door industry. Because the organization operates outside of the window and door manufacturing process, its review is fair and objective. NFRC ratings measure light transmission and heat loss or gain under varying conditions. Look for the NFRC sticker on approved products, and log on to www.nfrc.org for more information.

A Pane in the Glass

Determining what makes a window energy efficient can seem daunting. But there are some basics to keep in mind. The main components of a window are the frame and the glass. Windows include other parts as well, but these two components are the most critical. Having devoted some space to contemplating the frame construction, also worth considering is a window's glass. The glass constitutes the largest area on the window—approximately 75 percent of the window's surface area.

If a window is outfitted with only one pane of glass, the glass, or glazing, offers virtually no insulation. To adequately insulate New England homes from heat loss during the winter months and solar heat gain during the summer season, a window must include multiple panes of glass. Your unit may be outfitted with double-paned windows now, but the windows' performance may be compromised because the seals may have failed over time, which, in turn, leads to condensation and drafts. These problems are very common to vinyl windows, which were often installed in condominiums throughout the Northeast. Over time, the windows have endured years of temperature fluctuations, which causes the window to expand and contract. The problems that result become particularly noticeable during winter months.

When evaluating a window, there are two important terms to bear in mind: U-Factor and R-Value. The U-Factor is a measure of total heat flow through a window or door barrier from room air to outside air. Lower numbers indicate greater insulating capabilities. The R-Value is the resistance a material has to heat flow. Higher numbers indicate greater insulating capabilities. All windows have these values, but the numbers vary and largely depend on the number of panes a window includes.

To dramatically boost the energy efficiency of a double-pane window, select a model with Argon gas between the panes (which is standard for most windows). Argon gas is an odorless, colorless, non-toxic gas that insulates a home from heat loss and solar gain by minimizing heat transfer. The overall performance of window glass is increased even further if the window is also outfitted with Low E II, a special coating that reflects infrared light, keeping heat inside in the winter and outside in the summer. Low E stands for "low emissivity" and is designed to improve thermal performance. Low E II glass is coated twice with microscopic metal or metallic oxide layers to reflect or absorb the sun's warmth, as well as reduce the damage from UV rays to rugs and furniture. Finally, the addition of spacers maintains window panes in the correct position to one another. Today's spacers, which are made of steel, reduce heat flow and prevent condensation. While Low E II, Argon gas, and spacers are standard on most windows, it is important to make sure they are included in the model you are considering. If energy efficiency is important to you, all of these are must-haves.

Final Considerations

A strong relationship exists between the window glass and the frame that surrounds it. A frame made of fiberglass will expand and contract at virtually the same rate as the glass within the frame because they have the same properties. This plays a major role in not only the overall insulation properties of the window unit, but also in the life span of the window. Vinyl, by contrast, suffers because of expansion and contraction problems that are inherent to the material, and aluminum is a poor insulator against the outside elements, making fiberglass the perfect solution. An extra benefit of a window replacement, although not typically cited at the outset—is that new windows, in addition to offering insulation properties also dramatically reduce the level of outdoor noise that makes its way into a home. Whether you live in a large or a small condominium environment, a quieter home is always welcome.

For any homeowner who is interested in maximizing energy efficiency, it is key to understand how a window's frame and glass interact. Identifying window brands that offer the best opportunities to maximize these efficiencies will make for larger savings over the long term.

In the final installation of this series on window replacements, we'll take a look at what makes fiberglass not only a top performing window solution, but also a low maintenance and aesthetically pleasing choice for your condominium.