Windows (Not The One We Always Use With Our PC)

Selamat Hari Raya to all the Muslims in the world. It must be such a joyous day to have all the families sitting down together and enjoy the meals. For me, it was fun to visit my Malay friends where we had the ketupat and curry chicken. When I visited their homes, I was so surprised with the airflow in their house. They do not require air-conditioning to cool down their traditional house. And surprisingly, some of their windows were tinted. So I'd searched in the Internet about the windows that are capable of saving electrical energy bills and there are many results in the Net.

So What Are Windows?

Windows provide our homes with light, warmth, and ventilation, but they can also negatively impact a home's energy efficiency. Windows can be one of your home's most attractive features. Windows provide views, daylighting, ventilation, and heat from the sun in the colder days. Unfortunately, they can also account for 10% to 25% of your heating bill by letting heat out.

During the hot weather, your air conditioner must work harder to cool hot air from sunny windows. You can reduce energy costs by installing energy-efficient windows in your home. If your budget is tight, energy efficiency improvements to existing windows can also help.

How to Improve Energy Efficiency of Existing Windows?

You can improve the energy efficiency of existing windows by adding storm windows, caulking and weatherstripping and using window treatments or coverings. 

Adding storm windows can reduce air leakage and improve comfort. 

Caulking and weatherstripping can reduce air leakage around windows. Use caulk for stationary cracks, gaps, or joints less than one-quarter-inch wide, and weatherstripping for building components that move, such as doors and operable windows.

Window treatments or coverings can reduce heat gain in the hot weather. Most window treatments, however, aren't effective at reducing air leakage or infiltration.

Energy Efficient Windows

If your home has very old and/or inefficient windows, it might be more cost-effective to replace them than to try to improve their energy efficiency. New, energy-efficient windows eventually pay for themselves through lower heating and cooling costs, and sometimes even lighting costs. When properly selected and installed, energy-efficient windows can help minimize your heating, cooling, and lighting costs. Improving window performance in your home involves design, selection, and installation.

There are four factors to be considered when choosing energy efficient windows: frame, glass, design and installation.

Frame: A wood frame is less prone to heat and cold transfer than an aluminium. This is because metals conduct temperature much easier than wood. But that doesn't mean wood is always the best choice for a utility-bill-friendly window. There are a variety of materials such as vinyl and wood clad which are available for window frames, and each has positive and negative aspects. It's up to you to decide what's best for your style and your budget. You may consult to the supplier.

Glass: While the material that each window is constructed from is important, the reality is what's the most important are all about what's inside the frame. A double-paned window with Low-E glass, with a vacuum-sealed argon fill can help in the energy saving of a building. A Low-E, argon-filled, double-paned windows provide significantly more insulation than a single-pane window. These windows protect the inside of the house from the sun's heat and UV rays in the hot days, and they prevent heat from escaping during cold days. From the standpoint of energy efficiency and value, these types of windows make a lot of sense. Like the energy savvy people always say: "just adds cost and gives diminishing returns in efficiency". When you go out and buy a window, you may check out this rating:

• U-value: measures a window unit's resistance to heat loss
• Solar Heat Gain Coefficient (SHGC): measures how much heat enters a home through the glass

Design: There are many types of window design out in the market and you will have to choose smartly on which design suits your home or office. Some window designs are inherently more efficient than others. The most common types:

• Double-hung windows: These are traditional units in many homes across the country, and they're especially common in old buildings. With double-hung windows, the bottom slides up to open the unit. They can be efficient choices, but in really extreme climates, they may not be the best option because of the potential for air intrusion between the sliders.
• Casement windows: Popular in climates where wind is an issue, these units which have a crank that swings the window outward to open, actually seal themselves off tighter when wind blows in toward the house. However, they do require maintenance on hinges and seals to ensure their continued stability and efficiency.
• Picture windows: These windows usually don't open and come in many different shapes and sizes, but that doesn't mean they can't be efficient — glass choice and gas-filled interiors are especially important in these larger units.

Installation: You will still have the same energy losses although you have  put up an energy efficient window if there's no proper installation done. Don't overlook the importance of proper installation because even the most expensive window unit won't perform effectively if it's not installed correctly. You must always be wary of any contractor who relies too heavily on expanding foams or sealants to get a window to fit well as these materials aren't waterproof and can lead to problems down the road. Pre-installation waterproofing, often completed long before windows are installed, is the best option. Flashing and proper caulking may be the cheapest parts of window installation, but if they're not done with an eye to detail, the ensuing water leaks will cause a barrage of problems that should have been easily prevented.

Cost

An energy efficient window can cost about RM30k to RM57k for a typical home. The range for energy-efficient window pricing is wide, but Energy Star-qualified windows start around RM350 for a 36-inch-by-72-inch, single-hung window and can go up to 10 times of that. With labor, you’re looking at about RM1,000 to RM3,000 per window. Typically, windows at the low end of the price spectrum are less energy efficient.

But that doesn't mean the numbers can’t make sense for you. For starters, window replacement is one of the best home remodeling projects in terms of investment return: For vinyl windows, you can recoup 72.9% of the project cost in added home value, which provides national averages for various remodeling projects. The Return of Investment (ROI) on wood windows is at about 78%.

You’re most likely able to see modest savings on your energy bill. In general, you’ll save roughly RM500 to RM1,800 a year if single-pane windows in a 2,000-square-foot house are replaced with energy efficient windows. Keep in mind, though, that the savings can vary widely by climate, local energy costs, and the energy efficiency of both the windows purchased and the windows being replaced. The most efficient windows on the market are usually the most expensive, but it’s not necessary to buy the highest-end products to realize utility bill savings or improve comfort and aesthetics. For that reason, think long and hard before committing to new windows.

Pros & Cons

Advantages of Energy-Saving Windows

An energy efficient window consists of two or more panes of specially-treated glass with a layer of an inert gas, such as argon, trapped between the panes. Argon does not transfer heat well and so acts as an energy “blanket” between the sheets of glass, preventing the room’s warmth from escaping through the window.

Energy-efficient window glass is also specially treated with a thin film of metallic particles which are designed to reflect away the sun’s UV rays while at the same time trapping the heat that is in a room and reflecting it back into the home. The result is an immediate saving on utility bills for the homeowner, but more than that, the view through an energy efficient double-paned window is virtually as clear and unobstructed as the view through an untreated single-pane window.

There are standards (depending on each region) that rates windows for their insulating properties, their visual transmittance (how easily they can be seen through), their solar gain coefficient (how well they protect a room from the sun’s heat and UV rays) and air leakage around the edges of the windows.

The new energy-efficient glass is more expensive than old-fashioned standard windows. However, the initial cost should not be the only factor when deciding on new windows. By calculating the energy saved each month, we determine how much money will be saved each month on utility costs. In this way the homeowner can see exactly how long it will take for the new windows to pay for themselves and how much extra money the homeowner can enjoy each month. The homeowner should also keep in mind that as energy prices rise in the future, their savings will also increase with time.

One final advantage to double-paned windows is outside noise reduction. Homeowners who replace single pane windows with double paned windows, especially windows with a high Energy Star rating, report that street noise is reduced considerably, making for an overall more comfortable living environment.

Disadvantages of Energy-Saving Windows

Probably the biggest drawback to energy windows is the initial cost. Many homeowners, especially if they are planning to replace a number of windows, might see costs of 10% to 15% more for double-paned energy windows as opposed to double paned non-energy efficient windows. For a home with several windows, the added cost can increase the bottom line quite a lot. Double-paned windows are heavier than single paned windows, and for some homeowners that might be a drawback.

In order to see any significant energy savings each month, a homeowner must replace all older windows with the new, higher-priced energy efficient windows at the same time. No appreciable savings will result from simply replacing one old, leaky window with a new high-efficiency window while leaving all the others in place. However, replacing all the windows at the same time can be a large job and can also be expensive.

It is also necessary for homeowners to be quality-conscious when buying high-efficiency windows. Off brands or cut-rate windows may not be properly sealed and can cause more problems than they solve. Poorly insulated double-paned windows can allow condensation to form between the windowpanes, indicating that the windows are not doing their job properly. Saving money up-front by buying lower-priced windows may not result in the energy savings that the homeowner had planned on. This situation can be eliminated by only dealing with reputable companies who have years of experience installing high-efficiency windows and who only sell quality windows.

Should You Change Your Windows?

Although replacing old windows with energy efficient ones will save you money on your energy bill, other approaches can be more effective and cost you less to implement.It is recommended that the homeowner should start with window insulation, which can be as simple as covering the windows in plastic. You should first check your home for leaks, including heating and cooling ducts, doors and cracks. Improve your home's insulation but consider replacing windows if you notice moisture entering your house because that can lead to mold growth, which is more dangerous than high energy costs.