Green Energy Efficient Homes | Best energy efficient windows

New efficient windows can save you a bundle on heating and cooling

The best energy efficient windows now available are significantly more energy efficient than even the current minimally certified ENERGY STAR windows. Before you look at house window replacements or a volume window purchase for a new house it helps to understand what makes high efficiency windows truly energy efficient and what features will maximize your comfort and minimize energy use.

In this article I will describe key features of the best energy efficient windows, the current ENERGY STAR standard and the new R-5 standard for high efficiency windows, ways you can make your existing windows more energy efficient without replacing them, and the Windows Volume Purchase program which helps US residents buy the most energy efficient windows at a volume discount of up to 20% from selected suppliers.

Key features of energy efficient windows

The best energy efficient windows cut your home energy costs in four ways, the first three of which are directly related to how heat is transferred from one object or space to another:

The following illustration should help you understand the four ways in which heat is transfered from one side to the other of a window:

Bear in mind that we’re talking about heat transfer both when you’re heating your home, and when you’re cooling it (or trying to keep it as cool as possible without air conditioning). The same principles apply to both situations: you want your high efficiency windows to be as strong a barrier as possible to heat transfer, from the hot side of the window to the cold side. The only difference is that in winter in cooler climates, you want the heat from the sun to radiate into your home, but you don’t want heat from inside to radiate out; while in summer or in hot climates, you don’t want heat from outside radiating in.

Double-glazed window cross section

Which of these heat transfer mechanisms do you think is the most important when looking for house window replacements? They’re all important, but airflow is the most important, at least if your current windows are more than 10-20 years old. If you check the illustration, you’ll notice a squiggly air current moving from the indoors to the outdoors, between the main part of the window and the wall below. This represents a draft, which is the main way in which most homes lose energy through their windows.

Drafts can occur in cracked putty on old hand-glazed windows, cracked glass, cracked wood in wooden window frames, and improperly sealed moving sashes or casements in movable windows. Drafts can also occur in the window framing, and even in the area of the wall around the window frame.

In general, when looking at house window replacements, the biggest benefit of replacing your windows with high efficiency windows is that the best energy efficient windows cut down on many of these types of drafts. And while the ENERGY STAR windows specification does not have any requirements as far as air leakage, the newer, more stringent R-5 standard does require minimization of air leakage.

Convection affects window efficiency as well as your comfort indoors, particularly in winter. If the inside glazing is cold (because too much heat is being conducted outside through the glass and the gas filler between panes of glass), warm air from the room will cool as it strikes the glass, and that air will then tend to fall (since warm air rises and cool air falls). The falling cool air draws warmer air in its place, creating a convection loop that lets the window glass continually pull heat out of the room, all the while your ankles get colder.

I’ll point you to some resources a little later that can help you deal with the convection currents inside your room to turn your existing windows into high efficiency windows, or that can make the best energy efficient windows even more efficient. Hint: dress up your windows.

Most high efficiency windows have two or three layers of glazing, with space between them to act as a barrier against heat conduction. The space between the glazing layers is filled either with air or with an inert gas such as argon or krypton.

Ideally you would want a vacuum between the two panes – as little gas as possible to minimize heat conduction – but unfortunately this has the effect of pulling the two panes together, risking breakage, and since, as Faulkner taught us, nature abhors a vacuum, a vacuum-sealed double-glazed window has a tendency to develop leaks and fill up with air.

The reason a vacuum would be ideal in the best energy efficient windows, is that if there was no gas between the two panes, only empty space, there would be nothing for heat to be conducted through. (That’s why your thermos has a vacuum between the inside and outside walls of the container.)

Since a vacuum isn’t a viable option, the next best choice for the most energy efficient windows is a gas that has very low thermal conductivity, and is also non-reactive. Some common gases and their thermal conductivity (in W/mK) are:

You’ll notice that krypton has the lowest thermal conductivity of the bunch; unfortunately it is rather expensive, so is only used in a small percentage of the most energy efficient windows (particularly triple-glazed windows where the thinner space between panes allows a smaller amount of the gas to be used). Carbon dioxide has low conductivity as well, but can be reactive when it meets moisture, so it’s not suitable for a glazing gas. Argon is the next best gas, and is used extensively in the window industry to produce the best energy efficient windows. If you are buying ENERGY STAR windows or the new R-5 windows, you’ll almost certainly be looking at windows that are filled with either argon, or a combination of argon and krypton.

Conduction through the solid parts of the window is the second way that conduction affects a window’s energy efficiency. A window frame made of a single piece of aluminum will conduct a lot of heat from the warm to the cold side, which is why aluminum window frames tend to gather a lot of frost around the edges in winter. Efficient aluminum window frames need some kind of thermal break between the indoor and outdoor portions of the aluminum; even so, these window frames are still less efficient than other types. Aluminum frames are definitely less popular than they were 10 or 20 years ago because of this, although some newer wood-cored frames are clad in aluminum. Here are the R-values of five different types of window frame material; higher is better. You’ll notice that all three versions with aluminum in them are less efficient than their vinyl cousins. The most energy efficient windows are almost always vinyl or fiberglass.

Notice the difference between the top and bottom types in the list? An insulated vinyl window frame has an insulation value between 6 and 12 times better than that of an aluminum frame with no thermal break, and between 1.3 and 3.3 times better than that of any aluminum-based frame. The message here is clear: aluminum is a poor choice for the best energy efficient windows.

Radiation through the glazing is the third type of heat transfer that affects a window’s energy efficiency. Radiation is really the same thing as light. Infrared radiation is long-wave radiation that you feel directly as heat. Visible light is shorter wave radiation; when intense visible light from the sun strikes an opaque surface, such as your face or a table or floor indoors, it turns to longer-wave infrared radiation.

How much visible radiation a window lets through is important for two reasons. In climates where keeping your home cool is important, you want to minimize visible light entering your home through windows, because it will turn to heat indoors. In cooler climates where you have the heat on for part of the year, you want to maximize light entering your home so you can take advantage of free heat from the sun. And you want to minimize infrared radiation passing from the warm to the cold side of the glass in either case.

Manufacturers of the most energy efficient windows address infrared heat transfer by applying specialized surfaces called Low-E coatings to the window glazing. These coatings reflect infrared light back to where it came from, rather than let it pass through, which significantly reduces the radiant heat gain you get from the best energy efficient windows.

Low-E coatings are applied to the best energy efficient windows to cut down on thermal radiation between the panes of glass in a double- or triple-gazed window. By coating one surface of one or more of the panes with a microscopic low-emissivity coating, window manufacturers can cut back on this radiant heat flow. The coating is most effective when it is applied to one of the surfaces between the panes – the inside surface of the outer pane, or the outside surface of the inner pane. These coatings block much of the radiant heat, and can have a significant impact on window efficiency. What’s more, the coatings can be more effective at blocking radiation in one direction than in the other.

You should select windows with a low-E coating that is suited to your climate. The three types of climates to consider are heating-dominated, cooling-dominated, and moderate climate with a mixture of heating and cooling. For heating-dominated climates you should look for a low-E coating that allows maximum solar gain (so you can benefit from solar energy in winter to help heat your home). Such coatings allow up to 71% of solar heat through the window glazing.

For cooling-dominated climates, you’ll need a low solar gain glazing, which reflects most of the solar radiation back to the out of doors – allowing as little as 27% of it into the indoors.

For climates between the two – those where you run heating and air conditioning about the same amount of time – you should look for low-E coatings that provide a moderate solar gain, somewhere between the 27% and 71% solar heat transmission.

Coatings can also be applied to tint the window to reduce the amount of visible light entering the room. A measurement called VT or visible transmittance gives you an indication of how close the window comes to allowing all light through it. A VT of 100% is equivalent to a hole in the wall – a window with no glass, such as they used a thousand years ago in castles in England! A VT of 60% or more will generally appear completely untinted to most observers. In hot climates, you may want a VT lower than 60% because reducing the amount of visible light entering your home will cut down on heat gain, as you’ll have less light indoors to turn into heat. But you don’t want to cut down on the light so much that you then have to use more indoor lighting, as you’ll pay twice for that – once for the electricity to power the light, and again for the extra energy it will take an air conditioner to move the heat from that light out of your home. (Of course if you use fluorescent or LED lighting the heat gain from the light will be minimal.)

The best energy efficient windows therefore combine features to address all of these heat transfer mechanisms: air leakage, conduction, convection, and radiation.

How to determine if you need to replace windows

When you’re considering house window replacements it’s important to bear in mind that not all energy loss through windows is easily detected. If you have old single-glazed sash windows with aluminum framed (or even wood framed) storms outside, you will almost certainly see signs that you need house window replacements: gaps where the storm meets the window frame, cracked putty, cracks in the glass, the pulley openings for counterweights are all potential sources of air leakage, and you can often feel the cold air blowing in on a winter day.

Likewise if you have newer double- or triple-glazed windows with aluminum frames, you may see the condensation (or even frost) building up on the inside of the frames on a cold day, as heat from the room is wicked outside and the cold surface of the frame causes condensation. Or if the seal is broken in a newer double-paned window and the argon gas has been largely replaced by air, you’ll notice more condensation on that window on cold days than on others.

But some signs are less obvious, and sometimes even the experts don’t understand the factors that determine whether windows need replacing, and what kind of house window replacements to get.

My brother is a statistician and an energy efficiency nut like me. He once called a window installer to give him a quote on replacing his old aluminum-framed windows. He wanted the best energy efficient windows he could get – he heats with electricity, and every dollar he spends cutting the amount of heat escaping his home through cold Ontario winters has the potential to save him ten or twenty dollars in heating costs.

He told the installer he wanted low-E windows, and the installer told him it’s not really worth it – that he would be paying 20% more for the windows and only saving a few dollars a year on heating. So my brother pulled out his laptop, opened a spreadsheet he’d prepared, and plugged in the numbers: the amount of heat loss through his current, inefficient windows, the regular new windows the installer was pushing, and the best energy efficient windows available. While the most energy efficient windows had a much higher up front cost, over a 20-year life they would save him enough money to cover not only the increased up front cost, but the entire up front cost!

The installer was surprised. Even after years of selling and installing windows, he had never done such a calculation. “I guess that’s why you’re a statistician and I sell windows,” he said!

The point of this anecdote is twofold: first, that the savings from getting the best energy efficient windows can be substantial; and second that most people selling you windows – even people who claim to be looking out for your financial interests – have no idea what the full life cycle costs of different window efficiencies are. If you spend more than a few hundred dollars a year on either heating or cooling, you will definitely be better off if your house window replacements are as efficient as possible.

You should consider replacing your windows with new energy efficient windows if any of the following apply:

ENERGY STAR standard for windows

If you buy new ENERGY STAR windows you at least know that you are getting a guaranteed minimum efficiency level in your house replacement windows. But the ENERGY STAR standard is definitely not all that stringent by today’s standards.

Set in 2003, the ENERGY STAR specification for windows and doors requires different maximum U-factors for different climate regions of the USA. Remember that the lower the U-factor, the less heat can pass through the window – including through glass, frame and spacers. Factors ranged from 0.65 for the Southern climate region (Florida and the southern ends of Texas and states in between), to 0.40 in South/Central and North/Central regions, to a maximum efficiency of 0.35 in the Northern region (representing roughly the northern half of the Continental US).

Low U-factors are most important for increasing the efficiency of home heating. Low U-factors help reduce cooling costs in warm climates to a lesser extent than heating. U-factor is basically the inverse of R-factor, so a U-0.4 window is the equivalent of R-2.5. A typical 4″ stud wall will have R-12 to R-16 in it depending on the insulation used – that’s why windows, while a small part of a typical house wall surface, are a large part of the heat transfer.

If a window company or installer is trying to sell you ENERGY STAR rated windows, you’re at least getting something nominally efficient. But for the best energy efficient windows, make sure you ask for the new R-5 standard.

Also, be wary of claims of very high R-values (e.g. R-6 to R-9) or very low U-values (U-0.18 to U-0.1) on windows. There is a good chance this measurement reflects the insulation value of the glazing itself – in other words, the manufacturer is measuring only heat transfer at the center of the pane, not the heat transfer of the entire window including the frame.

New R-5 standard for windows

While ENERGY STAR windows must have an efficiency between U-0.65 (least efficient) to U-0.35 (most efficient) depending on region, the new R-5 standard sets much more stringent requirements across the board. All R-5 windows must be – you guessed it – about R-5 or better. In fact the specification requires fixed windows to have a U-factor of U-0.2 (equivalent to R-5), but movable windows can have a slightly higher U-factor of U-0.22 or lower, which translates to R-4.54. So many movable “R-5” windows will actually be slightly below R-5. But that’s still a whole lot better than what you’ll get with a minimally qualifying ENERGY STAR window.

The other efficiency requirement for the R-5 standard has to do with air leakage. While the ENERGY STAR standard made no requirements on airflow, the R-5 specification requires manufacturers to measure airflow through the window and frame, and for that airflow to read less than 0.3 cubic feet of airflow per minute per cubic foot of window (including both the glazing and the frame).

One additional requirement of the R-5 standard that will benefit consumers is the product warranty. Qualifying windows must have at least a 20 year warranty on the glass (visibility or seal failure), and a 10 year warranty on other components (free from manufacturing defects).

R-5 windows are typically triple-pane. Note that triple pane windows from the 1970’s and 1980’s were not particularly efficient – you are probably better off replacing these with, at the very least, new double-glazed ENERGY STAR windows. These new R-5 triple-glazed windows are built using a new process that improves the quality of the seal, and features the low-E coatings that minimize unwanted heat transfer. There is at least one R-5 manufacturer who makes double-glazed R-5 windows.

A typical rule of thumb for ENERGY STAR windows is that you’ll pay about $240-250 per window. For as little as an extra $30 to $50 you can get an R-5 window instead.

There are many federal, state/provincial, local, and utility incentives and rebates available for people who install ENERGY STAR or R-5 windows. For example many municipalities and utilities in California and some in Florida offer rebates of $1 to $2.50/square foot on ENERGY STAR windows. There are often loans available to help finance purchase and installation of energy efficient windows, although the programs I reviewed had fairly high interest rates, so if you have good credit you are better off financing an upgrade with a second mortgage or line of credit loan.

Making your current windows more efficient

If you don’t want to spend a fortune on the best energy efficient windows but you still want to cut your energy losses through your windows, there are a number of less expensive things you can do to at least gain some energy efficiency.

I cover many of these concepts in my article on energy saving window coverings, where you can learn about ways to cut the convection currents around glass, how to reduce air leakage, and how some types of window coverings can add an additional layer of insulation that substantially reduces your heat loss in winter. And of course window coverings can reduce solar heat gain in hot weather by preventing sunlight from entering a room in the first place.

Other articles to consult are:

The Windows Volume Purchase program

Investing in house window replacements can be a major financial burden in the short term, although in the long term the best energy efficient windows will pay for themselves several times over. If you’re considering a major window retrofit, you may benefit from the US government’s Windows Volume Purchase program.

The Windows Volume Purchase program was established to encourage window manufacturers to produce R-5 qualified windows and offer them for sale at volume discounts. Participating manufacturers offer discounts- typically, 10 to 20% – on purchases of 15 or more windows for a retrofit, where you replace existing windows; and for purchases of 20 or more windows for a new installation.

You can take advantage of the Windows Volume Purchase program either through your own window installer (or by installing windows yourself), or by using an installer provided or recommended through one of the manufacturers participating in the program. The program provides a website that lets you select window configuration and size, and provides a list of manufacturer names, websites and phone numbers that can provide windows of that type. The program started in May 2010 and as of January 2011, about 1,000 windows have been sold with a total sales volume of about $260,000 (which should give you an idea of the typical cost of a discounted R-5 window).

This content was originally published here.

Energy-Efficient Windows: How Much Will You Really Save?

Getting energy-efficient windows for your home is widely lauded as a way to cut down on drafts and save money on heating bills … only how much do these replacement windows cost—and really save you, anyway?

To help you crunch the numbers and do some concrete cost-benefit analysis, here’s everything you need to know about adding energy-efficient windows to your home.

How energy-efficient windows work

Several elements contribute to the overall energy efficiency of windows:

Frames: If you have old windows, they are likely to have aluminum frames. The problem with that is aluminum allows hot and cold air to easily pass through from one side to the other. “A vinyl or fiberglass frame [which you’ll find in updated windows] is much more energy efficient,” says Michal Bohm, owner of BM Windows, a replacement window company in San Diego. Both of these materials are poor conductors of heat, and thus better insulation.

Number of panes: Most older windows have a single pane of glass that lets the heat of your home slip out during the winter months. (And do a similarly so-so job of keeping your air conditioning contained during the summer.) Energy-efficient windows will have two, or even three, panes to cocoon your home.

Fancy glass: In between these panes of glass, manufacturers of energy-efficient windows insert an inert gas like argon or krypton. Because these are denser than air, they reduce the amount of air that is transferred into and out of your house.

These insulated glass units (IGUs) also feature what’s known as low-emissivity (“low-e”) glass. Think of it as sunscreen for your house.

“Low-e glass features a microscopically thin layer of metallic oxides that both control infrared light and reflect the sun’s ultraviolet rays,” says Larry Patterson, franchise owner of Glass Doctor, a Neighborly Company in Dallas. “This has the combined effect of reducing solar heat gain in the summer and lowering home heat loss in the winter.”

Window installation:How your windows are installed can also make a huge difference in their performance. “You can buy the most expensive windows on the market, with the best energy- efficiency ratings, but if they aren’t installed properly, you won’t see the energy savings,” Bohm says.

Hint: When you’re ready to upgrade, think about hiring a replacement window company that has a professional installation team, rather than a company that outsources the installation to subcontractors or general laborers.

How much will energy-efficient windows save you?

The U.S. Department of Energy estimates that you’ll save between $126 to $465 a year by replacing single-pane windows in your home. Already have double-pane windows? You can still reap savings by switching them out with energy-efficient ones, but far less. Plan on $27 to $111 per year.

Where you live also matters.

“The average savings overall are about $250 in warmer states and $150 in colder states,” says David Bakke, a personal finance expert at Money Crashers.

Since the average replacement cost runs around $150 per window, depending upon how many you have to replace, you may see savings after even one year or two.

Do energy-efficient windows have other benefits?

Energy-efficient windows are also excellent at reducing noise pollution. “Most homeowners report that 60%-75% of exterior noise is muted when they installed IGUs in their home,” says Patterson.

Low-e coatings on windows also help reduce sun damage to your furniture, carpets, and even personal items like photos by up to 75%.

Plus, consider the value you could add to your home. Notes Bohm, “a conservative estimate would be to expect to recoup about 70% of the purchase price of your replacement windows when it comes time to sell your home.”

Combine that with your monthly energy savings, Bohm adds, and “your windows should more than pay for themselves.”

What are the best energy-efficient windows to buy?

Fortunately, “Manufacturers have made significant technology advancements over the years, and new labeling requirements allow you to more easily compare window performance,” says Mark Montgomery, vice president of marketing for Ply Gem Windows.

Any windows you choose should have an Energy Star rating. This means the windows will meet or exceed energy code requirements.

Next, pay attention to what’s called the National Fenestration Rating Council (NFRC) label. This lets you geek out on comparing such nitty-gritty properties as U-factor (the rate of the window’s non-solar heat loss or gain) and solar heat gain coefficient (SHGC—the fraction of solar radiation that passes through the windows). If your eyes just glazed over at that list, don’t panic.’s comprehensive Efficient Windows Collaborative can help you select the right windows based on your geography and climate.

Keep in mind, too, that many cities, states, and utility companies offer incentives or rebates for homeowners who decide to upgrade to energy-efficient windows. Ask a window company what’s available in your area, or search for current deals on

This content was originally published here.

6 Tips for Choosing Energy Efficient Windows – Inspired by Marvin

Marvin and the experts at Fine Homebuilding magazine team up to share a few smart window selection tips that can deliver long-term value.

Tip 1: Understand the Consequences of Low Quality Windows

Low-cost windows can be pricier than they first appear. Like any weak link in the building envelope, poor-performing windows require a larger HVAC system and ducting, which is pricier up front and also more costly in the long run. “With insulating values as low as U-0.18, windows can have a huge impact on a home’s energy-efficiency rating and a cascade effect on the cost of the overall project,” said Brett Dillon, a longtime builder and developer in Texas, who chairs the technical standards committee for ResNet, a nonprofit that trains and rates residential energy auditors.

The math is easy, but not all builders and homeowners respond to it. “A lot of people don’t know how much they pay for energy and don’t really care,” Dillon says. “But everyone cares about comfort.” By the time a new homeowner complains about drafty windows, or condensation, or rooms that overheat in summer, it’s too late to rip out underperforming windows. Often the builder’s or homeowner’s solution is to upgrade the entire heating and cooling system. Interestingly, complaints about draftiness can usually be traced to low-quality windows with cold glass, not air leakage, says Steve Baczek, an architect outside Boston. “People say, ‘This window feels drafty,’ but it’s really not a draft. The radiation rate of the window is too high and you feel the cold,” he says. “It’s the same reason that basements feel cool. Your body is losing heat at a much higher rate as it tries to warm the cold walls.”

Tip 2: Understand Various Window Types and Their Performance Attributes

Windows are available in a wide array of types, styles, and packages. To get the most energy efficiency and durability for your dollar, you have to break down the window into its parts. The first consideration is the type of window itself— in other words, how it functions. Dig through any manufacturer’s website and you’ll find double-hung, casement, sliding, tilt-and-turn, and so on. Mostly these are aesthetic choices based on the style of the home and outside the scope of this article, but there are two types of air seals around the window that you should know about.

Screen Shot 2017-05-24 at 10.43.17 AM.pngCasements, awnings, and tilt-and-turns all swing outward or inward, and when locked, they are pushed or pulled tightly against their weatherstripping. From an energy-efficiency standpoint, their compression seals give those windows a distinct advantage over windows that slide, either sideways or vertically (such as single- and double-hungs). So if you’ve been dead set on double-hungs, you might want to consider adding some windows that swing instead of slide. You’ll get better insulation, with all other things being equal.

Texas builder Matt Risinger agrees: “Get as many awning or casement windows as you can. They seal better, and their screens are on the inside, so they stay cleaner and are easier to take off in winter.”

Tip 3: Choose the Right Frame Material

After basic functionality, the choice of frame material has the greatest impact on price and performance. Frame materials are generally the weak link in a window’s thermal performance, and at 15% to 20% of the overall surface, the frame has a big impact on U-Factor. But there is also durability and weatherability to consider. The longevity of window frames, claddings, and finishes varies widely. Selecting the appropriate windows based on the environment is critical, especially in regions with extreme weather.

For example – fiberglass windows, whether they’re made completely of fiberglass or clad, have superior weatherization and insulation properties when compared to alternative materials. This makes them ideally suited for homes built in harsh locations and in homes that are taking energy efficiency seriously.  With its very low conductivity, fiberglass is also the best insulator among window-frame materials. And it shrinks and expands at the same rate as glass, making its air-seals as durable as the rest of the unit. Its longterm stability also ensures that fiberglass windows will operate like new for decades to come.

Tip 4: Understand EnergyStar Recommendations

Energy Star recommendations are given for four climate zones in the United States: the mostly heating zone (Northern); two combination heating and cooling zones (North/Central and South/Central); and a mostly cooling zone (Southern). Every qualified window will list the zones it is certified for. The Energy Star standard is a good benchmark for energy-conscious architects and builders, but every house is unique. To choose the best-performing windows, it’s still recommended to work with a supplier to take into account factors such as site orientation and the size and number of windows.

Tip 5: Select the Right Glazing Package

The glass, called glazing, is the other critical component in your window package. While manufacturers tend to pick a frame material and stick with it, they offer a wide range of glass configurations and coatings, all of which have a big impact on energy efficiency. In fact, the top U.S. window manufacturers get their glass from just a few factories, who specialize in combining the high-tech coatings, films, spacers, and gases that go into today’s glazing units.

Two-pane insulated units are now standard, and that step alone has greatly reduced the U-Factor, or the amount of heat a window lets through. Adding inexpensive low-e coatings and argon gas between the panes can take a two-pane window up to a U-Factor of 0.3, which will meet the Energy Star standards for all regions.

The next big step up is adding a third pane, which can lower the window’s overall U-Factor by another 50 percent. Some designers and builders of low-energy homes have relied on European triple-pane windows as part of a superinsulated building envelope. However, these window packages are traditionally cost-prohibitive for many clients. Double-pane windows and domestic triple-pane units can offer performance at less expense. Still, experts advise finding more cost-effective ways to improve a building’s thermal envelope before going to three-pane units.

“As we start building more airtight and insulated homes, triple-glazed will start to make more sense,” Risinger predicts. “Here, we aren’t quite there yet.”

Tip 6: There is no Label for “Durability”

The National Fenestration Ratings Council provides a label on every window that gives reliable numbers for its energy-efficiency. But performance, comfort, and overall value aren’t just about initial energy-efficiency. If windows aren’t strong and durable, that performance won’t last. Windows can even become a nuisance. “There’s nothing worse than busting your butt all day at work and then coming home to find sticking windows, rotting siding, and more stuff to fix,” Dillon says. “It’s a big reason why more people are renting.” Choosing windows that will save energy, stand up to the weather, and perform like new for decades might seem like a lofty goal, but today’s technologies put it well within reach.

This content originally appeared in Fine Homebuilding magazine.

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Glare from energy-efficient windows can melt siding, vehicles ::

Apex, N.C. — Energy-efficient windows make up more than 90 percent of all new window installations in the U.S., according to a survey by the National Association of Home Builders. But they can become problematic for homeowners when sunlight bounces off the windows and is so intense that it can melt siding on houses and parts of vehicles.

Weeks after moving into a new home in Apex in December, Michelle Curtis noticed that plastic parts of her SUV had bubbled and melted.

“It was pretty unbelievable,” she said. “It’s like, could this really be happening? Could the reflection of the sun on a window of a house do this kind of damage to a vehicle?”

Experts say it is possible. The windows, which use low-emissivity glass, can act like a magnifying glass and reflect the sun’s rays. Clear glass reflects about 10 percent of sunlight’s energy, but low-e windows, which have a green tint, reflect 30 to 50 percent, according to NAHB.

Low-e windows are generally mandated by modern building and energy codes for new construction.

“Low-e window glass is coated with a thin layer of metal or metallic oxide. Visible light is passed through low-e windows without difficulty, but the metallic layer blocks the passage of heat inducing ultraviolet light into the home, reflecting that light outward,” David Crump, NAHB director of construction liability and legal research, wrote. “This keeps the home cooler in summer. In the winter, the effect is reversed, with interior heat blocked from passing outward.”

Reports show the coating used on the windows to reflect the sun, combined with a concave effect in some windows, magnifies and intensifies the beam up to 200 degrees Fahrenheit. The problem is worse in late fall, winter and early spring due to the low angle of the sun.

Problems with low-e windows have been reported across the country. The beams have melted vinyl siding, plastic and paneling on cars and garbage cans. Reflections from the windows burned people at a pool at the Vdara hotel, a high-rise in Las Vegas. The windows on a London skyscraper were blamed for melting part of a Jaguar XJ. The Consumer Product Safety Commission said beams from sunroom roofs have started fires on cedar shingles in at least four homes.

“I just hate telling people that we can’t help, and in this case, we haven’t figured out how to help,” he said. “It’s just the collision of technology. It’s a problem, and there’s not an easy solution to it.”

Tingen says window manufacturers have “done exactly what we asked them to do” by creating high-efficiency windows, but the new technology “has created an unintended consequence.”

That consequence caused siding manufacturers to take the extra step of changing their warranties to exclude damage from external heat sources, including low-e windows. Homeowners who complain can have a hard time finding someone to take the blame.

In Curtis’ case, she contacted her builder, the window manufacturer and her car and homeowner’s insurance about the damage done to her SUV.

“No one’s taking responsibility. They’re (saying), ‘Contact this person. See what he says. Contact this other person,’ and (I’m) kind of getting the runaround,” she said. “If anything, we should be warned that this can happen. There should be some kind of safety warning. We certainly wouldn’t have parked our vehicles here if we had any kind of warning.”

After 5 On Your Side got involved, Curtis’ builder offered to replace the low-e windows in question with regular glass. Although it doesn’t meet code, many industry experts say it’s the best solution for now. Other options could include adding screens or shrubbery to diffuse the beam.

For homeowners who are worried that their low-e windows might damage their neighbors’ property, legal experts say they should switch to regular glass, which costs about $150.

This content was originally published here.

How Much Do Replacement Windows Cost in Omaha?

Windows represent a crucial aspect of any home. If you are looking to make your house more beautiful, more energy efficient, and secure, replacement windows are the way to go. A single investment can provide all three benefits at the same time.

Replacing your existing windows with today’s more modern and energy efficient windows will allow more natural light to shine through and lower your monthly energy bill by a significant margin. It means that they will pay for themselves over the long-term. They’re also much more secure than older models, so any intruders will have a much harder time entering your home.

And as far as aesthetics are concerned, there are numerous window styles, shapes, and sizes to choose from, like single hung or double hung windows, casement windows, sliding windows, pane windows, awning windows, picture windows, bay windows, and the list can go on. Depending on your needs, taste, and, of course, budget, you can turn your home into a charming and energy-efficient “fortress” with a single home renovation project.

How Much Do Replacement Windows Cost the US?

On a national average, the cost of a single replacement window is around $600. It can range from an average minimum of about $300 and can reach as high as $1,000 per window. These figures depend on the total number and the types of windows installed, local costs, etc.

When it comes to replacing a standard, double hung window, for instance, costs vary between $300 and $750. It will also include the labor costs if the window fits in the old window frame that’s in good shape. For a 3-bedroom home with ten windows, prices can range between $2,500 and $7,500.

Keep in mind that these are only averages taken on a national level. The real costs can vary based on your local area, as well as several other factors such as:

  • The total number of replacement windows.
  • The types of windows used.
  • Window frames, styles, and other adjacent materials
  • Type of insulation needed.
  • Local installation costs.
  • The standard price for windows in your area

How Much Do Replacement Windows Cost in Omaha, NE?

Now that we know how much windows cost nationally, we can focus on window replacement costs in Omaha. It is highly recommended to learn the values before starting the replacement project. National averages will help give a general idea, but with informing yourself about Omaha’s material costs, labor rates, local permits, etc., it will help you form a more in-depth picture of what to expect going forward.

As of 2019, homeowners in Douglas County paid on average between $355.00 and $475.00 per replacement window. It included the material costs, average labor costs to install replacement windows, the average prices of extra materials and equipment, as well as any additional project costs such as surface preparation, machinery, components, and cleanup fees.

Depending on various cases and circumstances, there may be additional costs that go into a window replacement project. These include special permits for window replacement, inspection or building fees, other sales taxes on materials and supply in Omaha, Douglas County, or the State of Nebraska. The average contractor fees will add a further $49.80 to $62.25 to the total.

But keep in mind that no one offers better and more affordable windows in Omaha, NE than 1-800-HANSONS. Call us today to get expert help from one of our experienced professionals, or request a free estimate here.

Evaluating Energy Efficient Windows

Evaluating Energy Efficient Windows

Many Houston Texas homeowners would like to know more about the energy efficiency of their windows. Most of the new replacement windows are labeled to indicate their energy properties but this information may not be available on existing or older windows. Below is an energy efficiency checklist to help you with the process of determining the energy efficiency of your home windows.

The Energy Star Label

First try looking for products that have earned the Energy Star label. The Energy Star label indicates that the window meets energy performance recommendations set by the US Department of Energy. The label includes a map of where the specific window qualifies for the specific climate zone. Windows that are Energy Star qualified should typically meet or exceed energy code requirements for your area. The determining factors for qualification criteria for Energy Star windows is based on your the climate and location of your home.

The NFRC Window Ratings Label

Check for window ratings and energy efficient properties on the NFRC Window Ratings Label. The National Fenestration Rating Council (NFRC) label is needed for verification of energy code compliance. The NFRC label displays whole-window energy properties and appears on all products in the ENERGY STAR program providing a reliable way to determine the window’s energy efficiency properties.

NFRC Energy Star Label Example Houston Texas Home Exteriors

NFRC Energy Star Label Example – The Energy Star label indicates that the window meets energy performance recommendations set by the US Department of Energy. The label includes a map of where the specific window qualifies for the specific climate zone.

Window Performance

Check the windows for any energy performance labels and information on window performance. If there are no labels or you cannot find any information on the window, you can visually inspect the window to determine the assumed window energy performance with the following:

1 – Verify how many panes of glass the windows has, with each pane of glass comes additional energy efficiency

2 – What material is the window frame made from (aluminum, wood, vinyl).  Windows made with wood or vinyl frames insulate better than metal-framed window options so are more energy efficient.

Below are charts to help in assuming the U-factor and solar heat gain coefficient (SHGC).  The U-factor is a measure of non-solar heat transfer (like heat escaping in the winter). A lower U-factor is better (lower means less heat loss). The SHGC indicates how much heat from the sun enters through a window. A low SHGC is more important in the hotter climates like the Houston Texas area. The U-factor and SHGC of a window are shown on the NFRC label. Energy Star windows meet the recommended values shown here:

Window Energy Star Climate Zone Map Houston Texas Home Exteriors 281-919-6999

Energy Star Window Climate Zone Map

Window U-factor SHGC Energy Star Recommended Values for Climate Houston Texas Home Exteriors

The U-factor and SHGC of a window are shown on the NFRC label. The U-factor is a measure of non-solar heat transfer. A lower U-factor is better, lower means less heat loss. The SHGC indicates how much heat from the sun enters through a window. A low SHGC is more important in the hotter climates like the Houston Texas area.

Below is a chart you can reference using the information collected above for the assumed U-factor and SHGC values. This information is based on the International Energy Conservation Code and does not account for features you may not be able to verify such as low-E coatings, gas fills, etc).

U-factor SHGC Approximate Chart Houston Texas

U-factor SHGC Approximation Chart (These values are based on the International Energy Conservation Code and do not take into account features that you may not be able to verify such as low-E coatings, gas fills, etc.)

3 – Does the window glass has low-E coatings? Low-E coatings are invisible heat barriers that improve window energy efficiency. The most reliable way to identify these coatings is to use a low-E detector device (equipment energy auditors may use). Chances are you do not own one of these but you may be able to identify low-E glass by using a lighter flame or white card by holding either up to the glass and looking for the two reflections from each pane of glass. If one of the panes looks bluer than the other, this is an indication of a low-E coating on that surface.

4 – Does the window have an airtight fit and weatherstripping. Check the sashes and weatherstripping as these are important factors. The windows may have air leakage if they are not fitted tightly or air could be leaking from in between the interface of the frame and the wall if they were not properly sealed during installation. This may be difficult to check for on existing windows.

Professional Window Installation

If you are ready to replace your windows, remember the importance of proper installation of your new energy efficient Energy Star rated windows. This is most necessary for optimal performance of energy efficient windows, to ensuring there is an airtight fit and to avoid water leakage. Use experienced professionals for your window selection and installation.

Additionally, check the Department of Energy for info replacing windows with energy efficient windows that are Energy Star rated.

Don’t forget to subscribe to our blog and feel free to call me at Texas Home Exteriors, we are here to assist you in your replacement window selection and installation of new energy efficient windows in the Houston, Spring, The Woodlands metro area. We offer a variety of options, call us today at 281.919.6999 and visit our website click her Texas Home Exteriors.  Be sure to check out our Texas Home Exclusive Windows made for the Houston Texas Climate!

Free Energy Star Window Estimate

Energy efficient windows savings

DAYTON, Ohio (WDTN)  A good working furnace isn’t the only factor in making sure your home stays warm in the winter.

Energy efficient windows can help reduce drafts and save you money on your heating bill.

No matter what the weather is outside – the goal is to make sure you’re always comfortable inside your home. Energy efficient windows can be a big bonus all year long.

“The new windows are actually heat reflective so they’ll work all year round. they’ll reflect the heat from your furnace back into the interior of your home and in the summer they’ll reflect the warm air from the sun,” Walt Knisley All Seal Sales Manager explains.

In order to see how much energy is saved with new windows, Walt Knisley with All Seal uses this meter to measure how much heat gets through each pane.

“Now this is one of our higher efficiency glass units, again it’s a double pane glass, 10, it drops it down to 10 percent. The heat is coming back it’s not passing through the glass,” Knisley explains.

While it may seem like you would want the heat pass through during the winter the sun angle is so low it really doesn’t benefit you that much.

When talking about energy efficiency it’s not only about windows but doors too. If your door is old it could have warped over time. and that can create heat loss.

“A lot of the times 30 to 40 year old doors the jams are slightly warped and makes them more difficult to open and close,” Knisley says.

While new doors and windows may be costly upfront according to energy star dot gov you could see a 9 to 22 percent savings per year. Which would save money and energy in the long run.

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How to Pick the Most Energy-Efficient Windows and Doors

Visually stunning windows and doors are a cornerstone of thoughtful modern design, and they can dramatically change the way a home appears from the outside – as well as how it is experienced on the inside. Beyond aesthetics, choosing door and window products that are functionally efficient is just as important, so that lasting benefits can be enjoyed for years to come. In addition to ultra-contemporary styling, Western Window Systems boasts recognized energy efficiency and sustainability standards.

Modern windows, often aluminum, are not always energy efficient, despite frequent assumption. Aluminum, by nature, is a strong conductor of heat, so the anatomy of the window itself is critical to determining energy efficiency. The fenestration industry has seen substantial innovation in recent years, which has allowed dramatic advancements in aluminum window and door technology.

Before choosing energy efficient windows, it is important to understand what requirements may be dictated by your local state or region. The International Energy Conservation Code (IECC) is the most commonly used energy code for residential buildings. Rather than acting as a comprehensive compliance tool, the code establishes “minimum standards” that have been adopted in many regions across the United States. Beyond this baseline, many states have more stringent local requirements that should be taken into account to ensure compliance in your specific region.

This net-zero residence by CitiZen Design Studio features Western Window Systems chosen for energy efficiency. The Series 600 Multi-Slide 90-Degree Door is architecturally eye-catching, meeting at a right angle in the home’s great room, and features dual-paned low-E glass.

Once individual requirements are identified, doors and windows that meet unique project needs can be selected. Whether a homeowner, architect, or builder, it is always a delicate balance to select doors and windows that fit a project’s aesthetics, while also standing up to rigorous energy efficiency requirements. Products from Western Window Systems are tested and certified by the National Fenestration Rating Council (NFRC), an organization providing independent and accurate energy performance ratings for door and window products.

Many Western Window Systems products with aluminum frames offer the option of thermally broken aluminum for maximum energy efficiency. Being a strong conductor of heat, standard aluminum allows a significant amount of energy to be gained or lost through the frame itself. Western Window Systems adds a thermal break within the aluminum frame, creating a gap between the outside and inside of the home and substantially reducing conduction and increasing energy efficiency.

In additional to thermally broken aluminum frames, all Western Window Systems products also feature dual-paned, triple-coated low-E glass. In contrast to standard clear glass, glass with low emissivity (low-E) coatings reflect long-wave infrared radiation away from the surface, rather than absorbing it. This means that heat transfer between outside and inside is minimized, and homes can stay better insulated in any climate. Western Window Systems door systems also include low-profile weatherstripping at points of closure. These tight, durable seals help control humidity and moisture, and minimize air leakage.

Tucson’s Courtyard House, by HK Associates, features giant floor-to-ceiling fixed windows from Western Window Systems, and Series 600 Sliding Doors. Optional thermally broken aluminum frames increase energy efficiency.

Western Window Systems Pivot Doors feature dual-paned low-E glass.

How to Pick the Most Energy-Efficient Windows and Doors – Photo 4 of 5 – In ARCHITECTUREFIRM’s James River House, the 28-foot-long Series 600 Multi-Slide door is comprised of five 10-foot-tall panels of dual-paned, low-E glass, which helps keep the house warm during Virginia winters. All windows and doors feature thermally broken aluminum. “Western Window Systems,” says architect Danny MacNelly, “does a great aluminum product that isn’t very expensive. The details are minimal, clean, and refined.”

In ARCHITECTUREFIRM’s James River House, the 28-foot-long Series 600 Multi-Slide door is comprised of five 10-foot-tall panels of dual-paned, low-E glass, which helps keep the house warm during Virginia winters. All windows and doors feature thermally broken aluminum. “Western Window Systems,” says architect Danny MacNelly, “does a great aluminum product that isn’t very expensive. The details are minimal, clean, and refined.”

Western Window Systems’ newest family of products, the Series 7000 line, is the company’s strongest and most energy efficient design to date. Beyond offering countless size and customization options, the Series 7000’s high-performance aluminum doors boast low-E, argon-filled dual-pane glass, and a standard 0.30 U-Factor. U-Factor, a recognized rating method by the NFRC, measures the heat from inside a room that can escape. When selecting energy efficient doors and windows, lower U-Factors reflect higher energy performance – the lower the number, the lower the potential for wasted heating expenses.

How to Pick the Most Energy-Efficient Windows and Doors – Photo 5 of 5 – The Series 7600 Multi-Slide Door is Western Window Systems’ most energy efficient design to date.

The Series 7600 Multi-Slide Door is Western Window Systems’ most energy efficient design to date.

Whether designing a new home, or simply upgrading old windows, choosing energy efficient products with recognized quality and performance will help ensure doors and windows resiliently and beautifully stand the test of time.

The benefits of energy efficient windows and doors – A Very Cozy Home

The benefits of energy efficient windows and doors

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Your home is your castle, but it also an infrastructure project that needs to be maintained with regular updates and upgrades. When you look at your home, you need to see it as a source of comfort, but also as an expensive proposition if you aren’t keeping up with regular updates. Single pane windows and old doors that aren’t sealed or lack insulation are the biggest sources of heat leaks that can be inflicted upon your home. If money up in smoke is of no concern to you or your carbon footprint growing then replacing your windows and doors won’t be part of your home’s maintenance package. If you value the money you spend heating and cooling your home, replacing old windows and doors with new, energy-efficient windows and doors, contact us at AM Window and Door Solutions. We have the expertise and experience to retrofit your home with quality products that will reduce your energy consumption and improve the quality of life in your home.

Develop your strategy with AM Window and Door Solutions

For your windows and doors solution that provides energy efficiency and improved quality of life, AM Window and Door Solutions is the only company to select. We are a three-generation company that has over 60-years of service to the industry. Our installers are licensed and insured to protect a homeowner and our 10-year warranty for labour is by far the longest in our business. The materials we install will come with a manufacturer’s warranty that you can count on if there are problems in the future.

At AM Window and Door Solutions, our experts are ready to help you chart a course to energy efficiency through the installation of new windows and doors. For a consultation that comes with a free estimate, please contact us at AM Window and Door Solutions today at 1.877.281.6900.