Energy bills have been going up year on year. It’s expected that next year, the cost of electricity will increase by nearly 3 percent. In an economic environment still struggling from the effects of the Coronavirus pandemic, increases in costs are majorly affecting households.
Double glazed windows are an excellent way to reduce your energy costs. This is because the windows are cleverly designed to act as an insulator.
In this article, we will explain some of the science behind how this insulation works and how it leads to multiple benefits, not just saving on your energy bills.
We will also help you to understand the performance ratings of windows and how that can help you decide if they’re worth the investment.
Double Glazed Windows — IGU
IGU is an acronym for ‘Insulated Glass Unit.’ Most people know that double glazing involves putting two panes of glass together.
However, few know that the gap between the glass is as important as the glass itself.
The gap is filled with a gas, most often being argon. This fascinating gas has a multitude of applications including being used in fluorescent light tubes.
Its application to double glazing is that it’s denser than air and therefore adds to the insulation.
The double glazed window should be viewed as a whole and so consists of the glass, the gas, and seals. Within the gap is also a piece called the spacer which defines the size of the gap between the glass panes. The spacer also contains a special substance called a desiccant.
You will have seen this type of material in small sachets used in packing some goods. Its purpose is to absorb any moisture in the immediate vicinity. For this reason, it is part of the spacer in your window so as to reduce any moisture penetration.
Everything to Gain
The following are some of the many benefits that come from having double glazed windows in your home. All of these benefits come from the fact there’s a layer of gas between the glass panes.
Heat does not transfer efficiently from air to glass, and then through the gas and back to glass again. The double glazed window offers a sort of resistance to the passage of heat through it. That means the heat in your home is trapped inside your home for longer.
Your heating system will work less to maintain a constant temperature. That saves you money on your heating bill. The wonderful thing about double glazing is that this characteristic is also true during the summer.
That means that cool air also, will not pass through the glass efficiently and is trapped within your home. So, during the summer, your air conditioning bill will also be less.
Another major gain when using double glazing is the acoustic benefits. Similar principles that govern the transfer of heat also govern the transfer of sound. In fact, it’s the complex physics of impedance that serves to insulate your home from outside noise.
The gist of it is that as sound passes through different mediums, the impedances of these mediums aren’t the same. They are mismatched. The result is that sound energy is lost.
This means outside sounds cannot penetrate your double glazed windows as easily as just single glazing. The reverse is also true so that sound coming from within your home is also kept within the privacy of your own home.
Insulate Not Condensate
Condensation occurs when there is a temperature differential between 2 surfaces. For example, when you get in your car on a cold day and turn on the heat in the car you’ll see that the windows tend to steam up.
This is because the warm air is coming into contact with the cold glass and moisture in the air then condensates on the glass as a result.
This same problem happens when you have single glazing in your home. Condensation then runs down into the window frame and can cause even more problems.
Double glazing helps prevent this by separating the outer surface layer of glass from the inner surface layer of glass.
This allows the inner layer of glass to warm up with the ambient room temperature while still being insulated from the cold outer layer by the body of gas between them.
Safe and Secure
Another excellent benefit of double glazed windows is that they are secure. They are an excellent deterrent to someone breaking into your home. Trying to break a double glazed window is much harder than single glazing.
The structural design of the window is much more robust and resistant to breakage. Plus you can have safety glass fitted which is even stronger and resistant to breaking.
Single glazed windows tend to have older frames that are worn and much more vulnerable to break-in, so double glazing is an excellent option to help beef up the security of your home.
Know Your Variables
It is possible to configure the different parameters that govern your double glazed window so that you can enhance various performance aspects of the window.
The standard gap between 2 panes of glass is about 10 mm. However, the size of this space can be increased to as much as 150 mm or more.
The advantage is that the window becomes more acoustically insulated. This is especially beneficial for reducing the transmission of low-frequency sounds, that has a longer wavelength, through the glass.
That said, the increase in space reduces the heat-insulating properties of the glass. Better heat insulation occurs around 10-20mm. So it’s possible to customize the windows by balancing out what your performance needs are.
The type of glass you use also makes a big difference. For example, you can use standard glass or special glass that’s coated with a thin membrane that filters UV light. This is called low emissivity glass or Low-e glass.
The result of this type of glass is that the heat insulating ability of the glass is even further improved. So whether you use this type of glass or the standard form depends on your budget and what your primary reason is for fitting double glazing.
Follow the Ratings
It is helpful to know that double glazed windows are independently assessed for their performance and energy ratings. Look out for these measures.
This is a measure of the window’s ability to resist heat transfer through it. The lower the number the better the window is at reflecting heat into the room.
Solar Heat Gain Coefficient
This is an indication of how the glass heats up from the sun. The lower the number, the cooler your room will be during the summer.
This indicates how well natural light can pass through the glass and light up the inside room. The higher the number, the brighter your room, and the less you will need to spend on electrical lighting.
This is what it says on the tin. It’s an indication of how much air can pass through the window unit and into your house.
Cost and Reward
As you have read in this article, there are somethings that double glazed windows offer that single glazed windows cannot.
You need to weigh up not only the cost of windows but the added benefits they bring to the quality and comfort of your home life. It’s hard to quantify that with a number.
That said you can make some basic calculations. For example, the average lifespan of double glazed windows is about 20 to 30 years depending on where you live and how well you look after your windows.
Before you invest in your new windows you should divide the quoted price over the lifetime period of the windows. This will at least give you the annual cost of your windows offset by any energy savings.
Of course, these days, if you’re selling your home and you don’t have double glazing windows already fitted, then that could slow down a potential sale. So there are more factors involved here than just cost. Check out the windows Raleigh Durham install as excellent examples of what is available.
Double Glazed Windows — Smashed It
In this article, you have learned about how double glazed windows work and what some of the science is that leads to the benefits of an insulated window.
Depending on where you live, the weather variations, the noise levels outside, and so forth, these types of windows can make a big difference to your home.
Is it worth it or not? That’s a question only you can answer, but one thing is for sure. The popularity of this type of window is going to continue in one direction.
Check out some of the other latest posts on our site that will continue to keep you inspired about improving your home.