Is Double-Glazing Worth it?

Your home’s single-glazed windows let heat in during summer and out during winter. This is the opposite of what you want. It costs money to warm or cool your house to tackle this. Double-glazing your windows can save you up to 30% on your energy bills through cutting household energy consumption. Calculate that over ten or twenty years, and you can see how worthwhile it is to invest in double-glazed windows.

In this article, we’ll show you why double-glazed windows are a smart investment for your home, explaining how they save you money while keeping your home cooler in summer and warmer in winter.

What are Double-Glazed Windows?

A double-glazed window consists of two panes of glass with a noble gas, such as argon, sandwiched between them. This gas slows down heat transmission, helping to keep your home cooler in summer and warmer in winter.

Double-glazed windows are sealed to prevent gas leakage and are framed with uPVC, which enhances insulation and prevents heat from escaping through gaps between the window pane and your home.

Not only do double-glazed windows offer a stylish balance between decor and energy efficiency, but they also enhance your home’s value. They provide a smart investment by reducing energy bills and contributing to your home’s long-term value.

How Much Can I Save With Double-Glazing?

You can save money on the installation of your double-glazed windows, thanks to the Victorian government. And you save money on your energy bills every year, to the tune of around $300. This savings can be increased by closing curtains during summer, having a fully insulated home, and smart use of your heater and air conditioning.

The first way you can save money with double-glazed windows is through discounts thanks to the Victorian government. Owners of investment properties, and home owners directly, are eligible for discounts if their home has only single-glazed windows. The discount you can expect are indicated in this table, thanks to the Victoria Energy website:

The second, and most notable way double-glazed windows save you money is through improved efficiency. By insulating your home, they help keep it cooler in summer and warmer in winter. This allows you to use your heating and cooling systems more efficiently, reducing the cost of maintaining a comfortable temperature throughout the year.

Double-glazed windows can retain upwards of 30% more heat or coolness than single-glazed windows. This can translate to upwards of a $300 per year saving on your energy bills.

This saving on your bills can be improved by a few other factors. If you have insulation in your roof, or the orientation of your house reduces direct sunlight onto your windows, then the energy savings can creep upwards. Humidity would lower the savings on your energy bills, however. Air conditioning works by removing humidity from the air, and has to work harder in humid climates.

You may not have a say on the orientation of your home, but you can make a choice about your windows. There is a proactive way you can save money and lower your energy bills, and carbon footprint, by installing double-glazed windows.

How Do Double-Glazing Windows Save Heat Energy?

It’s amazing that just a window can save you money, save you heat energy. For the science minded, there are the three factors determining the efficiency of double-glazed windows and why they are worth it. They are the solar heat gain coefficient for windows (SHGC), the conduction factor for windows (U), and the visible light transmittance for windows (VLT)

Solar Heat Gain Coefficient for Windows.

The SHGC is the fraction of the sun’s rays which strikes the glass and enters a room. If 600W of solar energy strikes a pane of glass and only 200W entered the room, then the SHGC of that pane of glass would be – 200/600 = 0.333. It is measured in a range from 0 to 1. In summer a smaller SHGC is better, while in winter a higher one is preferred.

U Value

U value is a measure of heat energy which is conducted through your window, measured in watts. The formula to work this value out is Uw x T x A = W, where T is the difference between inside and outside air temperature, A is the area of glass, and W is the measurement in watts.

The lower the U value the greater a window’s resistance to heat, and the better it is at insulating your home. The lower the U value the lower the heat loss and the more you can save on your heating bills in winter.

Visible Light Transmittance

VLT is the fraction of visible light making it through the window, how well-lit your room is thanks to the windows. It is expressed in a number from 0 (no light getting through), to 1 (all possible light is getting through)

A low VLT can reduce heat gain from outside, but it also might make the inside of your home a little dark.

Here is a table that gives you these measurements and some window types they apply to:

Energy performance of common window types

Double-Glazed v Single-Glazed

Single-glazed windows are what you see everywhere. They are easy to make, easy to install and don’t cost much money, relatively speaking. There is a reason they are less expensive than double-glazed windows. They are at least 20% less insolation than an insulated wall if they’re installed. This means they easily let heat into your home in summer, or they let heat rush out during winter.

There is leakage in other ways with single-paned glass as well, through draughts thanks to poor sealing or cracks. And they’re not very secure either. Breaking a single pane of glass is much easier to do than a double-glazed window.

In a community that is growing ever more conscious of saving money and being environmentally friendly, single-glazed windows are surely on the way out.

Double-glazed windows are winners when it comes to energy efficiency. With argon gas between the two panes of glass, heat energy finds it difficult to excite the argon atoms, and so the transfer of heat energy drops significantly.

You also have significant sound proofing with double-glazed windows. In the same way with heat energy, soundwaves get blocked by two panes of glass and the argon gas. This is great if you live on a main road, or near a school or sporting ground. The reduction in potential stress is wonderful.

What are the benefits and disadvantages?

We go into much more detail about the advantages of double-glazed windows here, however we can’t talk about double-glazed windows being worth it without mentioning in brief the upsides and downsides.

ADVANTAGES

1. They help you save on energy bills. By lowering heat loss in winter and heat gain in summer, you use your heating and cooling less, which saves money on your energy bills.
2. Double-glazing boosts the soundproofing of your home. The two panes of glass and argon gas are excellent at stopping soundwaves from coming through the glass, making your home much more peaceful and quiet.
3. They improve your security. It is much more difficult to break and enter through double-glazed windows than single-pane, increasing your security and peace of mind.

DISADVANTAGES

1. Double- glazed windows and doors can trap heat. While trapping heat in winter is good, it’s not so good in summer. Despite the best insulation there is, a very hot day in summer can still warm up your home, and double-glazed windows will bottle that heat.
2. Double-glazed windows cannot be repaired. If you break one of our double-glazed windows, you can’t simply repair it. The argon gas would have escaped and the integrity of the window would have been compromised.
3. Double-glazing can cost more initially. Yes, double-glazed windows cost more than single-glazed windows, however the savings over time absolutely justify the investment.

The long term savings you achieve with double-glazed windows cannot be underestimated. Everyday you hear stories of how the cost of living is crunching hard, so finding ways to save pennies, and help the planet, is a good thing. Contact us today to learn more about double-glazing windows.