Energy Efficient Glass Windows: Everything You Need to Know

Glass windows room with chair and couch

By reducing the sun’s glare in the warmer months and helping to heat the interior during winter, energy efficient glass will assist you in maximising energy efficiency. Around 8 percent of a house’s exterior consists of glass, so it’s easy to see why it plays an important role in energy efficiency.

What to Know when Choosing Energy Efficient Glass

The heat gain in winter is massive with a 91 percent gain using an efficient glass, particularly with double glazing. The loss of heat during the winter can be attributable to glass, with as much as 60 percent heat likely to be lost if you’re not using energy efficient glass.

You can halve this with the use of more efficient glass such as Low E glass, which can contribute to improved comfort within the home and lower electricity bills.

The varying thickness of glass will determine the levels of energy efficiency. You can look at the Australian Window Association (AWA) rating structure called WERS. Under this structure, double glazing outperforms all other types of glass with its ability to insulate heat gain and loss between the exterior/interior environments, while negating the transfer of radiation and light through the glass.

Although double glazing is considered the highest performer of all the glass options available, it’s important to understand your choices and what’s available out there on the market.

Types of Glass and their Benefits

Float Glass

Float glass is the more common glass you will find in homes. Performance wise, it’s a poor cousin of other types of energy efficient glass and is also considered a weak alternative. Float glass is more prone to shattering, and an impractical option if energy efficiency is the primary reason for installation. If you want to see a reduction in your energy bills while increasing the comfort of your environment all year round, float glass isn’t the option for you.

Tinted Glass

When you hear someone talking about ‘tinted glass’ you’re likely to assume that this is a high performer inefficiency. Well, actually it doesn’t rank far above float glass. This somewhat inefficient performer for conserving energy is more applicable to wet areas such as shower screens; your car windows and oven doors.

Toughened Glass

Toughened glass is what the name suggests. It’s around 5 times stronger than float glass and designed to withstand hard knocks. Although it is suited to homes and commercial property alike, it is an unrealistic expectation to assume you’ll get the added benefit of the energy conserving properties you’re looking for.  This glass is more about preserving your security.

Laminated Glass

Moving up the scale, laminated glass is capable of doubling your energy efficiency with its ‘A’ grade safety glass, and is proven effective in reducing UV radiation while acting as a superior heat insulator. Laminated glass is suited to all externally fitted windows, and will easily accommodate the energy efficiency that you’re searching for. But keep in mind, laminated glass isn’t particularly suited to a low budget.

Low E Glass

Another energy efficient glass is the Low E glass. This glass reflects rather than absorbs the sun’s radiation, improving the overall comfort of your home. The glass is more suited to higher budgets, but the benefits of spending those extra dollars will equate to a reduction in your energy bill for years to come. This glass keeps your rooms cooler in summer and warmer in winter and is well worth considering.

Double Glazing

Double Glazing is considered the highest performing energy efficient glass on the current market. It’s also stronger and can be customized for any application, making this an appealing option to most. It comes in normal, toughened and laminated glass, as well as the popular Low E glass. Double glazed windows can be fitted to both residential and commercial buildings, and as a bonus, can also assist in noise reduction in high noise areas. Again, this glass is not suited to those with a low budget, and using this type of glass in an older home may result in a reduction of its normally high energy efficient qualities.

About the Author

Nathan Bishop is the owner of Go Green Glazing. They are an Australian business based in Geelong that specialises in the retrofit of double glazed windows. His team has over 100 years of combined experience in window repair, replacement & retrofitting.

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