Double Vs Single Glazing

Double glazing is proven to be more energy efficient than single glazing which explains its popularity over recent years when renovating or building a new home. However, there are a myriad of reasons that people choose double glazing over single glazing. In this article we explain what glazing is and the key differences between double and single glazing that can help you decide which is the right one for you.

What is Glazing?

Glazing refers to the glass itself that is installed in the window or door frame. The glass used in the window or door frames, can be single glazed, double glazed, triple glazed, laminated, tempered or low E glass. The type of glazing makes a significant difference to thermal efficiency.

What is Double Glazing?

As the name suggests, double glazing is when two panes of glass are used in a window or door frame instead of one, with a 6mm-12mm air gap filled with argon gas between the panes. Double glazed windows have an external pane of glass which is the first layer of protection. It then has an air gap of 6mm-12mm filled with argon gas to act as an insulator, and finally an internal pane of glass that fully seals the window.

What is Single Glazing?

Single glazing refers to when one pane of glass is used inside a window or door frame. The single piece of glass usually measures between 3mm and 12mm in thickness. The glass is set into a frame using glazing putty and nails. Single glazing was originally used for windows and doors in the construction of buildings for many years. Historically it has been the go to choice for windows until modern technology and advancements created more energy efficient double and triple glazing.

Advantages and Disadvantages of Double Glazing Vs Single Glazing

For those contemplating whether to install double-glazed or single-glazed windows, it is important to know the advantages and disadvantages of the two. The type of windows you choose will have an impact on the home’s energy efficiency, bills, and noise levels. Here are the advantages and disadvantages of both double glazing and single glazing.

Advantages of Double Glazing

• Energy efficiency: Double glazing provides better insulation and less heat transfer which improves energy efficiency. Double glazed windows improves the home’s energy efficiency rating by about 30%.
• Reduced energy bills: Double glazed windows retain up to 30% more heat and air conditioned air than single glazed windows which means it takes less energy to warm or cool a home. Using less energy means relying less on electricity or gas which will show up as savings on energy bills.
• Noise reduction: Double glazing reduces noise by up to 40dB which means the noise outside is greatly reduced to a point where it is barely audible. With a 40dB noise reduction, a busy street outside can sound like a quiet library.
• Security: The two layers of glass make double glazed windows tougher to break and harder for burglars to break into, which improves security.
• Reduced condensation: The double panes of glass and argon filled gap give double glazed windows an extra thermal barrier which reduces heat transfer from inside to outside and vice versa. Without heat hitting cooler air, condensation cannot occur.
• Increased property value: The addition of double glazed windows to a property can increase resale value as potential buyers will pay more for homes with energy efficient features.
• Durability and longevity: Double glazed windows are more durable and last longer than other windows. Because of their construction they are resistant to damage, and the lack of condensation protects the frame from moisture.
• Enhanced aesthetics: With a large variety of window types and styles, double glazed windows can enhance the aesthetic appeal of a home.

Disadvantages of Double Glazing

• Higher upfront cost: Double glazed windows cost more to buy and install than other types of windows. However, the long term savings on energy bills make up for the higher price tag in time.

Advantages of Single Glazing

• Cost effective: Single glazing is a cheap way to get windows for a home.

Disadvantages of Single Glazing

• Less energy efficient: Single glazing is not energy efficient. Because it is a single pane of glass, it has a high U value which means poor insulation and low energy efficiency. The single pane of glass allows a large amount of heat to transfer from inside to outside which means significant heat loss in winter and heat gain in summer.
• Less insulation: Single glazing has very little insulation as the only barrier between the outside and interior is a small pane of glass.
• Higher energy bills: Energy bills will be increased with single glazed windows. The higher heat transference due to lack of insulation and thermal efficiency means heaters and coolers will need to work harder so energy bills will increase.
• Less noise reduction: Single glazed windows offer minimal noise reduction with the most being about 25% reduction of outside noise. This means up to 75% of the noise outside can still be heard inside the home. The sound waves cause the glass to vibrate which transfers the sound energy to the interior of the home.
• More condensation: Single glazed windows have more condensation because of the lack of insulation. The temperature difference between the interior and exterior is so vast that it causes droplets to form on the glass.

Understanding the Differences Between Double and Single Glazing

Whether you decide to install single or double glazed windows is entirely up to personal choice, However understanding the differences between the two can help you decide.

• Energy Efficiency in Double Glazing vs Single Glazing: Double glazing is significantly more energy efficient than single glazing, reducing heat transfer by up to 30% compared to single glazed windows. This reduced heat transference means less reliance on heating and cooling, lower energy consumption and higher energy efficiency.
• Costs of Double Glazing vs Single Glazing: Double glazing generally costs about 25% to 50% more than single glazing in upfront costs. However double glazing can save you up to 30% on energy bills which means significant savings moving forward.
• Impact of Double Glazing vs Single Glazing on Resale Value: Homes with double glazing tend to sell for a higher price than those without. The addition of double glazing increases home value by up to 10% because of their energy efficiency and reduced bills.
• Noise Reduction in Double Glazing vs Single Glazing: Double glazed windows have two panes of glass with an argon filled layer between them which reduces noise outside significantly. Single glazed windows, on the other hand, have one single pane of glass so outside noise is still clear. A busy road sounds like a library with double glazing, but with single glazing almost every sound outside can still be heard.
• Durability in Double Glazing vs Single Glazing: Double glazing is more durable than single glazing. While single glazing is more prone to shattering and condensation, double glazing is strong with increased resistance to outside elements like wind and rain.

Should I Install Double or Single Glazed Windows?

The choice to install double or single glazing will impact the energy efficiency of your home and therefore savings on electricity bills. While single glazing is traditional, double glazed windows are gaining popularity for their superior ability to keep homes warm, quiet, and secure. Double glazing can have a higher initial price than single glazing however the return on investment is significant. When deciding whether to install double or single glazing, it is important to consider the upfront cost is an investment that will pay off in the long run with substantial savings in energy bills.

Double glazing is far superior to single glazing due to its insulation and noise reduction properties. For many years single glazing was the most common form of glazing for new home builds and renovations. However, since the 1980s it has been rising in popularity with the focus on energy efficiency, sustainable living and savings on electricity bills. If you want to find out more about double glazing compared to single glazing, contact the experts at Windows for Life.