Last Updated on September 24, 2023
What is Low-E glass windows? Low-E glass windows, also known as low-emissivity glass, are designed with a unique coating that reflects heat and blocks up to 99% of UV rays. This design minimizes heat transfer, protects interior furnishings from UV damage, and promotes energy efficiency in buildings.
Low-E Glass windows are a highly effective solution for those who want to reduce the amount of heat and UV light entering their building. This type of glass has a special coating that reflects heat back into the home and utilizes metallic particles like silver or titanium to reflect infrared radiation.
Not only do Low-E Glass windows reduce heat, these windows also block up to 99% of UV rays entering the building, which protects furniture and interior items. As well as this, double-paned windows have an insulating layer between the two panes, which further reduces the transfer of heat.
If you want to know more about how Low-E Glass windows can benefit your building, keep reading to explore all the important details.
Definition of Low-E Glass
Low-E glass, or low-emissivity glass, has a special coating designed to reduce the amount of heat that passes through it. This coating works by reflecting heat back to its source, keeping it inside during colder months and outside during warmer months.
The term “emissivity” refers to how well a material radiates energy. In the case of windows, high emissivity means that they allow more heat to escape or enter your home. Low E glass has a lower emissivity than regular glass windows, which makes it more energy-efficient.
This type of glass is commonly used in residential and commercial buildings to help reduce energy consumption and costs associated with heating and cooling systems. Additionally, low-E glass can also provide UV protection and increased comfort indoors.
How Does Low-E Windows Work?
Low-E glass reduces energy consumption by reflecting heat back towards its source through a special coating applied during manufacturing.
Tin and silver oxides are applied in multiple layers in a vacuum-sealed chamber to create a coating that reflects infrared light.
Low-E glass reflects heat back outside in the summer and keeps the heat generated inside a building in the winter, reducing the need for air conditioning and heating.
Modern Low-E coatings minimize the effect on visible light transmission, allowing natural light to enter a room while still benefiting from reduced energy consumption.
Different Types of Low-E Coating
There are two main types of Low-E coatings (hard coat and soft coat) and two panes (single or double) options, with trade-offs between durability, energy efficiency, and cost.
Hard Coat Low-E Glass
Hard Coat Low-E Glass is an advanced type of window glass produced through a pyrolytic process. This involves applying a thin layer of molten metal to a sheet of glass during manufacturing, resulting in a durable window material that is less likely to scratch.
It is best suited for storm doors and windows due to its high durability and resistance to extreme weather conditions.
In terms of affordability, Hard Coat Low-E Glass typically costs more than soft Low E glass, but it offers additional benefits such as the ability to accessorize with in-between blinds.
Hard Coat Low-E Glass has a higher U-value due to the minimal number of layers present in the film, making it an energy efficient choice. The higher heat gain coefficient also allows more heat transfer into the living space while reducing energy costs.
Soft Coat Low-E Glass
Soft coat Low-E glass is a type of glass that has been treated with vacuum deposition technology to coat it with very thin and delicate material. This highly energy-efficient coating allows for high visible light transmission without obstructing views or obscuring the vision.
The coating also provides effective solar control, drastically reducing energy bills in comparison to other glass types. Furthermore, this type of glass also has less UV transmission, making it more resistant to sun damage.
However, soft coat Low E glass does have some drawbacks: it is more fragile and less durable than hard Low-E coating and therefore, not recommended for external applications.
Tempering this type of glass is more difficult, thus making the installation process complex and time-consuming, and the costs associated with this type of glass are higher due to its fragile material and complex installation process.
Single Pane vs Double Pane Low-E Glass
It’s important to think about whether you want single-pane or double-pane low-E glass. Single pane low-E glass has a coating applied to only one side of the glass, while double pane low-E glass has the coating applied to both sides of the inner layer of glass.
Single pane low-E glass is typically less expensive than double pane but offers less insulation and energy efficiency. This means that if you live in an area with extreme temperatures, you may notice a difference in your energy bills with single-pane low-E glass compared to double-pane.
On the other hand, double-pane low-E glass provides better insulation and energy efficiency due to the added layer of air or gas between the panes. This can result in greater cost savings over time and increased comfort indoors.
It’s important to note that while double-pane low-E glass may be more expensive upfront, it can provide a higher return on investment in terms of energy savings and overall comfort.
Additionally, some local and state governments offer rebates or incentives for installing energy-efficient windows, which can help offset the initial cost.
How Does Low E Glass Windows Affect Natural Light?
Metal oxide coatings on Low-emissivity (low E) glass help reduce infrared and ultraviolet light but still let visible light through. As a result, low E glass can affect natural light in several ways:
- Reduced Glare: Low-E glass can reduce glare from the sun by filtering out some of the light that causes glare. This can make indoor spaces more comfortable and reduce the need for shading devices.
- Improved Comfort: Low-E glass can improve indoor comfort by reducing the amount of heat that enters a building through windows. This can help maintain a more consistent indoor temperature and reduce the need for heating and cooling systems.
- Enhanced Natural Light: While low-E glass does reduce some of the sunlight that enters a building, it still allows a significant amount of visible light to pass through.
In fact, many low-E glass products are designed to enhance natural light by reducing the amount of reflected light and increasing the amount of transmitted light. This can help to create a more pleasant and natural-looking indoor environment.
Is Low E Glass Worth It?
Several factors must be considered when considering whether low-E glass is worth it.
Firstly, the initial cost of low-E glass can be higher than that of regular glass. However, the long-term benefits can outweigh this cost. One of the main advantages is energy efficiency.
Low-E glass has a special coating that reflects heat back into a building during cold weather and reflects it away during hot weather, reducing the need for heating and cooling systems. This can lead to significant cost savings on energy bills over time.
Another benefit of low E glass is UV protection. The coating on the glass helps to block harmful UV rays from entering a building, which can cause fading and damage to furniture and other items inside.
Additionally, low-E glass can provide increased comfort indoors by reducing drafts and maintaining a more consistent temperature.
Benefits of Low-E Glass
Low-E glass offers numerous benefits for homeowners who want to reduce their energy consumption and save money on utility bills while protecting their belongings from harmful UV radiation.
With its various types and considerations when deciding if it’s worth it, Low E glass is a popular choice for those seeking an eco-friendly and comfortable home.
Energy Efficiency
Low-E glass has a special coating designed to reduce the amount of heat that passes through it. This makes it an excellent option for homeowners looking to improve the energy efficiency of their homes.
The energy efficiency of Low-E glass is due to its ability to reflect heat back into the room instead of allowing it to escape through the window.
The coating on the glass is made up of microscopic layers of metallic oxides, which are applied using a vacuum deposition process. These layers work together to reflect infrared light and prevent heat from escaping.
Cost Savings
Low E Glass is a type of glass that is specially designed to reduce energy consumption and costs. It works by reflecting heat back into the room, reducing the energy needed to keep the room at a comfortable temperature. This can result in significant cost savings over time.
One of the main benefits of Low-E Glass is its ability to save money on energy bills. Reducing the amount of heat that escapes from a building, it can help to keep heating costs down during the colder months. This can be especially beneficial for homeowners who live in areas with harsh winters or high energy prices.
UV Protection
This glass is particularly important for areas with high levels of sun exposure, where UV rays can cause damage to furniture, floors, and even skin.
The Low-E coating on the glass helps to block out up to 99% of the sun’s harmful UV rays. This means that items in your home or office are protected from fading, discoloration or damage caused by prolonged exposure to sunlight.
Low-E glass can help protect occupants from skin damage caused by prolonged exposure to UV radiation.
UV protection is especially important for homes and buildings located in areas with high levels of sun exposure.
For example, if you live in a coastal area or an area with long summers, then you may be more susceptible to the harmful effects of UV radiation. Low E glass provides an effective solution for reducing these risks while still allowing natural light into your space.
Increased Comfort Indoors
Low-E glass helps reduce energy consumption and save costs and contributes to increased comfort indoors. This type of glass is designed to regulate the amount of heat that enters or exits a building.
By reducing the amount of heat transfer, Low-E glass helps maintain comfortable indoor temperatures regardless of the weather outside.
One way in which Low-E glass increases comfort indoors is by minimizing drafts. Since it reduces heat transfer, there are fewer cold spots near windows and doors, which can cause discomfort for occupants.
Additionally, Low-E glass reduces glare from the sun without compromising natural light levels. This means that you can enjoy bright and natural light indoors without worrying about harsh glares that can cause eye strain.
Another way in which Low E glass contributes to increased comfort indoors is by reducing noise pollution. The thicker Low-E glass panes help dampen sound waves from outside, making your home or office quieter and more peaceful.
What to Look for When Choosing Low-E Glass?
- U-value: This measures the rate at which heat flows through the glass. A lower U-value indicates better insulation properties, which is important for energy efficiency.
- Solar Heat Gain Coefficient (SHGC): This measures the amount of solar heat that passes through the glass. A lower SHGC means less solar heat enters the building, which can help reduce cooling costs in warmer climates.
- Visible Light Transmission (VLT): This measures the amount of visible light that passes through the glass. A higher VLT means more natural light enters the building.
- Glare Reduction: Low E glass can help reduce glare and improve visual comfort. Some types of Low-E glass have a lower reflection rate, which can also reduce glare.
- Durability: Look for durable Low-E glass that can withstand harsh weather conditions, such as strong winds or hail.
- Aesthetics: Consider the appearance of the glass and how it will fit in with the overall design of the building.
- Cost: Finally, consider the cost of the Low-E glass and whether it fits within your budget. Keep in mind that higher-performing Low-E glass may have a higher upfront cost but can save money in the long run by reducing energy costs.
What is the Difference Between Low-E Glass and Regular Glass?
Low-E glass (or low emissivity glass) is a type of glass that has a special coating applied to the surface. This coating helps to block ultraviolet and infrared light from passing through the glass, which can help reduce heat gain in space.
Regular glass does not have this coating, so it allows more of the ultraviolet and infrared radiation to pass through. As a result, Low-E glass helps keep buildings cooler in hot climates, while regular glass does not provide as much insulation.
Low-E glass can also be tinted with different colors or even decorated with patterns, adding additional aesthetic appeal to a building’s design.
What are the disadvantages of Low-E glass?
The primary disadvantage of Low-E glass is the additional cost associated with it. Low-E glass can be up to 40% more expensive than standard glass and this cost can add up quickly if you are considering replacing all the windows in your home.
Additionally, Low-E glass does not guarantee the complete elimination of UV rays and heat, so it may not provide the insulation or protection from UV radiation that homeowners desire.
Lastly, depending on the type of glazing used to cover the Low E glass itself, condensation can sometimes occur on interior surfaces due to the low emissivity coating reducing the ability of air inside to escape through the window surface.
Enjoy Comfortable and Energy Efficient Living with Low-E Glass
Choosing whether or not to go with Low E Glass depends on many factors, such as climate, location, and energy costs.
Low-E Glass may be more expensive upfront but can often result in significant cost savings over time due to reduced energy consumption. This makes it a very attractive option for many people looking to build more energy efficiency while maintaining comfort levels.
Investing in Low-E Glass windows is worth considering when reducing energy costs while protecting your home from damaging UV rays.