Energy efficient window replacement projects offer numerous benefits, including cost savings, improved comfort, environmental sustainability, increased property value, and access to incentives and rebates. These advantages make energy efficient windows a smart investment for homeowners looking to upgrade their homes while reducing energy consumption and enhancing overall quality of life.
What factors make a window energy efficient? Energy efficient windows are typically made of a combination of materials that optimize insulation, durability, and energy performance. Here are some common materials that make energy efficient windows:
1. Glass
Energy efficient windows often feature multiple panes of glass, separated by insulating gas. The space between these panes acts as a barrier, reducing the transfer of heat between the interior and exterior of the building. Many energy efficient windows are also coated with a thin layer of low-emissivity (Low-E) material. This coating is applied to the glass surface to reduce the amount of heat that can pass through the window while still allowing visible light to enter. Low-E coatings help reflect heat back into the building during the winter months and reflect it away during the summer, improving overall energy efficiency. In addition to thermal insulation, certain types of glass used in energy efficient windows can also provide sound insulation. This helps reduce the transmission of outside noise into the building, creating a quieter and more comfortable indoor environment.
2. Insulating Gas
Between the panes of glass in multiple pane windows, there is often a layer of insulating gas, such as argon or krypton. Insulating gas is denser than air, so it slows down the transfer of heat through the window. When the space between the glass panes is filled with insulating gas, it creates a barrier that reduces the flow of heat from the warmer side of the window to the cooler side and vice versa. Because insulating gas has a lower thermal conductivity than air, it provides better insulation. This means that windows filled with insulating gas are less prone to heat loss in cold weather and heat gain in hot weather compared to windows filled with regular air. As a result, buildings with energy efficient windows experience improved thermal comfort and lower energy bills.
3. Frame Materials
The frame material plays a significant role in the energy efficiency of the window. The thermal conductivity of the frame material affects how much heat can pass through the window. Energy efficient frame materials have low conductivity, meaning they are not as prone to conducting heat or cold into or out of the building. Common frame materials for energy-efficient windows include vinyl, fibreglass, wood, and composite, as they provide better insulation than others. Frames with thermal breaks feature insulating components that separate the interior and exterior parts of the frame, reducing the transfer of heat through the frame material. Energy efficient window frames are durable and properly sealed to prevent air leakage. High-quality frame materials resist warping, cracking, and deterioration over time, ensuring long-term energy performance and comfort.
4. Spacer Systems
Spacer systems are used to separate the panes in double-pane or triple-pane windows and maintain the integrity of the insulating gas fill. They are designed to minimize heat transfer around the edges of the glass panes, where the panes meet the window frame. Since the edges of the glass are more susceptible to heat loss, especially in cold climates, an effective spacer system helps create a thermal barrier that reduces heat loss and improves the thermal performance of the window. Furthermore, spacer systems help maintain a consistent temperature across the surface of the glass panes, reducing the likelihood of condensation formation on the interior surface of the window. High-quality spacer systems contribute to the longevity and durability of the window by reducing stress on the glass panes and seals. By minimizing heat transfer and thermal stress, spacer systems help prevent seal failure, glass breakage, and other issues that can compromise the energy efficiency and performance of the window over time.
5. Weather Stripping and Seals
Weather stripping and seals are installed around the perimeter of the window frame to create a tight seal between the frame and the sash, which is the movable part of the window. This seal prevents drafts and air infiltration, reducing the amount of conditioned air from escaping from the interior and outdoor air infiltrating into the building. In addition to reducing air leakage, weather stripping and seals also help improve the thermal performance of windows by minimizing heat transfer. By creating an airtight seal, they prevent warm air from escaping during the winter and hot air from entering during the summer. This insulation effect helps maintain a comfortable indoor temperature year-round and reduces the need for heating and cooling. Weather stripping and seals also prevent moisture infiltration around the window frame. By sealing gaps and cracks, they create a barrier that prevents moisture from entering the building envelope, preserving indoor air quality and protecting the structural integrity of the building. High-quality weather stripping and seals can lead to significant energy savings and improved building performance over time.
By combining these materials and design features, manufacturers create energy efficient windows that provide superior insulation, reduce heating and cooling costs, and improve indoor comfort. Consulting with a professional can help you select and install the right energy efficient for your home.