About 30% of a home’s heating energy is lost through the windows. One of the most effective projects you can do to improve your home’s energy efficiency is to replace them. Most windows have a life of 10 to 20 years, so if yours are older than that it’s time to upgrade. You can also use this opportunity to change the style or color of your windows to better fit your home’s decor.
When it comes to choosing a replacement window that will improve your home’s energy performance, there are several factors to consider.
1. Replacement options
When it comes to replacing windows in your home, you have two options: full frame or insert. A full frame window includes the windowpane and all the trim. It’s installed from the outside, similar to when it was originally installed during construction. Exterior trim and siding may need to be removed and replaced. However, this option provides the most variety of styles and colors and is the most efficient.
An insert is installed from the inside and fits into the existing window frame. The exterior trim and siding remain intact, lowering the cost of installation. Using an insert reduces the size of the windowpane by about 1 inch on all sides. Inserts can’t be used if the existing frame isn’t square or if its structurally unsound.
While many historical windows are comprised of only one layer of class, most of today’s models offer two or more layers that greatly improve their efficiency.
Double pane glass can be up to 37% better at preventing heat transfer, keeping your indoors warm in winter and cool in summer.
Triple pane glass reduces heat transfer by an additional 30%. It’s good for north facing walls.
Laminated glass, more commonly known as bulletproof glass, is composed of two sheets of tempered glass with an invisible layer of plastic between them. It can be used to prevent intruders, muffle sound, and protect your house from earthquakes and storm damage.
There are a variety of options for window frame materials, but the most common are wood, clad wood, vinyl, and fiberglass or composite.
Wood frames provide the most styles and options, but they can be vulnerable to water. However, many historic homes are required to use only wood framed windows.
To improve durability, wood frames are often clad in aluminum or vinyl. This improves the strength of their construction and adds aesthetic appeal.
Vinyl framed windows are a good value, require little maintenance, and come in a variety of styles.
Fiberglass or composite windows require little maintenance, are efficient, and are less prone to seal failures.
4. Other things to consider
If you are replacing your windows to improve the energy efficiency of your home, there are four things you need to look for when selecting a window: the Energy Star rating, U-factor, SHGC, and the VT. This information is found on the window label and comes from test data from the National Fenestration Rating Council.
Energy Star windows have been certified to reduce energy use by as much as 30%. The window label will show the areas in the United States that the window meets this criterion. Installing Energy Star windows, building materials, and appliances is a great way to improve your home’s energy efficiency.
A window’s U-factor measures how effectively a window stops heat flow. The rating goes from 0 to 1, and the smaller the number, the better the performance. The U-factor is the inverse of an R-factor, which measures insulation.
The solar heat gain coefficient or SHGC, measures the ability of the glass to block the sun’s heat. The lower the number, the less heat that gets in. In the Pacific Northwest, an SHGC of 0.32 or more can offset low U-factors up to 0.30.
The visible transmittance or VT specifies how much light passes through the windowpane. A VT of 0 is opaque, and 1 is transparent. Windowpanes with a VT of 0.6 or more appear clear. A VT below 0.4 creates a grayish cast.
Best brands for window replacement
Parr Lumber carries several replacement window brands, offering a variety of finishes, frames, hardware, and glass options.
Vinyl windows are a good value, improve energy efficiency, require little maintenance, and come in a variety of styles and colors. Parr Lumber carries the following vinyl window manufacturers:
- Ply Gem
Clad wood windows have an aesthetic appeal that complements many styles, provide lasting performance, and can add to your home’s value. Parr carries the following clad wood window manufacturers:
Fiberglass and composite windows are low maintenance, efficient, and provide a variety of glazing options. Parr carries the following fiberglass and composite window manufacturers:
- Integrity by Marvin
- Andersen 100 series