Energy Efficient Windows San Diego – Reduce Your Energy Bill

Energy Efficient Windows San Diego – Reduce Your Energy Bill

January 30, 2020
Martin Whitmore, President of US Window & Door

Keep cool in San Diego with energy-efficient windows. Each component of the window is carefully designed to help regulate temperature and maximize efficiency.

Choose only the best for your home

When you’re building or remodeling your own home, you want the best. After all, you don’t want just any brick, just any kind of wood, and you likely won’t pick the cheapest shingles on the market. This is your home and it’s essential to choose only the best.Not only are there vastly different kinds of glass, but different coatings, applications, subtle tinting differences, and all manner of other considerations that affect your window performance. The wrong windows can cost you up to $465/year extra, so it pays to keep some things in mind when you’re deciding what brings light into your life.

What to consider when choosing energy-efficient windows for your home

There are several considerations to keep in mind when making any decisions for the construction or remodel of your home; certainly, this includes your choice in windows. The number of glass panes in your windows, the coating on each pane of glass, the window frame and several other factors all play an important role in keeping your energy bills low year-round. This article will thoroughly explain what should be considered in choosing only the best for your home.

How many panes of glass should your windows have?

The first thing to consider is how many panes of glass your windows have. Most older windows consist of a single pane of plain glass in a fully wooden frame. While it certainly keeps the wind out, it’s not the most energy-efficient option. Your standard single-pane window can drive up your heating and cooling bill with all the thermal energy passing through it. Double- or triple-glazing your windows will help regulate the temperature in your home far more effectively than a standard single-glazed window. Double-glazed windows have two panes of glass and triple-glazed windows have three. Between these panes of glass is a certain amount of harmless, odorless gas (in this case, argon or krypton) which is used to enhance thermal performance by helping to insulate the interior of your home. The gas between the panes serves to slow down temperature changes caused by warmer or cooler weather outside the house, and simultaneously slows down the escape of heat and cold from inside the house.


What are some differences between these two gases?

Regarding these two gases, krypton is the better choice of the two, but argon is less expensive. Both of these gases are odorless and harmless, and each does an excellent job of insulating. The principal difference between the two gases is their respective densities. Argon is six times as dense as air, and krypton is six times as dense as argon. What this means is that argon takes longer to react to changes in temperature than air, and krypton takes longer than argon. It also means that you can fit more krypton into a smaller space than argon. As a result, krypton is the better choice for triple-glazed windows, since the space between panes is smaller (¼”-⅜”) than in a double-glazed window (½”).

Differences in spacer materials

A spacer is sealed between panes to keep the gas intact. These spacers are the next important component of the ideal window. As you might expect, different spacer materials have different effects on window performance. Older multi-pane windows employ an aluminum spacer lined with a desiccant (which is a substance used for absorbing moisture). This both seals out moisture and absorbs any moisture that gets through. We have taken the same application and come up with two far more effective material options than the already effective choice of aluminum, namely tin and stainless steel. The purpose of the spacer is to help in slowing down changes in temperature as much as possible, so the better the insulating properties of the material, the less effective it is as an energy-efficient spacer. Stainless steel is a poor conductor of heat and cold, which makes it more effective than tin. However, tin is less expensive and it also insulates well.

Energy-efficient window coating options – Low-E (low-emissivity)

We touched briefly on the idea that plain, single-pane windows let a lot of heat in or out; now to move on to the next point: UV radiation. Plain glass lets in a lot of UV rays which can damage your carpet and furniture and bleach your hardwood floors. To combat this, it’s best to have a low-emissivity coating for your windows. Low-E is a solar control coating that improves the thermal performance of your windows by reflecting long-wave heat energy and absorbing short-wave heat energy. This means that infrared rays from the sun, which increase the heat of the objects they strike, are absorbed by the Low-E window coating; while the ultraviolet rays that can cause damage to your furniture, floor coverings, and hardwood floors, are reflected back outside.

4th Surface coatings work with SHGC (solar heat gain coefficient)

As much as has been said in favor of triple-glazed windows, it should also be noted the benefits of different window coatings, namely 4th Surface. 4th Surface is a Transparent Conductive Oxide coating, which essentially has the same effect as the third pane of glass, better-reflecting heat back into your home. (There are so many things to customize about these windows, it’s ridiculous.) 4th Surface is a specific Low-E coating with an excellent U-factor ranging from .20 to .30, measured at the center of the glass. (Note here that the center of the glass does not tend to have the same ratings as the entire window.) Of course, at this point, we need to explain what a U-factor is. Isn’t it fun to learn? The U-factor is a measure of heat loss, basically how well the window (or the skylight, or the patio door, whatever energy-efficient glass surface you like) can withstand heat transfer.

Solar Heat Gain Coefficient, or SHGC, is a quantifiable measure of solar heat transfer. SHGC is expressed from 0 to 1. So a window treated with a Medium-solar-gain 4th Surface coating would have a center glass U-factor rating of .20 and an SHGC rating of .41. What this means is that only 41% of solar heat is transmitted through the said treated window. That same window also transmits 70% of visible light. A window treated with a High-solar-gain would read, at the center glass, a U-factor of .21 and an SHGC rating of .62, meaning it transfers 62% of solar heat. If you want to know, that one transmits 77% visible light. Lastly, the Low-solar-gain treatment will present a center glass reading with a U-factor rating of .20 and an SHGC rating of .27 (transmitting 27% of solar heat), transmitting 63% of visible light.

Choosing the best material for your energy-efficient window frames

An effectively energy-efficient window paired with just any typical window frame can make your window far less energy-efficient. As such, it’s important to make the most informed decision possible. Among your options are vinyl, fiberglass, and aluminum.

window buying guide


Vinyl or PVC (Polyvinyl chloride) is generally accepted to be the best option for an energy-efficient window frame, given its low-maintenance nature and general cost-effectiveness. It doesn’t take much to clean these window frames, and they maintain their shape well over the years. There is no need to worry about the swelling, rotting, or warping that’s common to a typical wood frame.


Fiberglass is an excellent option as well  as it is made of similar raw materials to the window itself. Fiberglass is made from small glass fibers and resin; as a result, fiberglass will process temperature changes at more or less the same rate as the glass panes in the window. Fiberglass is also a low-maintenance option, easy to clean and maintain its shape without the common downsides of wood, and is also inexpensive like vinyl.


Aluminum is reliable and sturdy and provides a decent frame for your window. It is also inexpensive, but it has its downsides if you live in a coastal area with a lot of salt air, like San Diego. It isn’t advisable to use this material in these regions, being so prone to corrosion in that setting. Also, as discussed in the section about spacers, aluminum is an excellent conductor of heat and cold, making it a less effective insulating material. However, aluminum is an excellent choice for a more temperate climate, and regardless of the situation, we will still happily work with this material if it is the one you choose.

Noise-reduction options for energy-efficient windows

In addition to all these wonderful light and heat-related benefits of energy-efficient windows, there is also the option of noise reduction. STC (Sound Transmission Class) windows help to keep your home quiet and give you even more peace of mind than just saving money on your energy bills. STC, measured in decibels, quantifies the effectiveness of a window in reducing sound. The higher the rating, the better. To reduce noise transmission through windows, mass is added, making the panels thicker. The space between the panes of glass allows the sound waves to dissipate further before what’s left of them makes it into the house. In STC windows, the spaces between panels may be a bit larger than in standard energy-efficient windows, to allow better soundproofing.

Safety glass

Safety glass is highly advised; It can still break, but it shatters into pebble-sized pieces, instead of shards which are sharper, and more prone to causing injury. They also break inconsistently, and there will be large, easy to gather pieces with little, invisible glass splinters mixed in that can make post-clean-up injuries more likely. When the glass breaks into pebble-sized pieces, the pieces are far more consistent in size, making cleaning up effectively a much simpler process. Pebble sized pieces are also less prone to cutting you, being a little more round than a glass shard. Safety glass is tempered, meaning that it is heated and then very rapidly cooled down. Tempered glass does not break as easily as normal, or annealed, glass. Heating the glass and then cooling it down rapidly puts the glass simultaneously into tension and compression. Glass is sometimes strengthened through a chemical process. This is usually the process used for a glass of a more complex shape. This is done using an immersion bath of potassium nitrate. While it is generally tougher than the thermal process, the latter is still notably durable. All that to say, go for it. You literally can not go wrong being as safe as you can be.

Obscure options

With any energy-efficient window, there are several “obscure” options, which are ideal for bathroom windows or any other room where you’d rather not be seen. “Obscure” in this context has to do with a blurring effect in the window, intentionally obscuring the view of the onlooker. This makes for an ideal privacy window and can add a beautiful aesthetic.

Milgard proudly partners with Energy Star

As a proud partner, Milgard has all of its windows and patio doors Energy Star rated. Energy Star is a program that works in conjunction with the Environmental Protection Agency and the U.S. Department of Energy to help reduce energy costs for Americans and to help protect the environment through the use of energy-efficient products. In 2007, more than $16,000,000,000 was saved on energy bills across America thanks to the efforts of Energy Star. All Energy Star qualified products are independently tested and certified by the National Fenestral Rating Council (fun word).. If you’re curious, we encourage you to visit their website at

Hopefully, this has helped you in your decision-making process. Choose only the best energy-efficient windows for your San Diego home and enjoy saving money on your energy bills year-round. We look forward to helping you with all of your energy-efficient needs.