What Is a Good U-factor for a Window—and Why Does It Matter for California Homes?

what is a good u factor for a windowIt’s nothing drastic, but I’ve put myself on a little diet. I’m not cutting out any major food groups or anything like that, but I am paying much closer attention to the nutritional labels on foods I eat, as well as to the calorie counts they give you at restaurants. I find that having this extra knowledge helps me make smarter choices with what I eat. And you know what? I’m already noticing a difference. I’ve already lost a few pounds and am feeling great.

I think this lesson is also helpful when it comes to picking out new windows for your home. I talk about this quite a bit, but windows really do more for you and your house than just look pretty—they are a key factor in making sure your house is energy efficient. And while windows certainly don’t come with calorie counts like food does, they do have something called a U-factor. This is why, today, I want to talk about what a U-factor is, what is a good-U factor for a window in California, and why it matters.

Window U-factors Explained

I want to start by explaining what a U-factor is because I know the term tends to fly right over most homeowner’s heads. They may see it on window performance stickers, but often overlook its significance because they don’t understand what it is.

Essentially, the U-factor is the measurement of a window’s energy efficiency.

Essentially, the U-factor is the measurement of a window’s energy efficiency. More specifically, this measurement is used to indicate the amount of heat transfer a particular window allows. In even simpler terms, the U-factor lets you know what a window’s insulating power is.

Generally speaking, U-factors range between .25 to 1.25, but can be even lower for windows designed for colder climates, down to about .17. What can get a little confusing about U-factors is that the lower the U-factor, the better the insulating power. That’s why I like to think of U-factors in terms of heat transfer—the lower the number, the less heat that will transfer across the pane, and the more energy efficient the window is. In the summer, less heat will make its way into your home; in the winter, less heat will leak out.

What Is a Good U-factor for a Window in California?

So, now that you know what a U-factor is, how do you know what is a good U-factor for a window on your home? As a general rule here in California, I usually recommend that people look for windows with a U-factor less than .30.

As a general rule here in California, I usually recommend that people look for windows with a U-factor less than .30.

If your energy bill tends to be on the higher side, you use a lot of air conditioning, or you are just really concerned about the energy efficiency of your home, perhaps choosing windows with a U-factor of .25 is a better bet. They will give you superior energy performance and help keep your home nice and cool in the summer, and nice and warm during the chilly winter months. You’ll also probably notice savings on your energy bill during peak heating and cooling seasons because your HVAC system won’t have to work as hard to keep the temperature regulated in your home.

You’ll also probably notice savings on your energy bill during peak heating and cooling seasons because your HVAC system won’t have to work as hard to keep the temperature regulated in your home.

Another bonus of investing in windows with a good U-factor here in California is that they may qualify for rebates or financing. There are many amazing energy efficiency incentive and financing programs available to California homeowners making energy efficient upgrades to their homes, like installing new windows with low U-factors, so be sure to take advantage of these great deals.

How to Choose and Install the Best Windows for Your California Home

My hope is that by this point you feel like you have a good understanding of U-factors and what to look for when choosing new windows for your California home. If I’m being totally honest, though, there are a lot of other important factors to consider when choosing windows, like the solar heat gain coefficient, visual transmittance, and condensation resistance.

I wish choosing the best windows for your home was simple, but it can be a bit complex. That’s why I strongly recommend that you work with a contractor and window expert like the friendly folks at Bell Brothers. They’ll be able to come to your home and do a free energy assessment that will help them determine which windows would be best for your California home.

Believe it or not, no matter how low a U-factor your windows have, if the installation isn’t done properly, they won’t make a big difference.

They’ll also be able to install your new windows for you to ensure that you’re getting the biggest benefit in terms of energy efficiency. Believe it or not, no matter how low a U-factor your windows have, if the installation isn’t done properly, they won’t make a big difference. And while it may sound too good to be true, the folks at Bell Brothers are also well versed in California energy efficiency financing programs so they can help you get the financing you need to get the project done.

Like I said before, having the right knowledge makes all the difference, whether it’s about nutrition or windows. And just like I’m seeing with my diet, I can assure you that having windows with a good U-factor will give you great results.

At Bell Brothers, our trained window professionals would be delighted to help you choose and install energy efficient windows to improve your home’s energy efficiency. Contact us today to schedule a free consultation.

Wondering how to finance new windows—or even a furnace or plumbing upgrade? HERO is a unique financing option that helps California homeowners afford energy efficient upgrades to their home. Contact Bell Brothers, a HERO-approved contractor, to learn more. Our local window, HVAC, and plumbing specialists will walk you through the entire process, from applications to installation.

Image courtesy Unsplash user Petter Rudwall