Why You Need a Solar Study Before You Build

The sun can make or break a design. So what if we told you that at the very early stages of designing a home, especially a custom mountain home, there was a tool that would allow you to look at a projection of exactly where the sun was going to be, inside and outside of your house, every single day of the year? This information would be invaluable to help you make good choices about design as you move forward. Luckily, there is such a tool and it is called a solar (or sun) study.

What is a solar study?

The orientation of this home allows it to be almost entirely naturally lit, with the sun coming in from every side.

A solar study is a relatively simple tool that many clients are unfamiliar with. Many architects are already using 3d modeling to help clients envision the home they are building, and most of these programs can produce sophisticated solar studies. Your architect can simply plug in the coordinates of your building site and a model of the home you are building, and the software will create still shots or videos that show shadows within the interior of a home as well as the surrounding area as the sun passes through a day, a season, even a year.

Why is a solar study important?

Strategic placement of doors and windows allows for a balance of light to stream in from both sides of this cozy great room.

Global warming has made a huge impact on the American West. In the past, our clients were mostly worried about seeking more sun in our cooler climate. This is no longer the case as the intensity of the sun is getting stronger. Now, the goal is still to take advantage of the warmth of the sun, but in a more controlled way. Even in winter, when the sun is low and intense, it can overheat a house very quickly. We also want to control glare from the sun as it can obscure views, especially for homes looking west along the front range. 

A solar study can also help inform important design decisions maximizing energy efficiency both on the exterior and interior of the home, from how to position the home on the site and where to incorporate windows and window coverings to the size of roof overhangs and placement of shade structures and landscaping, to name just a few. In addition, a sun study can also help plan for snow mitigation and management, such as preventing ice buildup on decks and driveways.

The strategic placement of windows allows graceful natural light to stream into this primary bathroom.

Over the years, we have compiled many examples of solar studies that have been invaluable for both our client and for us. Here are two:

Evergreen Sun Study

From left to right: projections of sun exposure at 4:00 in the evening on the winter solstice, spring equinox, and summer solstice.

One of the goals for this project in Evergreen was to maximize the sun exposure on the deck on the southwestern corner of the home. As you can see in the images above, the sun provides deep penetration across the deck and into the home in winter, providing warmth to the home in the colder months. In spring the deck is mostly sunny, allowing the homeowner to bask in the cool spring sunshine. And in summer, the study showed good shade coverage because of the large cover over the deck.

Breckenridge Sun Study

Sun study of home in Breckenridge at the winter solstice (left) and summer solstice (right).

The solar study for this home in Breckenridge illustrates how the positioning of the home allows the warmth of the sun in the cold winter months and blocks the sun’s intense rays in the summer. During the winter solstice, the low sun penetrates so far into the house that it goes all the way through the home. You can even see sunspots from the windows on the other side of the house as it slices through the house early in the morning. At the summer solstice, the house and interior courtyard are completely shaded on the interior based on the overhang of the house and the direction of the house’s placement.

Aaron Ruiz is a project manager at TKP Architects, an award-winning architecture firm based in Golden, Colorado. View TKP’s profile or contact TKP Architects at 303.278.8840.

Content for this article provided by TKP Architects.