The Importance of a Solar Site Survey
Last Updated January 6, 2024
By Michael Jones
Michael literally wrote the book on solar (it’s called The Homeowners’ Guide to Going Solar) and has been a solar consultant for over four years.
Understanding the intricacies of a solar site survey is crucial for homeowners considering going solar. A comprehensive solar site survey is the foundation upon which successful installations are built, enabling the solar company to design a system tailored specifically to your home’s unique characteristics.
In this post, we’ll delve into why in-person solar site surveys matter and explore key elements examined during a survey. We’ll also guide you through post-site survey steps including finalizing design and dealing with necessary home upgrades before installation.
By understanding your house’s unique project requirements through a detailed solar site survey, you your your solar company can make an informed decision about going solar.
Why You Need a Solar Site Survey
The solar site survey isn’t just about determining whether your house is exposed to enough sunlight; it’s also about recognizing potential problems that could affect the setup and effectiveness of your solar energy system. Or even whether solar is feasible option for your home at all.
Why an In-Person Solar Site Survey Matters
Some solar installers, in the name of efficiency, opt for a fairly rudimentary remote survey using satellite imagery and a handful of photos, perhaps taken by the sales rep. We’re not big fans of this approach.
An in-person solar site survey gives you more than just a general idea; it provides detailed insights into whether going solar would be feasible for you. A professional technician will visit your property to evaluate factors like roof condition, shading, and electrical infrastructure that can significantly affect how well a solar panel installation is likely to perform.
Timing of the Solar Site Survey
The solar site survey is typically scheduled for about a week after the customer has expressed a firm interest in at least exploring solar, usually by signing off on a preliminary agreement.
It may be tempting to assume that both parties are fully committed when an agreement is made but it isn’t until the site survey is completed that the home’s full solar potential can be seen
So why even bother with a preliminary agreement prior to site survey, you may ask.
That’s because carrying out a site survey requires significant cost on the part of the solar installer. It is likely that this is the first time they will be spending money to assess the solar suitability of your home. Therefore, they want to make sure that you are a serious customer before investing in the survey.
Key Elements of a Solar Site Survey
The solar site survey is where the solar installer determines if your home is a good candidate for solar. Sunrun has arguably the most thorough site survey in the industry, covering a 91-point checklist. There are five main areas the site technician is going to look at.
Confirming How Much Sun You Get
The satellite image provided by the sales rep is a decent starting point for a conversation about solar but it doesn’t give the full picture. We’ve had many experiences consulting for solar projects with customers only to find out that the satellite image used was out-of-date.
It can be embarrassing when a customer looks at a satellite image of their home and immediately recognizes the car in the driveway that they sold two years ago.
So your solar company will likely want to take a closer look in order to make the most accurate readings. They might use a measuring tool such as Solmetric’s SunEye-210, which is one of the most advanced shade measurement devices available. It’s essential to use a tool like this to accurately assess how much sun your roof gets.
Identifying Shaded Areas and Roof Obstructions
For most homes on Cape Cod, trees are usually the biggest obstruction to a home’s solar potential. They grow over time, of course, and therefore cast an ever-changing shadow. Deciduous trees shed their leaves in winter, which means the shadows they cast at that time of year are very different from the ones they cast in summertime.
A solar site survey will help to determine which trees are likely to create shade issues on the roof and how the trimming or the removal of certain trees may affect sun hours.
We’ve been able to make deals more appealing for customers by pointing out that if a certain tree is trimmed or removed, it could lead to increased sun hours and higher savings over time.
Checking Roof Pitch and Condition
The angle of the roof (or pitch) is also difficult to assess from a satellite, and it’s critical since it plays a huge role in determining the angle at which the solar panels will be installed as well as the safety of the crew carrying out the installation.
A steep pitch will be more challenging for solar installers and may take longer to complete. Conversely, roofs with very low pitches (less than 10 degrees) may require the use of rubberized material to prevent leaks and should only be installed in warm weather conditions.
Regardless of the pitch, the condition of the roof itself is a crucial consideration when considering a home’s solar potential, particularly on Cape Cod, where the housing stock tends to skew older. More than half of the solar projects we install require us first to have a serious discussion with the homeowner about the condition of the roof.
A comprehensive solar site survey will evaluate both the condition of the shingles on the exterior and assess the structural integrity of the roof to ensure it can support additional weight from solar panels.
Assessing Roof Obstructions
Obstructions on the roof, such as vents, TV satellite dishes and other items, can also present problems. And they can sometimes be difficult to pick up from satellite images. A site survey will determine whether these obstacles can be moved or removed to give the design team more flexibility in where they can place panels.
Inspecting Main Service Panel
Evaluating the main electrical service panel is arguably the most important aspect of a solar site survey, since that’s what will determine how the solar panels will be connected to the home’s electrical system.
And it goes without saying that it’s best to have a trained specialist inspect your electrical panel.
That expert will be able to determine the amp service, the busbar rating, the number and types of circuits that are available, as well as what sort of equipment or service upgrades may be needed.
After the Site Survey
Once the solar site survey is completed, the solar company will use all the information gathered to nail down your system’s final design. This might be essentially unchanged from the original one you were show or it might be quite different. Either way, the rep will come back and explain what it all means and what effect it’s going to have on your solar project.
When it comes to home upgrades, who will take care of them and who will cover the costs? And how does the new information affect the price, the type of deal or even the feasibility of the entire project?
It is a common misconception that going solar is pretty much the same for every house, when in reality each home has its own individual quirks and is its own unique project.
That’s why it’s crucial to conduct a full site survey to determine if a property is suitable for solar installation before any final decisions can be made by either the customer, the solar company, the town or the utility.
If you would like to see if your house is a good candidate for solar, the Cape Cod Solar Guys can walk you through the process. We’ll offer you expert guidance with no pressure. You can contact us to set up a time to chat.
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