Setting up a rooftop solar system generally only takes a couple of days.
But don't let the short build-time fool you into thinking it's not a serious business. Besides being costly, mistakes can have disastrous consequences further down the road—like severe structural damage or, God forbid, a fire.
That’s what makes the solar inspection process is so important.
In this post, we’ll go through the kind of inspections you can expect to encounter when you make the switch to clean and renewable solar energy.
Initial inspection
Before any work begins, we’ll need to inspect your home to make sure there are no problems that would make installing a solar system unsafe.
There are two main areas of concern here.
Can your roof support the extra weight?
Can your electrical system safely handle the extra power?
Your roof
Solar panels and the necessary mounting equipment typically weigh in at around three pounds per square foot. That puts the full weight of an average-sized 300-square-foot solar system at almost 1000 pounds.
Now, if your roof is in good condition, handling that much extra weight won't be an issue—building codes generally require roofs to be capable of handling at least 20 pounds per square foot.
The problem is, of course, that not everyone's roof is in good condition.
So, before we can start installing your solar system, we’ll need to make sure that your roof isn’t damaged in any way that would make adding the extra weight of a solar system hazardous.
Your electrical system
Similarly, if your electrical system is up to code and functioning properly, integrating solar panels into it shouldn’t be an issue.
But electrical problems—even very serious ones—can sometimes go unnoticed.
And, even if the electrical system is functioning just fine, in older houses the wiring sometimes isn't up to current code. Service boxes in older homes also sometimes limit the amount of power that can be sent back into the grid.
Finally—though this is thankfully pretty rare—even if your home is new it’s possible the original builder failed in his duty to make sure your electrical system is up to code.
So, in addition to your roof, before we start installation we’ll also need to inspect your electrical system to ensure there are no issues that would make adding a solar energy system hazardous.
Municipal inspection
Once we’ve installed your solar system, your municipality will obviously want to inspect it to make sure it’s up to their building and electrical codes.
The precise electrical codes that are in force will vary depending on your local building department. But they’re pretty much always based on a set of standards developed by the National Fire Protection Association.
Typically, your local inspector will make sure that:
Your service panel meets local electrical codes
All wiring and connections are properly made
Your system’s configuration matches the original electrical diagram to ensure that all essential components have been included
Your system is properly grounded in accordance with all manufacturer’s installation guides
There are no problems with your roof that would stop it from being able to support the extra weight
Your panels and racking are properly secured
Your conduit runs, connectors, wiring, and inverters have all been installed correctly
All necessary site placards and warnings have been posted on your equipment
Permission to operate
Once it’s up and running, your solar system won’t just be generating power to run your home.
Since you’ll be selling any surplus energy it produces back to your utility company, it also has to be capable of exporting electricity back into the grid.
As such, an improperly installed system can be hazardous not just to your home, but to your entire local distribution grid.
So, before you can connect to the grid and start operation, your local utility company will require proof that your municipality has inspected and approved your system.
Some utility companies may also send out their own inspector to make sure all the electrical work is up to snuff.
Once your utility company is satisfied that there are no safety concerns, you’ll receive Permission to Operate (PTO), which signals the end of the installation and inspection process.
At that point, your solar system can go online without you, your neighbors, or any other concerned parties having to worry about whether it's safe.