Installation is only part of the timeline
Many homeowners are surprised that the physical installation of a rooftop solar system may take only a day or two, while the full project can take weeks or months from signed contract to switching the system on. Much of that time is paperwork: building and electrical permits, inspections, homeowners association review where applicable, and approval from the electric utility to connect to the grid. Understanding these steps helps you plan, ask better questions and spot delays early.
Requirements differ by city, county, state and utility, so treat this as a general overview and check the rules where you live.
Step 1: Local permits
Most local governments require permits for rooftop solar because the work involves the building structure and the home's electrical system. Depending on where you live, this may include a building permit, an electrical permit, or both. Applications typically include a site plan, an electrical diagram, equipment specifications and sometimes a structural review of the roof.
In most cases the installer prepares and submits the permit application. Ask each installer:
- Who applies for permits, and are permit fees included in the quote?
- How long does permitting usually take in my area?
- Will you need a structural engineer's letter for my roof?
Step 2: Homeowners association review
If your home is part of a homeowners association, read the governing documents before signing a solar contract. Some associations require you to submit plans for approval, and some have rules on where panels can be placed or how visible equipment can be. Many states have laws that limit how far an association can restrict solar, but the details vary widely. Allow time for the association's review cycle, which may depend on how often its board or architectural committee meets.
Step 3: Utility interconnection application
If the system will connect to the grid, the utility has to approve it. The interconnection application tells the utility what equipment you are installing and how it will connect. For most small residential systems the process is standardised, but larger systems, or homes in areas where the local grid already has a lot of solar, can face extra review. Some utilities need to replace or reprogram your meter.
This step is also where your billing arrangement is set, whether that is net metering, net billing or another export tariff. Ask the installer which rate or tariff your system will be on and what that means for how exported electricity is credited on your bill.
Step 4: Installation
Once permits are issued, the crew installs the racking, panels, inverter equipment and wiring. If the project includes an electrical panel upgrade or a battery, those may require additional permits or inspections.
Step 5: Inspection
After installation, a local inspector usually checks that the work matches the approved plans and meets electrical and building codes. If the inspector asks for corrections, the installer fixes them and the inspection is repeated. The homeowner sometimes needs to be present or provide access to the attic, garage or electrical panel.
Step 6: Permission to operate
Even after a passed inspection, the system should normally stay off until the utility gives formal permission to operate. Switching on early can violate the interconnection agreement. Once permission arrives, the installer typically shows you how to start the system and how to check its monitoring app.
Common causes of delay
- Incomplete permit applications or missing structural information.
- Backlogs at the local building department or utility.
- HOA review cycles that only happen at set intervals.
- Required electrical panel upgrades discovered late.
- Failed inspections that need a return visit.
Protecting yourself
Read your contract to see who is responsible for each step and what happens if approvals are delayed or denied. Ask whether you pay anything before permits are approved, and whether payments are tied to milestones such as installation or permission to operate. Keep copies of the approved permit, the final inspection record and the utility's approval letter. These documents are useful for insurance, warranty claims and, if you sell the home, for the buyer's due diligence.
Paperwork is rarely the exciting part of going solar, but a well-organised installer will handle most of it and keep you informed. For more questions to ask, read our guide to choosing a solar installer and the net metering explainer.