How to compare solar installers

Ask for their license number and verify it with your state's contractor licensing board — most publish a searchable database. Also confirm they carry general liability and workers' compensation insurance, and ask for a certificate of insurance rather than taking a verbal assurance. An installer who hesitates to provide either is a concern.

An in-house crew works directly for the company that sold you the system, so accountability is clear and quality standards are set internally. A subcontractor is a separate business hired to perform the install — which is not automatically bad, but it can complicate who is responsible when something goes wrong. Ask directly which model an installer uses, and how long they have worked with any subcontractors they rely on.

Workmanship warranties vary considerably between installers, so the useful comparison is relative rather than absolute — ask what each company offers and how it compares to the others you are considering. More important than the length is the fine print: what is actually covered, whether it is transferable if you sell the house, and whether it covers roof penetrations and labor or only the equipment.

This is a real risk in the solar industry, and it is worth asking about explicitly. Equipment warranties are usually held by the manufacturer rather than the installer, so they often survive; workmanship warranties typically do not. Ask whether the company has a track record of several years, and consider how much of your decision rests on a warranty that depends on them remaining in business.

Not automatically. Price is one axis, but a substantially lower bid may reflect lower-tier equipment, subcontracted labor, or a thin warranty. Equally, a much higher bid does not guarantee better work. The useful approach is to compare quotes on identical specifications first, then weigh price against warranty terms, crew model, and how clearly each company answered your questions.

Ask who performs the installation and whether they are employees or subcontractors. Ask for the exact panel and inverter models in writing. Ask what the workmanship warranty covers and for how long. Ask how many systems they have installed in your area. Ask what happens if the utility requires an interconnection upgrade. And ask for local references you can actually contact.

Ask for references from installations in your town or county, ideally completed at least a year ago so the homeowner has lived with the system through all seasons. Contact them and ask about the installation process, whether anything went wrong, and how the company handled it. How a company responds to a problem tells you more than a job that went smoothly.

Not by itself. Larger companies may have more resources and longer track records but also more layers between you and the people doing the work. Smaller companies may offer more direct accountability but less redundancy if something goes wrong. What matters is whether the company performs the work itself, honors its warranty terms, and can demonstrate relevant local experience.