Choosing the Right Solar Installer
Your solar installer is the most important decision in your solar journey. The same 8 kW system can cost $18,000 or $32,000 depending on who installs it, and the quality difference between a top-tier installer and a poor one can mean decades of trouble-free performance versus years of headaches.
Here are 15 questions every homeowner should ask before signing a solar contract.
Licensing and Credentials
1. Are you licensed and insured in my state?
Every state has different licensing requirements for solar installers. Ask for their contractor license number and verify it with your state's licensing board. They should carry general liability insurance and workers' compensation insurance.
2. Do you have NABCEP certification?
North American Board of Certified Energy Practitioners (NABCEP) certification is the gold standard in the solar industry. While not legally required, it demonstrates technical competency and commitment to quality. Prioritize NABCEP-certified installers.
3. How long have you been installing solar?
Experience matters. Companies with 5+ years of operation and hundreds of completed installations have proven track records. Be cautious with brand-new companies, especially those that recently pivoted from other industries.
Equipment and Design
4. What panel brands and models do you offer?
Top-tier panels include SunPower Maxeon, REC Alpha, Panasonic EverVolt, and Canadian Solar. Avoid installers who only offer one option or push the cheapest panels available. Panel efficiency, degradation rates, and warranty terms vary significantly between brands.
5. What inverter technology do you use?
There are three types: string inverters (cheapest, whole-array affected by shade), microinverters (per-panel optimization, best for partial shading), and power optimizers (middle ground). Ask why they recommend their choice for your specific roof.
6. How did you design my system size?
A reputable installer will design your system based on your actual electricity consumption (12 months of utility bills), roof orientation, shading analysis (using tools like Aurora or Helioscope), and local production factors. Be wary of installers who quote without analyzing your roof.
Pricing and Contracts
7. Can I see a detailed cost breakdown?
Your quote should itemize: panels, inverters, racking, labor, permitting, interconnection fees, monitoring equipment, and any additional costs. Avoid "all-in" quotes that don't break down components. Compare costs per watt across multiple quotes.
8. Are there any hidden fees or escalation clauses?
For purchased systems, the price should be fixed. For leases and PPAs, check for annual rate escalators — some contracts increase your payments 2-3% annually, which can erode savings over time. Read the fine print.
9. What financing options do you offer?
Good installers offer multiple financing options: cash, solar loans (through partners like Mosaic or GoodLeap), leases, and PPAs. They should clearly explain the pros and cons of each without pressuring you toward the option that earns them the highest commission.
Warranties and Maintenance
10. What warranties are included?
You should receive: panel product warranty (25 years), panel performance warranty (25 years, guaranteeing 85%+ output), inverter warranty (12-25 years), and workmanship warranty from the installer (10-25 years). Get all warranties in writing.
11. What happens if your company goes out of business?
Panel and inverter manufacturer warranties survive the installer's business. However, workmanship warranties may not. Ask if they have a warranty insurance policy or if warranties are transferable to a successor company.
12. Do you offer monitoring?
Production monitoring lets you verify your system is performing as promised. Most modern systems include app-based monitoring through the inverter manufacturer (Enphase, SolarEdge, Tesla). Confirm this is included at no extra cost.
Installation and Timeline
13. Do you use in-house crews or subcontractors?
In-house installation teams generally provide higher quality and accountability. Subcontracted crews can be fine, but ask about quality control measures and who is responsible if something goes wrong.
14. What is the complete timeline from contract to power-on?
A typical residential installation takes 6-12 weeks total: design and engineering (1-2 weeks), permitting (2-4 weeks), installation (1-3 days), inspection (1-2 weeks), utility interconnection (1-4 weeks). Ask for a realistic timeline specific to your area.
15. Will you handle all permitting and utility paperwork?
A full-service installer handles everything: building permits, HOA approvals, utility interconnection applications, and net metering enrollment. You should not need to visit government offices or call your utility company yourself.
Red Flags to Watch For
- High-pressure sales tactics or "today only" pricing
- Door-to-door salespeople who won't leave written quotes
- No physical office or local presence
- Unwillingness to provide references from past customers
- Quotes significantly below market rate (may indicate cutting corners)
- Requiring large upfront deposits before permitting is approved
The best approach: Get at least 3 quotes from different installers to compare pricing, equipment, and warranties. EnergySage lets you compare multiple installer quotes side-by-side for free, making it easy to evaluate your options.