Residential Solar Checklist
Before trusting a rooftop solar payback estimate, check whether the quote answers these questions.
Roof and site
- How much roof area is actually usable after setbacks and access paths?
- Is the roof structure suitable for the extra load?
- Are there trees, parapets, antennas, chimneys, or nearby buildings causing shade?
- What is the roof orientation and tilt?
Electrical use
- How much electricity is used during daylight hours?
- Is there time-of-use pricing?
- Will an electric vehicle, heat pump, or battery change the load profile?
Daytime consumption is a major driver of residential economics. When export compensation is lower than retail electricity, a household that can use more solar power directly will usually see better payback. Check recent bills and hourly smart-meter data when available instead of relying only on annual kWh use.
Quote details
- Does the quote include all equipment, installation, permits, and grid connection?
- What module, inverter, and racking warranties are included?
- Who handles monitoring and maintenance after installation?
- What production estimate method was used?
Financial assumptions
- What retail tariff is used for self-consumed electricity?
- What export tariff or net metering credit is assumed?
- Are incentives, taxes, loan interest, and fees included?
- What happens if production is 10 percent lower than expected?
Run a base case and a conservative case before comparing offers. A conservative case can lower production, raise maintenance cost, reduce export value, or add inverter replacement risk. If the project still looks acceptable, the quote is more resilient.
A good residential solar quote should make its assumptions clear enough that you can recreate the estimate in an independent calculator.