Solar Readiness Check

Solar works best on an efficient home. Before you invest $15,000–$30,000 in panels, find out if your home is actually ready — or if you'd be putting solar on a leaky, inefficient foundation.

The truth about solar that no installer will tell you

Solar panels generate electricity. They do not reduce how much energy your home wastes through the building envelope. A leaky, under-insulated home needs a larger — and more expensive — solar system to offset the same bills. Many homeowners who went straight to solar found they needed more panels than expected, and still had the same comfort problems.

The right sequence is: reduce the load first — then add the source. This assessment tells you where you stand.

Your Solar Readiness Assessment

Answer 8 questions — takes about 2 minutes. No login, no email, no sales call.

Stand inside facing the street. The primary roof slope faces: (South is ideal in the northern hemisphere.)
Think about trees, neighboring buildings, chimneys, and dormers throughout the day.
A 5 kW system needs roughly 300–350 sq ft of usable roof area.
Replacing a roof under solar panels costs significantly more. Solar systems last 25–30 years.
A leaky, under-insulated home requires more solar panels to offset the same bills.
Air leakage wastes 25–40% of heating/cooling in many older homes — energy solar panels would have to replace.
Find this on your utility bill or online account. National average is ~10,500 kWh/year.
— out of 32

Factor-by-Factor Breakdown:

Recommended Next Steps:

Honest context: This assessment gives you an informed starting point — not a professional solar evaluation. A full solar assessment requires on-site shading analysis, roof inspection, utility interconnection review, and load analysis. Use this to ask better questions before you talk to any installer.

Why the Building Envelope Comes Before Solar

Solar panels generate electricity proportional to the sunlight they receive. They cannot change how much electricity your home wastes. A home that uses 18,000 kWh/year because of poor insulation and air leakage needs a solar system nearly twice the size of a well-sealed home with the same footprint and occupants.

Every kilowatt-hour you eliminate through efficiency improvements is one you don't have to generate — and efficiency improvements cost $0.05–$0.15 per kWh saved, while solar generation typically costs $0.08–$0.12 per kWh produced. Doing efficiency first makes the solar system smaller, reduces the upfront cost, and makes the economics of solar significantly better.

This is what energy efficiency professionals have known for decades. It's also what California's early programs intended before solar subsidies became politically easier to deliver than efficiency programs. The sequence is: tighten the envelope, reduce the load, then add the generation.

Common Solar Questions

What roof orientation is best for solar?

South-facing roofs at a 15–40 degree pitch produce the most solar energy in the northern hemisphere. East and west-facing roofs produce approximately 80–85% of a south-facing roof's output. North-facing roofs are generally not viable for solar in most of the US. Roof pitch also matters — very flat or very steep roofs reduce production efficiency.

How much does shading hurt solar output?

Significantly — especially with traditional string inverter systems, where shade on one panel reduces output from the entire string. Even minor shading from a chimney, vent pipe, or nearby tree can cut production substantially. Microinverters and power optimizers help, but don't eliminate the problem. Always get a full seasonal shading analysis before committing to an installation.

Should I replace my roof before adding solar?

If your roof is more than 15 years old or showing wear, yes. Removing and reinstalling solar panels to replace a roof costs $3,000–$8,000 on top of the roof cost. Solar systems last 25–30 years. A roof that will need replacement in 7–10 years should be replaced first.

What questions should I ask a solar installer?

Ask: What is the expected production (kWh/year) for this system? What is the shading analysis methodology? How was system size determined — and was it based on reducing my energy use first or just offsetting my current use? What inverter technology are you using and why? What happens to my warranty if I need roof work done? Get at least three quotes.

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