Qualifying Solar Leads via Roof-Area Analysis
The roof is the lead: how image analysis qualifies roof areas before outreach, and why 2,380 targeted emails create more value than 6,500 broad ones.
Flipping the funnel: the roof qualifies the lead
Classic B2B lead generation qualifies companies: industry, size, region, then outreach. In the solar business, this logic systematically leads astray, because the value of a lead depends on the property, not the company. A logistics company with 5,000 m² of flat roof is a better lead than a large corporation with a gravel roof — even though every company database claims the opposite.
The consequence: anyone generating solar leads for roof leasing or PV projects should assess the roof first and only then search for the owner. This article shows the process we use to implement that in production campaigns — from image analysis through owner research to property-specific outreach — and backs it with real campaign numbers explaining why the effort pays off. The broader solar outbound framework is covered in the article Solar sales outbound; this piece covers the step before that: property qualification.
Step 1: Assess roof areas via image analysis
The starting point is an address list — from a Maps scrape, an industry list, or geodata. For each address, an aerial image is pulled and evaluated by a vision model. What gets assessed:
- Roof area in m² — with a minimum threshold, e.g. 500 m²
- Roof type and orientation — flat, gable, or trapezoidal roof, south/east-west orientation, shading
- Condition and obstructions — air conditioning units, skylights, visible damage
The result per address: a suitability score plus an estimated yield. Both are more than a filter — they’re the raw material for later personalization. Anyone who can tell the owner how many square meters their roof has and what that means per year has a different conversation than someone who sends “photovoltaic pays off”.
Step 2: Finding the owner
Only once the property is qualified does the person research begin — in this order:
- Legal notice (Impressum) of the company website: the managing director is a mandatory disclosure there.
- North Data (northdata.de) as a commercial-register aggregator: managing directors, shareholders, history.
- Commercial register directly as a fallback.
A special case is farmers: farms often have no commercial-register entry, but do have a Maps listing with the farm name and frequently a mobile number. In that case, the channel isn’t email but WhatsApp — how that works in detail is shown in WhatsApp outreach for local businesses.
Step 3: Contact data with a routing rule
For email: legal notice and website scrape first, since for small businesses that’s often the only source. Every address gets validated before sending — in our campaigns, the bounce rate of a validated list was 0.4 percent, versus 7.7 percent for an unvalidated one. Why this decides the life or death of the sending domain is explained in the article on email deliverability.
The routing rule when both email and mobile number are available: mobile number beats email for businesses under 50 employees. On WhatsApp, the reply rate in our campaigns is around 25 percent, on email around 4 percent.
Step 4: Property-specific outreach instead of solar advertising
The image analysis from step 1 supplies the angle. The message names the concrete property and the concrete number:
“Our analysis shows your building on [street] has around [X] m² of usable roof area — equivalent to roughly [Y] € in annual lease income.”
The craft rules stay the same as for any cold-email program: under 90 words, no links in the first message, no tracking, plain text. The follow-up link — for example to an individual roof analysis — only comes in the reply to interested parties. Whoever replies gets their own roof calculated: a zero-friction entry, because the recipient can verify the image analysis result themselves.
The numbers: property qualification beats volume
Four of our own solar campaigns compared, as of June 2026:
| Campaign | Sent | Replies | Opportunities | Opportunity Value |
|---|---|---|---|---|
| Roof lease with roof analysis (production facilities) | 2,380 | 16 | 2 | six figures |
| Roof lease without property analysis (broad B2B) | 3,307 | 44 | 23 | mid five figures |
| Commercial inquiries (solar comparison portal) | 6,504 | 119 | 56 | four figures |
| Regional campaign, farmers (75 km radius) | 1,789 | 78 | 19 | low five figures |
Two patterns stand out:
- Property qualification beats volume. The roof-analysis campaign produced the highest value per email in the entire workspace with the smallest send volume. Fewer, but the right recipients — with an angle tied to their specific building.
- Regional beats national. The best reply rate (11.9 percent of contacted leads) came from the 75-km-radius campaign with a local sender reference. Logical for solar anyway: grid connection and installation radius are regional criteria.
Both patterns are expressions of the same principle: relevance over reach. This matches what we observe across channels — more in Signal-based outbound.
Who this setup is worth building
The process fits two groups: roof-lease and project developers, who want to lease or build on large roof areas — for them, image analysis is the direct lead filter. And solar installers and PV companies, who want a predictable pipeline of commercial customers — for them, the system fills the calendar. How outbound is set up for this vertical overall is shown on the vertical pages Solar and PV roof leasing.
The honest catch: image analysis, register research, validation, and sending infrastructure are four disciplines that have to mesh cleanly. GTM Goat, CegTec’s outbound system, runs exactly this process as an ongoing operation — including the campaigns the numbers in this article come from. Anyone who wants to see the system before building it: GTM Goat can be tested free for four weeks.
Common questions
Why qualify the roof instead of the company in solar B2B?
Because in the solar business, the property determines the yield, not the industry. A logistics company with 5,000 m² of flat roof is a better lead than a large corporation with a gravel roof. Anyone who first assesses the roof area via image analysis and only then researches the owner flips the classic funnel around and only addresses properties where an offer actually pays off.
What does roof-area analysis measurably deliver compared to broad outreach?
In our own campaigns, the roof-lease campaign with upstream roof analysis generated a six-figure opportunity value from just 2,380 emails sent — the highest value per email in the entire workspace. The more broadly cut comparison campaign without property analysis needed more volume for a significantly lower value per contact. Property qualification beats volume.
How does the roof image analysis work technically?
Starting from an address list, an aerial image is pulled per address and evaluated by a vision model: roof area in square meters, roof type, orientation, shading, and obstructions like air conditioning units or skylights. The result is a suitability score plus an estimated yield — and these values are later used to personalize the outreach.
How do you find the owner of a suitable roof?
In this order: first the company website's legal notice (Impressum), since the managing director is a mandatory disclosure there. Then commercial-register aggregators like North Data for managing directors, shareholders, and history, with the commercial register itself as a fallback. For farmers without a commercial-register entry, the path runs through the Maps listing, which often has a mobile number attached — then WhatsApp is the better channel.
Regional or nationwide outreach — which works better?
Regional. The best reply rate in our solar campaigns was 11.9 percent, from a regional campaign to farmers within a 75-kilometer radius with a local sender reference. Regional proximity works twice over: the sender is more credible, and grid connection plus installation radius are inherently regional criteria anyway.