Drafting general terms and conditions for solar panel companies: this is what should be included

Drafting general terms and conditions for solar panel companies involves legally covering PV-specific risks—yield forecast, roof suitability, manufacturer's warranty, and installation liability—one by one. A generic installation model rarely covers these points adequately. Below are the clauses that truly belong in them, along with the pitfalls that cost installers money if they are missing.

The short answer

1. Revenue forecast with disclaimer: indicative, no guarantee.
2. Roof suitability: who inspects the load-bearing capacity and condition of the roof, and bears the risk.
3. Warranty split: your installation warranty separate from the manufacturer's warranty.
4. Delivery and additional work: delivery moment, inspection, additional work procedure.
5. Payment: down payment, installments, retention of title.
6. Liability: limitation, exclusion of consequential damages, force majeure.

Drafting general terms and conditions for solar panel companies: the basics

Start with the standard blocks that every set of terms and conditions requires: definitions, applicability, quotation, and formation. Stipulate that the terms and conditions apply to all quotations and agreements and refer to them in your quotation. Arrange for their provision (Art. 6:233-234 BW): provide the terms and conditions before or at the time of concluding the agreement; otherwise, they are voidable.

Next come the PV-specific clauses. It is precisely these that make the difference between a set that protects you and an empty shell that lets every claim through.

Revenue forecast: the most important disclaimer

The yield in kWh mentioned in the quotation is the most common source of conflict. Therefore, document:

• The yield is a forecast based on empirical data, not a guaranteed result.
• The actual yield depends on weather conditions, roof orientation, shade, and consumption.
• You accept no liability for a lower return than the forecast.
• Any potential payback periods are indicative and depend on energy prices and net metering rules.

Without this clause, a client can hold you to a “promised” return. With the clause, a disappointing solar year is his risk, not yours.

Roof suitability and load-bearing capacity

Panels weigh weight, and not every roof can support them. Explicitly determine who is responsible for the structural assessment. The common practice is: the client is responsible for the load-bearing capacity and condition of the roof, unless you perform a structural survey as a separate service.

State that you rely on the information provided by the client regarding the roof structure, roofing material, and age. Specify what happens if it turns out during installation that the roof requires reinforcement: additional work, suspension, or termination. This prevents you from becoming liable for a roof you did not build.

Warranty: separate from installation and factory

This distinction is missing in many conditions and causes the most confusion:

• Installation warranty. Your warranty on the installation and the installation itself — an agreed period for watertightness and fastening.
• Manufacturer's product warranty. The warranty on panels, inverters, and optimizers is provided by the manufacturer, with its own terms (often both product and performance warranty).
• Passing on. Arrange to mediate with the manufacturer in the event of a product defect, but that the manufacturer's warranty conditions and terms take precedence.

This way, you prevent the customer from treating a manufacturing defect — for example, a failed inverter after years — as your shortcoming.

Delivery, additional work and payment

• Delivery. Determine when the installation is considered delivered (after assembly and operational commissioning) and which inspection is associated with it.
• Additional work. Stipulate that unforeseen extras — cable routing, distribution board, roof reinforcement — will be charged as additional work, subject to prior notification.
• Payment. Work with a down payment and a final installment after completion; state the payment term and the consequences of late payment.
• Retention of title. The panels remain your property until full payment — important in the event of the customer's bankruptcy.

Liability and force majeure

Limit your liability to a reasonable maximum, such as the invoice amount or the amount paid out by your insurance. Exclude consequential damages—think of lost revenue during downtime or damage caused by a defective inverter. For consumers, the limitation must remain reasonable; a complete exclusion will fail. Include a force majeure clause for delivery problems with panels and grid congestion at the grid operator, factors over which you have no control.

Practical example

An installer stipulates in the terms and conditions that the customer is responsible for the load-bearing capacity of the roof. During installation, the roof structure proves to be too weak. Thanks to the additional work and suspension clause, he stops the work, informs the customer, and offers reinforcement as additional work — without being liable for the delay or the structure. Without those stipulations, he would have borne the risk.

Honest recommendation

Drafting it yourself is possible if you use a reliable industry model as a basis and carefully add the PV-specific clauses—yield disclaimer, roof suitability, split warranty. For a simple company that supplies only to consumers and provides such a model properly, you often do not need a lawyer. However, if the situation becomes more complex—supplying to both consumers and businesses, yield guarantees, larger roofs, or previous claims—then a custom-drafted and legally reviewed set is worth the investment.

In-depth: view the general terms and conditions for solar panel companies, read what general terms and conditions for solar panel companies are and have general terms and conditions for solar panel companies drafted.

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