According to data from Consumer Affairs, the average solar installation in the US costs $20,650. In some cases, the bill can be higher than $30,000.

Although going solar leads to average savings of $125 per month on a customer’s bill, it takes years to fully recoup the cost of system installation. Therefore, making sure that your solar panel system is built to last is imperative. The longer your system lasts, the more money you save.

To get a first-rate solar installation, there are 3 key factors that you must consider. These are the building’s structural capacity, the condition and age of the roof, and electrical infrastructure integration. We’ll cover each of these in more detail below.

1) Structural Capacity

A good structural capacity analysis focuses on answering these questions: What was the original purpose of the building? How is the building currently being used? And how does this impact the planned weight for HVAC and future roof loads?

Each building is constructed with specific economic objectives. While some buildings are constructed to meet minimum code requirements, others may have been designed to accommodate heavy weight loads. These differing objectives influence the choice of beams, purlins, and structural components.

When considering the addition of solar panels to an existing building, engineers must assess how much weight can be safely added to the roof. They need to develop a solar solution that falls within the weight limit. Will the roof be able to support a racked system or a ballasted system? Does the design need to be as lightweight as possible to comply with the site’s structural limitations?

2) Condition and Age of the Roof

The condition and age of the roof are important factors to consider. For instance, in California, around 80 percent of commercial roofs are between 15 to 20 years old. At this stage, the weatherproofing of the roof is often significantly deteriorated, which compromises its ability to keep water out of the building.

It’s crucial for companies to align the lifespan of the solar system with that of the roof. If the roof is nearing the end of its life cycle, it’s not ideal to install a solar system that would need to be moved in a few years when the roof is replaced. Before installing new solar panels, it’s essential to assess and incorporate the long-term plan for the building’s roofing system.

Additionally, it’s important to consider the costs and impacts of installing solar panels in conjunction with different roof types. Various options exist for maintaining or replacing a building’s roof, with varying costs and expected lifespans.

For example, many business owners opt for membrane roofs made from TPO or EPDM rubberized polymer. These roofs offer extended durability and significant energy-saving benefits.

Understanding how to integrate solar attachments with these types of roofs without causing damage is crucial. Fortunately, there are now options available that do not require any penetration into the roof.

3) Electrical Infrastructure Integration

The electrical integration of a solar system is an important consideration. It involves incorporating the energy generated by the solar system into the existing electrical infrastructure of a building.

Commercial and industrial buildings usually have customized electrical systems designed for the original owner’s requirements. The capacity and components of the on-site electrical system directly affect the integration of new energy.

In some cases, the existing infrastructure may place limitations on the power that can be produced and integrated from a newly installed solar system.

It’s recommended to consult an experienced solar and/or electrical engineer who is familiar with code standards and has practical field experience in cost-effective integrations.


There are effective solutions for various building situations that enable companies to install the right solar system. And by getting the installation done right, you are maximizing your energy savings.