With solar panels dropping in cost and increasing efficiency, now is the time for homeowners to invest in renewable energy. On or off-grid solar photovoltaic systems can power your home reliably and sustainably for the next two to three decades. Even if you don’t have the savings to install a full solar system right now, you can at least make sure your home is “solar ready.” But homeowners have questions: what are the basic system requirements? And since most panels are installed on the roof, what type of roof works best with solar panels?
Basic Roofing Requirements
First, your home needs to be correctly oriented to take advantage of free energy from the sun. In the northern hemisphere, this means having a roof that faces south or southwest. Roofs that face north or pure east will often not receive enough direct sunlight to make solar panel installation efficient and cost-effective. Correct home orientation is also a basic tenet of passive solar design and can significantly increase the energy efficiency and thermal performance of your home.
Second, make sure that your roof does not suffer from large amounts of shade cast by neighboring homes, buildings, trees, chimneys, or other types of vegetation. If you do not have micro-inverters, consistent shading on even one of the panels can block the energy output of the entire string of panels. (If there is no way to avoid regular shading on your roof, you will want to invest in micro-inverters and bypass diodes. This minimizes the effects of partial shading by allowing the solar electricity produced in the panels to flow around the shaded panels or solar cells.)
Third, you will also want to consider the pitch of your roof. Roofs with pitches anywhere between 30 and 45 degrees will generally work well. Roofs with extremely steep pitches, such as A-Frame homes, might make solar panel installation more difficult while also compromising the efficiency of the panels. Ideally, solar panels work best when fixed to a roof angled at a degree equal to the latitude of its location. For example, solar panels installed in a home in Chicago would do best with a roof angled at around 41 degrees.
Solar Panels and Different Roofing Materials
The good news is that you can install solar panels on virtually any type of roofing material. That doesn’t mean, however, that all roofs are built alike for solar panels. Different roofing materials can lead to both positive and negative consequences that can affect the performance, cost-effectiveness, and durability of solar PV panels. Below, we look at a few of the pros and cons of installing solar panels on some of the most common types of roofing materials.
