Home Solar Roof Panels: Will It Hold? Roof Size And Strength.
What’s your roof like? To be a good fit for home solar panels, your roof needs 3 things. Enough strength to hold them up, enough size to fit them all, and enough staying power to last as long as the panels will. What’s “enough?” Let’s look at some numbers. As a homeowner, you know your roof. However, you might be surprised by what it means for your solar roof panel options.
Roof Size
Most solar panels are about 3’ by 5’ in size. An average home solar installation needs about 20 of those panels. So, you’ll need at least 300 square feet of usable roof area for your home solar panels. However, the actual footprint of your roof will need to be a bit larger than that, especially if you live in California, Arizona, Utah, or another state that requires “fire setbacks.”
A fire setback code is a legal requirement that firefighters be able to get up onto your roof with designated footpaths. They’ll have that clear path in case they need to access the area for safety or rescue. Most setback codes require 3’ wide walkways around the edge of your roof. Your local solar installation company will be familiar with your region’s guidelines, but it is good to know in advance that this could come up. As a homeowner, you don’t want to be surprised by suddenly discovering that the 300 square foot roof that you thought could hold solar is too small.
Roof Strength
Each 3×5’ solar panel typically weighs about 40 pounds. To safely support solar roof panels, you’ll want a roof that can hold at least 3-5 pounds per square foot. Most modern roofs can hold up to 20 pounds per square foot safely, but if you’ve had any past issues or leaks you’ll want to flag that for your solar installation company. That way, they can help you assess if you need to do work on the roof before they add solar roof panels! For older homes or homes with unusual roofing shapes that may bear uneven weight, spending a little on roof repair before home solar installation may set you up for a low-maintenance solar system. Doing roof work now could mean a shorter road to solar savings after you install your new energy system.
Lifespan for Solar Roof Panels
The lifespan of your roof is a major factor in whether solar roof panels make sense. Even with a smaller or weaker roof, an experienced solar installation company can design a system that gives you the best solar power with the roof you have. However, there’s nothing they can do about how long your roof will be able to hold it! Your roof’s size and strength can be less important than its longevity.
A quality home solar installation can last up to 30 years. Does that mean you need to pay to put in a whole new roof before you get solar panels? There might be another option for you. If your roof isn’t in a condition to last 25-30 years, consider an alternative solar power system design instead of paying to put home solar panels onto a roof that they’ll outlast.
If you’re roof is suitable for panels, you’ll want to familiarize yourself with the three leading solar panel types and their relative efficiency, characteristics, and lifespan.
Solar Roof Panel Alternatives
While solar roof panels are the most popular form of home solar power system, there are other options. A ground mount system lets you place panels in your yard instead of on top of your house. This can offer additional square footage as well as let you aim the panels at a better direction or angle for direct sunlight. Ground-mounted panels also make it easier to expand your system if you think you might use more electricity down the road than you do right now because of a home addition or lifestyle change. Instead of having to redesign part of your roof system, you just add another panel to the yard!
Another option is to look at solar roof shingles or full solar roofing instead of roof-mounted panels. If you are already considering roof repair or replacement as part of your solar installation, these newer technologies might be a good solution. They are more expensive than the popular traditional solar roof panels but many homeowners find them more attractive because of their streamlined visual impact. Depending on the amount of wattage you really need to power your home, a few tiles could go a long way towards your home solar needs.[1]Scientific American