Best Types of Roof for Solar Panels
If you’ve decided to invest in solar panels for your home, you’re probably excited about the prospect of lowering your utility bills. However, you may very well have a number of questions. When speaking with homeowners considering solar panels, one of the most frequent questions is what type of roof works best with solar panels.
After all, some homeowners are concerned that their specific roof may not be a good fit for solar installation. There definitely are some types that work better than others and there are a variety of factors to consider when assessing your roof’s suitability. Let’s take a look at the best types in general as well as important factors to consider when determining your roof’s fit for solar panels.
Best Roof Types for Solar
There are a number of major types of residential roofs and while all can be utilized with solar panels, some are definitely more suitable than others. Let’s look at these types from most suitable to least suitable.
Metal roofs are very durable and environmentally friendly. They also typically outlive solar panels, which is an impressive feat. Metal roofs with standing seams are by far the best option for the installation of solar panels as standing seams make attaching the panels easy, which reduces cost. There is no need to drill holes in the roof, and the roof itself is generally a low-cost option.
Composite roofing is by far the most common type of roof for homes and typically includes either composite shingle or asphalt shingles. Fortunately, this type is also very effective for the installation of solar panels. In addition to this type of roof being more affordable and flexible in style, they are also relatively easy to mount solar panels to, and any company will have lots of experience with these types.
This type of roof can be made out of various materials including clay, ceramic, and concrete. It is another fairly common type. Solar panels on tile roofs must be attached to brackets that raise the tile. As such, the cost for installation on this type is a bit more and will vary based on the type of tile as different types require the panels to be raised at different distances.
Tar & Gravel
These roofs have interspersed layers of asphalt, tar, and supporting materials. They are relatively heavy. Most homes with flat roofs are this type. Installing solar panels on this type of roof will require additional support structure and braces, which adds to the expense. It can also be a bit difficult to conduct maintenance on solar panels on these types of roofs due to issues caused by the flatness.
This type of roof should probably have an asterisk as it can vary considerably in its setup. Wood roofs can have shingles, be angled, or be completely flat in nature. Thus, the cost to install solar panels on a wood roof will vary considerably due to many factors. The installation may be a bit difficult, which can be more expensive. However, it is doable. For people with wood roofs, comparing roof-mounted solar panels to ground-mounted systems may be worthwhile.
Factors to Consider
In addition to the basic type of roof, there are a number of different factors that should be considered to assess the suitability of a roof for solar panels and to get a sense of what the upkeep and maintenance may be for your home. Let’s look at the major factors that need to be considered when evaluating a roof.
Pitch, also known as slope, refers to the angle of a roof. Pitch can vary from flat to relatively steep. A pitch of 30 to 40 degrees is most ideal for solar power generation. If a roof has a lower pitch or is flat, the installation will require brackets to get the ideal slope which adds to the installation cost. If a pitch is steeper than 40 degrees, the solar panels won’t perform at their highest potential. Additionally, when thinking about maintenance, a higher pitch means snow will more easily slide off but that cleaning the panels may be a bit more difficult.
This essentially refers to which direction your roof faces. Living in the northern hemisphere, the goal is for a roof to face as directly towards the south as possible. This will enhance the efficiency of solar panels. However, a roof facing a different direction does not mean solar panels won’t be a worthwhile investment. Many homes with east or west-facing roofs lose less than 20% of solar panel efficiency, which is still a relatively strong output.
While one of the myths about solar panels is that they don’t function on cloudy days, shade does come into play in terms of other obstructions. It is ideal for solar panels to have direct sunlight, meaning that things like trees may affect the suitability of a roof. Fortunately, solar panel installers can usually determine some creative methods to enhance a system, even something as simple as trimming a few tree branches.
This is an important factor because solar panels can easily last 25 years. However, most asphalt shingle roofs only last about 20 years. Thus, if your roof is old, you may want to consider updating the roof before investing in solar panels. It would simply be a more cost-efficient option that would save pain later on.
This is something that people often do not think about. The size of your roof can direct your purchase though. Typically, each kilowatt of your system will require at least 100 square feet of roof space. Since most residential systems are 5 kilowatts, this means you’ll ideally have 500 square feet of roof coverage. It is also important to note that not all of a roof can be usable space. A solar installer will be able to better advise on this issue.
This was largely highlighted earlier in our article; however, it is important to note again. Solar panels can work with any type of roofing material; however, some materials will result in a higher cost due to the need for brackets, support, and other items needed to attain mounting.
Investing in solar panels is an important decision. The type of roof definitely plays an important role in how efficient solar panels will be as well as how much installation will cost. While metal roofs with standing seams make for the most efficient installation, they are not overly common. Fortunately, composite roofs and tile roofs (two of the most common residential types) are relatively good choices for solar installation.
Aside from the specific material, there are a number of other factors to consider. Typically, your roof will ideally face south, have direct sunlight unencumbered by trees, have a pitch of 30 to 40 degrees (although lower pitches can be addressed using mounting braces), not be nearing the age of replacement, and have at least 500 square feet of usable space.
If you have any questions regarding the suitability of your roof for solar panels, chatting with your local solar installer can provide more information and often find creative methods of improving solar efficiency even if a roof is not ideal.