5 Roof Shapes and their Compatibility with Solar Panels
How compatible is your roof for solar panels? Photo Credit: builders-directory
When it comes to collecting and converting solar energy into electricity, there are many details that enter the equation. Most of our attention focuses on financing the system, and rightly so, as that is the number one barrier to most homeowners. But beyond the barriers to adopting a solar power system are the details that will affect its performance.
High on that list is roof shape; again not usually a roadblock to installation but a factor that could affect overall performance and installation costs. Following are five roof shapes and how compatible they are with solar panel installation.
While somewhat rare on residential homes, flat roofs have to be among most installers’ favorite roofs to install upon. Advantages include safety (no steep pitches to contend with) and freedom. That freedom results from the ability to set the panels at exactly the optimal angle to the sun, achieved by building or assembling the mounting rack to exact specifications. On pitched roofs you are usually locked into whatever the pitch of the roof may be.
Gabled roofs are at their simplest level a long straight roof with one ridge line ending at high triangular walls at either end—picture the type of house most kids would draw on a piece of paper. Gabled roofs, in terms of available space, are the most compatible of pitched roofs. Often dormers or other features may be incorporated to break up the monotony of the roof, but typically gabled roofs allow plenty of space for panel installation. And if the roof, not the gable end, is facing south then that’s all the better.
Now, in discussing flat roofs there was mention of freedom to support the panels at whatever angle desired. One potential advantage of pitched roofs, such as gabled roofs, is that if the pitch of the roof is at or near optimal angle toward the sun, then installation costs may come down because the added cost of building a support structure is gone. This without sacrificing too much in system performance.
Hip roofs angle back toward a center peak on all sides. Hip roofs provide interesting roof design without much complexity. They are often combined with gables in roof design and are equally suited to solar panel installation as any other pitched roof but for one thing. By nature of their design hip roofs leave less roof space on any one side of the roof, which could limit panel installation. However, hip roofs are four-sided, compared to two-sided gable roofs (these assume the simplest of designs), so depending on the location of your home on the lot, that smaller but south-facing hip roof could come in handy.
Shed roofs are actually a type of gabled roof and are often found on dormers, over porches, or covering decks or patios. Shed roofs are characterized by a low-pitch, a slant in only one direction and are fairly easy to build. When it comes to solar panels however, shed roofs typically not too compatible. This is due to their low but angular pitch that is rarely at optimal angle. One exception may be on a barn or gambrel roof (a gable roof with two separate slopes), with a very steep slope that has a shed roof with a more moderate, workable pitched dormer built into its side. But on the whole, shed roofs tend to be simple but low pitched and thus not the most compatible with solar panels.
Octagon roofs are found on round structures such as turrets, yurts and similar designs. They have eight sides broken up into equal sections by the builder because, quite frankly, it is a lot easier to put an octagon on top of a circular frame then try to construct a circular roof. Octagons are rare but prevalent enough to warrant mention. Their main downfall in terms of compatibility with solar panels lies in their lack of consistent roof space and direction. Even if half (four sides) of the structure were facing due south, the curved nature of the roof would cause shading and poor angles of reception as each day progressed. Not that octagons are unsuited to solar panels, they are just not as compatible as other roof shapes.
What Solar Wants
It is rare that the shape of a roof will be the ultimate factor in abandoning a solar project. Even with an incompatible roof shape, you can always install a ground mount system. Furthermore, roof mounting systems are always improving in order to address those rare situations such as adjusting tilt on a pitched roof.
Furthermore, solar panel design is improving so as to reduce the need to tilt the panels at optimal angles toward the sun. They are being designed to absorb light across the spectrum and at differing intensities. What Solar wants is to be up on your roof collecting solar energy, and you can bet it will find a way if you really want it.
Roof shape may also cause variations in installation costs and materials, but remember that solar power is an investment that will start returning as soon as the panels are installed and wired in. So some extra costs for building a mounting rack or for extra labor in traversing a steep roof will be a small price to pay in the long run of free solar energy.
Find out all the specifics regarding your roof’s solar compatibility and get free estimates from our certified solar contractors.
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