You have almost finished designing your new home, most of the details have been worked out, all that is left to decide is the finishes you want to apply, and very importantly, what energy source you are going to utilize. Do you move off-grid and install a solar system or use the regular Utility power supply and leave your roof to simply function as a roof?
The decision between solar vs. regular roofs depends on cost, practicality, and environmental considerations. Solar tiles cost between 4 to 6 times more than regular roofs; however, the initial costs are offset by reduced energy costs. In every other metric, solar panels outperform regular roofs.
The advancements in solar systems, particularly solar tiles (shingles), are impressive. Most manufacturers offer solar tiles which match their conventional products. You can now choose between textures and colors, and your architect can incorporate them as part of the house’s overall design; however, how do the “new” solar panels compare to regular roofs.
Which Should You Choose, Solar or Conventional Roof?
A new homebuilder has three options when choosing a roof to install, these are:
- Regular roof, no solar and electricity is sourced from the utility
- Regular roof, with Solar Panels, installed on top
- Solar Tiles
To compare the overall cost implications of each technology, we have assumed the following:
- The house has an available roof size of 3,000ft2.
- We will install a baseline solar system generating 5kw.
- Solar tiles will require 1,000 square meters of roof
- The panel option will require 8 solar panels with a rating of 500w each. Using an average price of US$500 per solar panel, 8 * 500w Solar Panels cost US$4,000
- The average cost of conventional Roof Tiles is US$2.00 ft2
- The average cost of Solar Roof Tiles is US$14.00 ft2
The cost of the peripheral solar equipment, such as inverters and batteries, has been excluded as these are standard prices for both solar systems.
|Type of Roof||Area for Regular Tiles||Area for Solar Tiles||Area for solar panels||Total cost|
|Regular Roof||3,000 ft2||0 ft2||0 ft2||US$6,000|
|Solar Panels||3,000 ft2||0 ft2||120 ft2||US$10,000|
|Solar Tiles||2,000 ft2||1,000 ft2||0 ft2||US$18,000|
The average monthly electricity cost for a home in the United States is US$111.67. Installing an off-grid solar system will save this amount.
Applying the respective costs of both solar systems from the above table and dividing this by the saving in electricity expenses, we achieve the following breakeven points:
- Panels – 90 months (just over 7 years).
- Tiles – 161 months (just over 13 years).
If you installed a regular roof and not solar panels, a regular roof would start to cost you more after seven years. After 13 years, a regular roof would start to cost you more than solar tiles.
Solar Tiles Vs. Conventional Roofing
Each of the three options has positive and negative factors. Considering all the arguments means you can make an informed decision.
Pros And Cons Of Conventional Roofing
Conventional Roofing only serves one purpose: to cover the house and provide a protected environment for the occupants.
- Purchase and installation costs are low for this widely used material.
- The architect has greater freedom because modern tile designs offer many attractive options.
- Conventional tiles are very durable and will last for a long time through extreme weather conditions. There is more chance of the roof structure failing over time than the roof tiles.
- If the tiles get damaged, they are easy to replace with matching tiles.
- Conventional Roofing can only serve one purpose. It is essentially a passive system and can’t be adapted for other uses. Traditional tiles cannot generate energy, so the homeowner remains reliant on the grid.
Solar Tiles Pros and Cons
Solar tiles are the most advanced technology available. The list of positives is long:
- Aesthetically Solar Tiles are superior as they integrate with the roof texture and color and therefore do not compromise the roof design.
- You can install roof tiles in Intricate roof designs, which use complex hips and dormers. Solar Panels, however, can only make use of large flat areas of the roof.
- Solar Tiles are more durable than Solar Panels. Solar Tiles are designed to last 40 years, and many manufacturers provide a warranty for the entire 40 years.
- Solar roof tiles are less exposed to weather damage as the element which captures the sun’s energy is an integral part of the tile.
- Solar Tiles are easier to replace if damaged. Damage to a small part of a Solar Panel requires the entire panel to be replaced. Only the smaller damaged Solar tile needs to be replaced.
- Solar Tiles are easier to install as they integrate with the other concrete Tiles. Solar Panels, however, must be installed on top of batons (rails), which in turn must be attached to the underlying tiles or roof trusses.
- Tiles are part of the roof stricture and increase the strength of a roof.
- Solar tiles are more likely to resist nesting animals. Solar panels are an attractive location for rodents, insects, and birds to nest with all the nooks and crannies. Solar tiles don’t have this issue because they form a smooth join with the roof.
- Solar tiles are the most expensive roof option.
- Solar tiles require an area of +-200 ft2 to generate a kilowatt of energy, whereas a solar panel requires only 26 ft2 for the same amount of power; this will not be an issue if a larger roof area is available.
- It is an expensive option to increase the number of roof tiles for the future capacity growth of the solar system; this will involve removing regular roof tiles and replacing them with solar tiles.
- If the tiles are fitted to an existing roof (i.e., not a new build), the roof angles and position may not be optimum for a solar system.
Solar Panels; Good Middle Of The Road Technology
It is unfair to compare conventional roofing material with solar tiles if we don’t bring solar panels into the comparison. Although the regular roof cannot generate power, it is an excellent foundation for solar panels; thus, it is only fair to compare the benefits of installing solar panels on a regular roof.
- Solar Panels offer a more efficient energy capture per ft2 than solar roof tiles; this means that most roofs can provide sufficient space to install, at least, a rudimentary solar system.
- Solar Panels are cheaper to install than solar tiles, making the technology more accessible.
- Solar Panels are scalable. Increasing the number of solar panels over time installed on a roof is more cost-effective than adding more solar tiles.
- Solar panels can be angled to the optimum position to capture the sun’s energy.
- Solar panels, installed in a seemingly haphazard manner, are not as aesthetically pleasing as solar tiles.
- Solar panels are more exposed to damage in locations where storms and high winds are a regular occurrence. Panels can become detached from the roof during heavy storms. They will fly off the roof if strong wind causes a powerful updraft from the bottom of the rail on which they are installed.
With the continual advancements of solar generation systems, using the sun’s energy is a valid option. Not only does the homeowner move “off-grid,” but they also are making an enormous contribution to protecting the environment.
Choosing solar roof tiles over conventional Roofing is a worthwhile consideration and will see longer-term benefits for the homeowner.