One of the main drawbacks of the traditional way most solar panels are installed on residential properties is that it requires drilling through the roof, which presents a few problems.
The biggest problem with drilling into the roof is that you are increasing the chance of the roof leaking. While trained and qualified installers will use sealants to minimize the chance of a leak, they do happen.
Additionally, drilling through the roof oftentimes voids the existing roof warranty.
So what are your options if you want to install solar panels on a roof without drilling?
Up until recently, the only way to install solar panels without drilling was if you had a flat roof but the good news is that a few innovative companies have created systems that let you install solar panels and don’t require drilling through the roof.
Ready to find the perfect solar system for you? Let’s find the best solution for you.
mounting Solutions for asphalt shingle roofs
There are two products that are the most similar to solar panel arrays installed via drilling that can go on shingled tiles, the Z-Rack and Flat Direct.
Both use proprietary systems to harness the wind to push the panels into the roof in high wind situations. Plus, there are two other mounting options
SolarPod Z-Rack – Aerodynamic solar Mounting
The Z-Rack is made by Minnesota-based SolarPod. Originally known as the SolarPod Crown, the patented Z-Rack technology uses a counterbalance system similar to the rear spoiler on a Formula 1 race car.
As the wind blows over the roof, it creates a downforce that pushes the panels tightly to the roof.
The system has been tested on heavy snow loads as well as at wind speeds of up to 130 MPH.
The system has been granted four patents and is UL listed. The Z-Rack system works on roofs made of shingle, wood shake, metal, tile, and corrugated metal.
While the system could be a good solution, one problem is that by trusting your roof to a single manufacturer, you could face issues down the road if the company were to close.
While the panels come with a 25-year warranty, if the company isn’t around anymore it won’t do you much good.
In this scenario, you could have a hard time finding qualified technicians to address any problems and face issues finding new panels or replacing parts.
S:FLEX Flat Direct – Weighted solar Mounting
Another option is the S:FLEX Flat Direct system. Like Z-Rack, its technology leverages the wind to push down on the panels.
The German-based S:FLEX has been in business for more than 20 years and has branches all over the world, including in Colorado.
Unlike systems that are drilled into the roof, Flat Direct maintains more gaps between panels to prevent the whole array from lifting during wind gusts.
When installed without drilling, Flat Direct uses either a counterweight or a fastening to the rafter ends to hold the system in place.
It also uses foam mats on the support posts to protect the roof as well as create friction that helps stabilize the system.
Solar Flat can usually be installed on a traditional asphalt shingled roofing, but depending on your specific roof and location, some drilling might be required.
Like the Z-Rack system, because everything comes from one manufacturer, you’ll have to hope the company stays in business.
S:FLEX is a much larger company than SolarPad so the likelihood of them staying in business is likely greater, but it is a risk.
And while the company has a US office, they are based in Germany.
With a worldwide clientele, there’s no guarantee keeping US customers happy is their top priority.
Thin-film PV solar laminates – Lightweight Solution
Another option available for no-drilling solar panel installation is thin-film PV solar laminates. This is a lightweight solution that is easy to install.
These panels are attached to the roof with an adhesive and work best on standard standing seam metal roofing panels, a durable and weather-tight roofing system.
If you are thinking of replacing your roof anyway, metal roofing combined with thin-film PV solar laminates could be a great option.
A few companies are manufacturing thin-film solar laminates, including Global Solar’s PowerFLEX+ Flexible Solar Panels.
But if you have shingles and are not in the market to replace them with a metal roof, then they aren’t a good option.
Solar Stack – Pedestal Solar Panel Mounting
Florida-based Solar Stack has been offering no-drill solar panels since 2011. Because they started the business in hurricane-plagued Florida, these panels have survived some of the strongest winds in the USA.
Solar Stack relies on a pedestal mounting system that uses a code-approved foam adhesive to create a mounting system without rails.
Foam adhesives have been used in Florida’s High-Velocity Hurricane Zone on tile roofs since 1992.
An added benefit of the Solar Stack system is that, because it eliminates drilling, installation time and costs are usually significantly less.
They come with a 20-year limited warranty.
Solar Stack works on tile, concrete decks, and structural metal sloped roofing systems.
But unfortunately, if you have a shingle roof Solar Stack is not an option.
The three solutions above are for sloped roofing. If you have a flat roof, you have a few additional options.
No-drill solar panels For flat roofs
Drilling through a flat roof is even more of an invitation for leaks. Luckily, there are a few more options for installing solar panels without drilling on a flat roof when compared to traditional sloped shingle roofing.
Here are three mounting solutions for your flat roof;
These use weights to hold the panel rack in place, particularly during heavy wind. However, this should only be done if you are sure the roof can handle the extra weight of the ballast and are allowed by your building codes.
While often a suitable solution for flat roofs, the increased weight required to keep the panels stable, particularly in windy locations, often means ballasts are a poor option.
If your area isn’t particularly windy, ballasts might be a good option.
Plates or concrete
You can install solar panels on a flat roof using heavy metal plates or concrete to hold the array in place, again provided they are permitted by your building codes.
Like other types of ballasts, metal and concrete are quite heavy, so you need to be sure your roof can handle them.
Another option is to use metal trusses that span the roof and are attached to the roof overhang to secure the solar array.
This is a good solution if the wind is an issue, however, this system has to be built specifically for your roof.
Depending on the size of the roof, the overhang, and what building materials were used, the costs of building out a suitable system could be quite hefty.
When putting panels on a flat roof, make sure the panels themselves are sloped to help keep rain and snow off.
We’ve looked at a number of solutions for putting a solar system on a roof without drilling, but before we finish there’s one more option to consider.
Stand-alone solar rack – Mounting Alternative
One last option to consider if you want solar power but don’t want to drill through your roof is not putting the panels on your roof at all.
If you have the space, you can mount solar panels on a racking system that lies on the ground instead of the roof.
This makes the system easier to work on, and could be substantially cheaper than a roof-mounted system. Especially if you don’t currently need to replace your roof.
If you have the space and the system won’t ruin your view, a stand-alone rack might be the way to go.
Mount Panels south-facing
No matter how you install the solar panels, to get the most power generation you want your panels to be south-facing whenever possible if you are in the US.
This provides the most direct sunlight for the longest amount of time. Keep in mind the more directly the sunlight shines on your panels, the more electricity is generated.
Thanks to some great products, you can have solar panels on your roof without drilling.