Can Solar Installation Cause A Leaky Roof?
As more and more of us tune into the benefits of renewable energy sources, solar panels are becoming ever bigger news. And for very good reason.
They can cut your energy bills by as much as 50 percent, reduce your home's impact on the environment, and, depending on where you live, get you a very handy tax rebate on the cost of installation.
Installation costs are getting lower by the year, and the cost of maintaining the panels is nominal.
But all of this comes with a ‘but'. To install the panels, holes will need to be drilled into your roof. Considering our homes are our biggest assets, that's a concern. Will the installation process damage your roof? Will it cause leaks?
Will you end up paying more for roof repairs than you save on energy bills? All of these questions are very normal, very common, and usually answered easily enough with a short, sweet ‘No.'
Usually. But for every rule, there's an exception, and in some very rare cases, solar panels may indeed cause damage. Here's how to avoid it.
How are Solar Panels Installed?
To understand how solar panels can, very occasionally, result in roof leaks, we first need to understand how they're installed.
Typically, the installation process will involve a racking system, wiring to connect the panels to the junction box, electrical and mechanical hardware, and of course, the solar panels themselves
During the installation, the installers will drill holes in your roof. The holes are used for lag bolts, which are designed to secure the panels to the roof. The size and depth of the holes will depend on what kind of material the roof is made from.
Deliberately creating holes in your roof might seem to be asking for trouble, but as the bolt fixtures are surrounded by flashing (a type of plastic or metal shield) to prevent water from seeping into the holes, the potential for leaks is minimal.
To further reduce the risk, the flashing is securely sealed with tar or similar material, and the hole is filled with a sealant.
Once the racking system and panels have been installed, the wiring will be used to connect the panels to an inverter to change their direct current to a usable alternating current.
If all goes to plan, leaks should not and will not occur. Does that mean they definitely won't? No. Although it's very rare, solar panels can sometimes result in damage and leaks.
Thankfully (and as we'll shortly see), that potential can easily be averted with some basic precautionary measures.
Do Solar Panels Cause a Leaking Roof?
If you've ever experienced hail or storm damage to your home, you'll understand the severity of a leaking roof.
If the problem is extensive, it can end up costing thousands of dollars worth of damage to the interior of your home, in addition to the cost of repairing the roof itself.
Being concerned about the prospect of drilling holes into your roof, then, is by no means unreasonable. Installing solar panels inevitably alters your home's structural makeup, and that's something that shouldn't be taken lightly.
But can solar panels really cause roof leaks?
The answer is…. it depends.
While the vast majority of solar panel installations are successful, sometimes, things go wrong and leaks happen. When they do, the problem usually lies in one of the following explanations.
Incompatible Roof
While solar panels can be added to almost any residential roof, some roofs are less compatible than others.
If your roof is made from wood shingles, slate, clay, or terracotta, it's at an increased risk of developing leaks and damage during the installation process.
In these cases, many solar installers will recommend replacing the areas of the roof where the solar panels will sit with composite shingles.
As the composite shingles will be hidden away beneath the panel, this will reduce vulnerability without comprising the aesthetic.
Poor Installation
The number one reason for roof leaks is poor installation. A qualified, reputable solar installer with experience in working with roofing and sub roofing material will take steps to make sure the solar panels are correctly fitted and sealed to avoid any issues down the line.
An inexperienced or unqualified installer might not. If your installer inadvertently damages the roof during the installation process or fails to ensure a tight fit, the next rain or snowstorm could bring some unpleasant surprises with it.
Old Roof
Other than poor workmanship, a major cause of roof damage and leaks are down to the roof itself. If your roof is already in poor condition, installing solar panels isn't going to help the situation one little bit.
Roofs that haven't been replaced in 30 years or more may already have several shingles that have deteriorated enough to create dry rot and soft spots in the underlying plywood and rafters.
Installing solar panels will simply add more weight and more stress to an already comprised system, resulting in an increased vulnerability to leaks.
If you have any concerns about whether or not your roof is suitable for solar panels, ask your solar installer to complete a physical inspection of the roof and its underlying structure.
If the shingles are past the point of no return, they may recommend re-shingling the roof before any further work is completed.
If the underlying structure is compromised, they'll work with you to ensure it's reinforced to the point that it can hold up solar panels without any issues.
How to Reduce the Risk of Leaks?
Certain aspects of the installation process can certainly put your roof at risk. Fortunately, it's a risk that's very easy to mitigate by hiring a certified professional and understanding the roofing requirements for solar panels.
To reduce the risk of your solar panels becoming a huge pain point, keep the following pointers in mind.
Leave it to the Professionals
Installing solar panels isn't a job that should ever be undertaken as a DIY project, and it's certainly not a job that should be put in the hands of anyone unqualified or unvetted.
Before you commit to the project, commit to finding a qualified solar installer. They'll be able to evaluate your roof, assess any potential pitfalls, and draw up a plan for fitting the panels in a way that won't comprise the structure of your home.
Avoid the Middle Man
While you're in the process of finding a professional, be wary of relying solely on roofing contractors.
Many roofers are unaware of the requirements and processes of fitting panels, and will usually subcontract the work (at added cost to you) to a licensed electrical or solar installer.
To avoid spending more than you need to (or, even worse, having the work done by a roofing contractor who's not licensed to operate in that capacity), it's worth trying to source a solar installer directly.
You'll also need to hire a roofer to handle the roofing part of the job. If at all possible, try to hire the company that originally installed the roof. Going this route, the solar installer will manage the electrical work and the roofer will handle the structural aspect of the job.
Most companies will be happy with the division of labor as it will allow them to concentrate on what they're best at – just be sure to check the cost breakdown so you have a good idea of what the bill will look like once it arrives.
Always Ask Questions
If your roof is old or otherwise incompatible with solar, a professional will be able to pinpoint and advise you on the potential dangers before you start throwing your money, quite literally, down the hole.
If you have any concerns about whether your roof is suitable for solar, ask the installer about their installation process and what measures they take to prevent roof damage.
Not only will this help elevate your worries, but it'll give you a good indication of just how knowledgeable and trustworthy the installer is.
If they seem cagey or if their answers are less than comprehensive, consider just how safe your roof will be in their hands.
If you're not quite sure what to ask, consider the following list as a template.
- Do you do the roofing work yourself or subcontract?
- What installation method do you use to attach the racking? Is it destructive (i.e. drilling through tiles) or non-destructive (i.e. the comp out method, in which tiles underneath the area the panels will be installed are replaced with composite shingles and where the racking is bolted through the new tiles into the wood heating below)?
- Will you replace any tiles that you damage during the installation process at no extra cost?
- How do you seal and waterproof the attachment points?
- Does the warranty cover roof damage, and if so, for how many years?
Ask for References
Before you commit to anything, be sure to vet your potential contractor thoroughly. Ask to see their license, search online for reviews and testimonials, and ask them to provide references from their previous jobs.
It may involve more work than simply picking the first name you find on Yelp, but putting the legwork in at the early stages will save you a lot of time, money, and leaks down the line.
Check the Warranty
Well-installed solar panels shouldn't cause your roof to leak. But problems happen. Even if you take all the necessary precautions, even if you vet the installer, and even if your roof is perfectly primed for solar installation, something may go wrong.
Usually, this will be down to poor workmanship or incorrect installation. Either way, a comprehensive warranty can make all the difference.
Regardless of who you use to install the panels, ask for details about their workmanship warranty and whether it will cover your roof if damage occurs.
Ideally, look for a 10-year warranty that will protect you against any potential issues and allow you to resolve them quickly and easily if they arise.
What Should You Do if Your Roof Leaks?
If the worst happens and your roof develops a leak, you first need to investigate whether any roofing material was damaged during the solar panel installation.
People walking on your roof can cause damage in itself; if those people are dragging solar panels around at the same time, the potential for structural damage is increased tenfold.
If a tile breaks or if the underlayment rips, then a leak can very easily occur.
Debris can also cause issues, so be sure to check in case any extraneous material has been left on the roof after the installation. You might also want to check in case any unruly tree branches are scraping against the roof and solar panels.
If you can't find an obvious and easily resolvable cause for the leak, contact your solar installer or roofer as quickly as possible after the leak is noticed. Most issues can be fixed easily enough, but the sooner you act, the better.
Be sure to check your warranty, if it's comprehensive, you shouldn't find yourself out of pocket in the event of a problem.
The Alternative Options
If you're still concerned about drilling holes into your roof, don't abandon your plans for solar just yet. Although solar panels are the most common form of rooftop solar energy, there are several other options worth considering.
One of the most popular is solar tiles, or solar shingles or solar slates, as they're sometimes known. They work on the same principle as solar panels but are made to look exactly like traditional roof tiles.
Although they're slightly less efficient and a lot more expensive than panels, solar tiles make an ideal alternative for people who are concerned about the aesthetic or structural consequences of installing panels.
Just be aware that it's not possible to simply lift a few roof tiles and replace them with solar ones.
To complete the project, the entire roof will need to be dismantled and replaced with a mixture of traditional and solar tiles. It's certainly not a cheap option, but if you've got a big budget and don't mind using it, it's worth considering.
The Bottom Line
If you're concerned about the potential implications of installing solar panels, this article isn't intended to scare you away.
In the vast, vast majority of cases, solar panels don't cause any issues whatsoever. However, this all depends on having a good installer to do the work.
A qualified, reputable installer will advise you on whether your roof is suitable for panels and, if it is, complete the job in a way that will leave you free to enjoy the benefits of solar energy without worrying about your roof springing a leak.
No matter how tempting it is to opt for the cheapest installer you can find, don't even if you save in the short term, the long-term consequences could end up costing you thousands.