Solar Panels Causing Roof Leaks (why And What To Do)

The installation of solar panels on your roof can be an exciting time as it means you will be cutting down your energy costs considerably, but doing this will involve drilling holes in your roof, which could beg the question of whether this will cause your roof to leak?

There are various reasons your roof could leak after installing solar panels. They mostly have to do with poor installation where mounting holes are not sealed properly, the top is incompatible with solar panels, or the roof is old and not designed for solar panels.

 In this article, we will cover these aspects so you will know how to avoid this happening:

  • How solar panels are installed on the roof
  • The reasons your roof could leak after installation
  • Preventing leaks from occurring

Now, let’s examine where, how, and why solar panels could cause your roof to leak.

How Are Solar Panels Installed On A Roof?

Solar panels are installed by mounting them to a racking system, which requires holes drilled in the roof to secure it.

There are several components of a solar panel installation. Aside from the electrical elements such as wiring and connection boxes, the mounting brackets holding the roof panels are a primary factor.

To install the mounting brackets, holes are drilled into the roof and usually into the rafters, and these holes are made for the lag bolts that secure the racking system upon which your solar panels are mounted.


Depending on the type of material your roof is made from, the size and depth of the holes will vary. To prevent leaks, these holes and the bolts are surrounded by ‘flashing’, a plastic or metal shield designed to prevent water from seeping into the roof.

To further seal these holes, the flashing is sealed using sealant or tar, and the holes are also sealed to provide the most waterproof seal possible and ensure you don’t have leaks once the installation is completed.

But, sometimes, all does not go according to plan, and you may suddenly find water leaking through the roof during the rainy season or when the snow melts.

See also: 13 Advantages + 5 Disadvantages Of Solar Energy

Three Reasons Solar Panels Can Cause Roof Leaks

There are three reasons your roof could leak after installing solar panels: a faulty installation, an incompatible roof, and an old one.

Faulty Installation Can Cause Roof Leaks

One of the primary causes of a leak in your roof after installing solar panels is that the installation was not done correctly. Reputable installers will work with sub-roofing materials to ensure a high-quality installation.

But where costs may be cut,  or the installer is not certified or qualified, shortcuts or lack of experience could mean you need to have some buckets laid out when the rains come.

This is why you need ONLY ever to use properly certified and qualified installers. If there is any installation issue, you have recourse for repairs that won’t cost you anything.

While we all want to save money, cutting corners on your solar panel installation can come back to haunt you later. Instead, get competitive quotes from certified installers and have a ballpark figure than taking the cheapest option.

An Old Roof Can Cause Leaks After Solar Panel Installation

If your roof is 30 years old or older, it would be advisable to have your installer thoroughly inspect it to ensure that it can withstand the weight and that the shingles have not deteriorated.

If the shingles have rotted or there are weak spots, this will increase the roof’s vulnerability to leaks as the additional weight of the panels will add stress to the structure and create gaps and holes for water to enter.

In severe cases, you may need to redo the shingles completely, and while this may incur extra and unexpected costs, at least you know that your roof will be good for another 30 years and won’t leak once the solar panel installation is installed done.

If the sub-structure is inadequate, a good installer will know how to add additional support to ensure that the weight of the panels can be held and that the risk of leaks is eliminated.

Incompatible Roof Materials Can Cause Leaks

Most modern roofs are compatible and able to withstand the installation of solar panels, but in some cases, the roof material is susceptible to leaks. If your roof is made from clay, terracotta, wood shingles, or slate, there is an increased risk of leaks developing through the installation.

While you don’t need to replace the material or completely re-shingle the roof, your installer will recommend replacing the areas where the solar panels will be installed with composite shingles.

Since composite shingles will be invisible as they are hidden away under the solar panels, there will be no impact on the roof’s aesthetics or the home, and you can rest assured that there will be no leak issues once this is complete.

How To Reduce The Risk Of Roof Leaks From Solar Panels

The best way to ensure that your solar panels are correctly installed is to hire only certified and qualified installers. If you need a roofer, try to get the same company initially installed the roof.

If this isn’t possible, check with your solar installer and have them recommend a reliable roofing contractor they use for the roofing elements if required.

Always vet your suppliers, request references, and research the company on social media and sites like to ensure you get a verified service provider.

Also, always request their certification documents and license before engaging them and verify their qualifications with the state issuing authority should you wish to go that far.

Check your warranties offered; even with the best installers, there can be problems. An installer worth their salt will have no issue providing a ten-year warranty on the installation.

What To Do If You Have A Roof Leak

While you can check the roof for debris or damage, your best bet is to call your installer immediately.

There could be any number of causes for a leak, including damage caused by walking on the roof, dragging solar panels, or having a tile break in the underlayment. These are not issues you can resolve yourself, and since your warranty would cover these issues, your first call should be to your installer.

While leaking roofs caused by solar panels are rare, taking some basic precautions before appointing an installer and having a proper and thorough roof inspection done once the installer is assigned will go a long way to reducing the risk of a leaking roof from solar panels.


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Elliot has 20+ years of experience in renewable technology, from conservation to efficient living. His passion is to help others achieve independent off-grid living.

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