4 Roof Damages Caused by Solar Panels (7 Ways To Avoid Them)

Installing solar panels on your roof is already a massive investment of money and time. Without mentioning all the effort in finding a good solar provider and installer. The last thing you want is to end up with a damaged roof and expensive bills on top of that. What are the damages to look out for and how to avoid them?

Solar panel installation rarely causes roof damage. These are mainly due to bad installation practices. Roof damages caused by the solar panel installation range from:

1. Broken tiles
2. Leak
3. Cracked beams
4. Structure damage

Why do these problems happen in the first place and what you do to avoid them?

To make your life easy, rather than discussing every single problem, I go through the main steps in installing a solar panel and check on each of them, what can go wrong. Indeed, leaks, for instance, can be caused by different steps in the installation.

This is important as you will give that basic knowledge to check the work of the installer. I will also provide you a quick checklist on what to ask the installer before proceeding.

Hook Installations Problems: Holes, Leaks, and Cracks

Solar panels are not drilled on the roof. They are drilled on rails that in turn are sustained by special hooks. However, what you might not know is that those hooks are not drilled on the tiles rather on the roof rafters.

Roof rafters are those wooden beans that give the shape to the roof and more importantly handle all the weight of the tiles and covering material on top.

The installer, by removing some tiles will find the rafters where to install (through drilling) the solar panel hooks.

The roof damages that can arise from the solar hook installations are broken tiles, leaking, cracked rafters, and bending rails.

1. Broken tiles: tiles that need to be removed might have been previously fixed to the roof through nails. Hence, when removing them the chances to crack and break them are very high.
   
2. Leaking: proper sealing of the holes provided. Also, for every nail removed the installer must apply roof cement to cover the hole created in the roof tar (if present). If they forget, then chances are high for water to leak through
   
3. Cracked rafter: Besides, another problem is the use of inappropriate bolts to fix the hooks to the rafters. Normal bolts are not feasible for rafters. On the other hand, roof bolts allow distributing the pressure on a wider surface (due to their large head) avoiding any crack on the wooden rafters
   
4. Bending rails: this is a fairly uncommon problem, mainly due to installers that might be new to the area. Indeed, in zones with heavy snow during winter the metal rails, if for light applications, might bend (and potentially damage the roof) if they are not able to withstand the weight of the solar panel and snow on top of them. However, a good installer should know this a priori so this should not be a real issue.

Cable Installation Problems: Leaks

Roof hooks are not the only invasive element in the roof. The cables deliver the power to your home and need to pass through the roof. Indeed, the power will arrive at an inverter (usually installed in the loft below the roof), and from there, the current will be in the right “shape” (120V phase to neutral, alternate current, 60Hz in the USA – 230V phase to neutral, alternate current, 50Hz in EU) to supply your appliances.

The power cables of a solar panel pass through the roof by either flashing (on this more on the recommendation part), passing the cable through a special plastic entry gland (a similar idea of flashing), or even just a hole with some silicon or similar waterproof material. All techniques, if done properly, and depending on the roof type, can be acceptable.

However, in passing the cable, a few things can go wrong:

1. Leaks: again, avoid flashing can be possible in relatively dry areas with clear and dry weather (such as Arizona). However, if heavy rain (Seattle) or monsoons are the norms, and the installers decide to avoid flashing and use silicon or exposed fasteners to fill the holes, the chances of future leaking are way higher
   
2. Wrong roof: these techniques (more on the advice section) is not always a solution. A solar installer friend of mine said that solar flashings are not a good practice on asphalt shingle roofs. Indeed, the break of the shingle is forbidden by the single manufacturer breaking the warranty
   
3. Wrong flashing: checking around the web I found (Alibaba) some quite cheap solar flashing in plastic. Consider that this material will stay on the roof under scorching sun, rain, snow, and all the weather problems related. Using plastic material might require replacement within 5 to 10 years
   
4. Nails and flashing: some installers place the nails on an asphalt shingle roof using nails placed too close to the edge of the flashing. Due to the position those nails get loose over time and let the water pass through the nail hole. Nails should be placed closer to the center. Possibly ask the installer to use the so-called gasketed screws. These are designed to not get lost over time.

In the above cases, drilling and sealing are involved. If the installer does not take care of this part properly or use the wrong sealant then you might have problems in the future.

Weight Problems: Cracks and Collapse

Probably this is the number one concern when installing solar panels. Are the panels going to cause the roof to collapse or crack on the wall in the house?

Solar panels are not going to cause stability problems to the house in more than 90% of the cases, especially if we are talking about residential properties (where standards are usually higher).

Solar panels are only a few centimeters thick and weigh an average of around 13kg/m2 (or 2 pounds per ft square). Each m2 provides approximately a peak power of 150W (this might vary per manufacturer but let’s take this as a good rule of thumb).

Hence, assuming an installation of 3kW, this implies you need 20 m2 of roof area for a total of 260kg (around 570 pounds). This is a lot of weight, but distributed over a large area it is not a problem for the majority of roofs.

Is your roof within this majority? Your installer must assess the property including also a deep check of your roof. If your property is not very old there are very high chances that it can withstand the solar panel weight.

However, even in the best conditions, your roof might be affected by drastic weather changes. Not talking about heavy snow but mainly sudden temperature variation. Are you experiencing cold freezing days followed by high temperatures within the next 24 hours? If so, consider reinforcing the roof.

Indeed, a phenomenon known as “diurnal drift” caused the loaded beans of roofs in the UK to crack way more often than they should do around 2012. Indeed, in cold and warm temperatures the materials tend to expand and contract at different ranges. This causes, as they are joint together, one breaks the other if these expansions happen too rapidly.

Practical Advice To Avoid Roof Damage

I want to be clear. Roof damage due to solar panel installations is virtually always the fault of the installer. As we discussed above, forgetting your local weather conditions, not using the proper material or technique depending on the roof types and age.

However, what a homeowner can do to roof damages due to solar panels? Here you can find some practical suggestions based on the real experience of several homeowners that went through the pain to deal with roof problem installations.

Remember, the majority of installers are honest and hardworking people. I know a few myself. However, there are always those that, either because of distraction, hurry or just to save money, they tend to perform poorly.

1- Take Time-Proofed Recommendations

It happens often to have at least one friend or a neighbor that just installed their solar panels and, full of their enthusiasm, they recommend the same installer.

Something great but I would not blindly go for that installer. Why? Because your neighbor or friend might have experienced good “customer service” that does not imply a good installation. In other words, the installer might have explained to them how the system worked, they showed your friend everything they needed to do in case of a problem. However, they do not have given their solar panel the time to prove that the installation was successful. Indeed, except in rare cases, any problem due to an installer not following good practices, might result in a leak, a crack, or any roof issue after a few years from the installation, not immediately.

Hence, to avoid roof damage from the incompetence of bad work, trust only recommendations for installers coming from house owners that have their solar panel in operation for at least 4 years. This will give a “time-proof” of the quality of the job provided.

2 – Check The Work

The installer might snap some pictures of the installed solar panel on your roof. You might admire the shiny silicon frame from your garden and see the inverter producing that free energy. This is good practice but it is not enough.

The second tip to avoid roof damage is to personally check, on the roof, the solar panel in presence of the installer the day the work is declared complete. You have the right to perform and ask for a visual inspection of the roof.

You must climb the metal infrastructure with the installer and inspect the roof yourself. Why? A few installers had the habits to glue pieces of broken tiles and place them back. I do not know the reason for such bad practice (probably it is faster and cheaper than installing new tiles) but this is can likely cause a roof leak in the short future.

If you do not like height or you have any mobility ask your son, relative, or neighbor.

Another tip on how to avoid roof damage is to ask the installer whether they are carrying extra tiles with them. Just warn them before signing that you will check the roof with them once the work is done and you want to see all the tiles intact. This is a good incentive for them to perform good work.

3 – Require Flashing In Wet Area

Conduit penetration flashing is becoming common practice for the majority of roofs with solar panels. Without getting into many details, these are kind of plastic or better metal covers, with a hole in the center where the cable passes through (the roof is cut in that area). Flashing is laid out either below or above the shingles and prevents water from getting in through a particular elevation of it.

Here my fourth tip.

To avoid roof damage due to solar panel installation ask the installer whether he is planning a conduit roof flashing for the cable. If the answer is negative, challenge the reason and ask for further explanations before signing any contract.

4 – Reinforce the Roof

This starts by asking yourself how old the roof is. Remember, the solar panels are going to stay there, creating an unbalanced load of a few hundred pounds (or more) for at least two decades.

If your roof is already 40 years there are very high chances that it will not last 20 years more considering also the extra solar panel load. In this case, I will consider first to go through a roof replacement.

Few people I know, especially in those 100 years old houses (the UK, Victorian houses) went through this process. You do not need to replace the roof, perhaps can be as simple as adding a few more beans.

Here then another tip. Try to find out when the roof was built and communicate this to the installer asking how long your roof can last. If he replies more than 20 years, then no need to replace or reinforce the roof. However, in other cases, you might consider if it is worth the investment of replacing the roof before.

5 – Warranty Troubles: Leak, Rodent, and Reparation Time

This is a very important topic as everything written in the solar panel installation warranty can be used in your favor (or against you). What I would like you to do is to check a few aspects (and require them if missing).

Before hiring the installer, ask them to provide a copy of the solar panel installation warranty. This will save you bad surprises in accepting a warranty after the installation is complete (that you can hardly modify or have any voice on).

Once you have the warranty on your hand, you need to check a couple of key aspects.

One of the first things to check in the solar panel installation warranty is the leak section. This should state for how long any leak caused by the solar panel installation is covered. Some installation companies, unfortunately, provide only 12 months. If so, ask for an extension of at least 3 years even if you have to pay a bit more.

Having a leak in the first year and being covered by a warranty is not enough. Indeed, a few companies (I cannot make names, but you can check them by yourself on the internet) take as long as 4 months to fix a leak on your roof. This is more likely for very large companies with a high volume of installation per day where installing a new solar panel (and getting paid) has a priority over repairing for free a roof.

Hence, another tip is to ask in the leak warranty an extra clause that specifies how long your installer will take to visit the roof and repair the problem. If possible you want this written rather than a word said by the installer. The last thing you want is to wait a few months with a leak that has the potential to damage other infrastructure of your house in the meantime. Remember, if it is not written in the warranty, by law you cannot do much (if no valid reason for serious damage to the house due to such delay).

Check if the warranty includes any rodent damage. Indeed, squirrels usually find the solar panel an ideal nest. Indeed, the space between the panel and the roof is warmer and covered from snow, rain, and intense solar heat.

Such an animal might bite the cables cutting out your solar energy production. Ask for such a warranty (or try to make some deal with the installer if you can) especially if you live close to large trees where squirrels live.

6 – Ask For The Replacement Price

Ask the installer how much it costs to remove the panels. The price might change over the years (and usually it will go up) but at least if you have an idea. It usually ranges on the $500 but it can be more.

This is important because if you have a problem on the roof that is not caused by the panel (but you need to remove them) then you need the installer for this job. Removing the panel and replacing them can be more than $1000.

7 – Roofing and Installer Companies: Troubleshooting

In case you have a leak in your roof that is not covered by the solar installer warranty if possible use the solar panel installation company to also solve the problem.

Why?

Finding who is responsible for a roof leak, especially if covered by warranty, can become hard if two companies (roofing company and installer) were involved in a very short period.

Suppose that after 6 months after removing the panel, repairing the roof, and replacing the panel a new leak appears. Who is going to be responsible for this? The solar panel installer (that perhaps made a mistake in fixing the panels) or the roofing company (that perhaps did not repair the first leak)? This can easily become a legal nightmare where the two companies blame each other and none wants to pay and you will end with a leaky roof.

In case you cannot avoid having two different companies ask the roofing company for a full report and photos of the location and type of leak. Explain to them that it is to defend yourself and them from the solar panel installer in case of any potential future problem. I guess the roofing company will be happy to provide such details if this can avoid future trouble.

After the roofing company repairs the leak, you also need to ask them to repair the area of the roof where the solar panels were removed by the solar panel installer.

Why?

The installer will very likely refuse to install the solar panels on a roof that is not in a perfect state. The holes and broken tiles left by the installer when he removed the solar panel should be fixed once the installer comes back to reinstall the panel again after the roofing company solved the issue.

The installer, if not responsible for the initial leak (repaired by the roofing company) will very likely refuse to operate in a roof that is damaged (even if they damaged it in removing the panels). This might cost as much as $500 or more.

Remember that every month your panel is not working is also energy lost that is increasing the payback time of the investment you did.

Takeaways

Solar panels are a great way to provide free energy. However, in case of a problem, it can be very expensive to repair as the roof is involved and the installer might make your life harder as free labor is always a loss for them. Hence, here a few things to remember

1. Broken tiles, leaks are the most common roof problems caused by a solar panel installation
2. Check the leak section of the warranty and the rodent section
3. Ask for timing and read the warranty before hiring the installer.
4. Installer and roofing companies have conflicting interests when a problem arises on a roof after they both operate on it. Being able to identify the responsible through adequate repairing documentation is crucial.