Flex Seal on Camper Roof: Does Flex Seal Work on RVs?

Water leaks are the enemy. Not only to house owners but to RV owners as well. There are just so many things that can cause a leak that it seems like a never ending task to seal an RV roof. Wind, storms, debris and even small impacts can break the seal. But protecting your RV from water leaks is a job that needs to be done.

Does Flex Seal Work on RVs? Yes, it can work on your RV. The key to its successful use is to track down where the leak is and fix that spot. You should be able to stop the leaks on your RV with a little Flex seal and following the instructions.

To get all the information you need about Flex Seal and its RV use, just continue to read our article. It has the information you need to answer your questions. Getting the right information helps save you a lot of money.

Can Flex Seal be Used on RV Roofs

There should be little problem in using Flex Seal on your RV’s roof. As long as you follow the application instructions you should be able to seal up any leak on your roof with Flex Seal.

But, there is a word of warning with that. Flex Seal contains petroleum products. These products are not good with many rubber roofs or with fiberglass siding. You would need to check with an RV tech about the characteristics of your roof and see if it will be damaged by petroleum products.

Also, it may take a few months but UV rays can damage and weaken Flex Seal so it would not be a permanent fix. When you apply it to your leaky roof area, make sure you have cleaned the old sealant out, and the whole area is very, very clean. If not, Flex Seal may not adhere to the RV’s roof.

Is Flex Seal Safe for RV Roofs? (Rubber and Metal)

Not totally. Flex Seal should work fine on metal roofs. The petroleum ingredients used in creating the sealant does not hurt metal. You should be able to use this product safely when your RV is not using an alternative roofing material.

Rubber roofs are a different matter. Petroleum products tend to eat away at the rubber and cause more damage to your RV’s roof top. Safe use of Flex Seal would depend on what kind of rubber roof you have on your vehicle.

If the rubber will not be affected by the product, then it should be safe to use.. If it is affected, then you need to find a sealant that doe snot contain any petroleum in it. Don’t take a commercial or other ads word for it. Investigate first before ruining your RV and piling up the repair bills.

How to Use Flex Seal to Repair RV Roof

The cost of repairing your RV’s roof is not as much as a house roof would cost. But it is still up there and may set you further back than you wanted to be. That is why you need to find those roof leaks and patch them as quickly as possible.

The damage to your RV may not be just to the roof but to other interior parts of your vehicle. Here is how to apply Flex Seal to spare you this agony:

  • Don’t cover the whole roof- spend the time and find the leak. Patching a small portion of your roof is a lot cheaper than recovering the whole roof.
  • Clean the leaky area- you should clean it very thoroughly. Your cleaning should be better than hospital clean. Get rid of all the dirt, debris, old sealant and more.
  • Shake a lot- Flex Seal come sin its own spray can. To get it to work right, you need to shake it up and shake it up well
  • Spray the contents- After shaking, make sure to completely cover the leaky area. By the time you are done the contents of the can will be on your RV’s roof. Use more then one can if you have more leaks or a big one to seal
  • Let it dry

Flex Seal on RV Roof Seams

It is also possible to apply Flex Seal on your RV’s roof seams. The key to a proper application and a successful one is to make sure your roof seams are extremely clean. You can try the brush on version of Flex Seal but it is a black color and may not complement your roof coloring very well.

The spray version comes in a white color and should blend in with your roof color without causing any wild distractions. Flex Seal should seal up your roof seams if you follow the directions on the can and take your time.

You may need to use more than one can to make sure you have all the seams nice and sealed. This product may work even better on an old RV where the older seals are getting to the point of breaking down, cracking or falling off.

Flex Seal on RV Skylight

If you are going to use a Flex Seal product on your RV’s skylight, then you should look for the clear spray. You want to seal the skylight against any possible leaks and UV rays without blocking the light from coming inside.

The real danger in using flex seal clear is if it is like the spray on white version. The latter version can yellow and flake after being exposed to the sun’s UV rays for some time.

By using the words ‘some time’ we do not mean 4-8 hours straight but maybe 6 to 12 months of constant exposure. What some of the detractors for Flex Seal forget, is that it is not a miracle cure or sealant. It will grow old and need replacing over time. Plus, it has no real defenses from the vibration of the road.

If you need to seal the edges around the skylight’s frame, it is not hard to do. Just make sure the frame and the area surrounding it is nice and clean. Put down some tape to keep the Flex Seal from covering the wrong spot.

Next remove the old sealant completely. Then use a 45 degree angle to spray the Flex Seal around your frame, making sure you do not have any gaps when you do.

Flex Seal for RV Tank

There is some better news about Flex Seal in this section. It seems that when the product is applied properly to your black and gray water tanks, or even your fresh water one, the sealant really seals up the leak and holds for along time.

Flex Seal is designed to seep into the cracks and holes of RV tanks and then dry to a flexible but waterproof compound. After it dries, the seal should handle the vibration of the road and keep your tanks from leaking.

We should remind you that you need to check with your RV technician to see if the tank’s construction material will not be damaged if you use Flex Seal to cover any leaks.

Also, you should use a liberal amount of the sealant to make sure the crack is completely sealed up. Using a toothbrush or similar small brush should make the task quick and easy to do.

Flex Seal on RV Awning

This product is a good sealant to use when you have a water leak problem on your RV’s awning. It does a great job sealing the problem and keeping the water out. Again, the secret to this success is to follow the instructions on the can.

Now, with that said there is a slight word of warning. Awning fabric is not as thick as other materials used on your RV. What this means is that when you spray or brush on Flex Seal, you may see some bleed through and have the awning stick to itself when you go to roll it up.

One solution to this additional problem is to cute a large enough piece of clear plastic sheet off a larger section. Once that is done, you can tape this smaller section underneath the torn spot.

Then you can apply the Flex Seal and let it dry. The clear plastic sheet should stop the bleed through and keep your awning from sticking together after you roll it up. Small little tricks like this should save you from giant headaches and more costly repairs or replacements.

Flex Seal for RV Windows

Sealing your RV’s windows is like sealing your RV’s skylight. They are basically the same item and the same technique will apply. As always you have to clean out the old sealant and make sure the area around the window frame is very clean.

Then using a 45 degree angle, press the nozzle using a steady hand at the same time to move along the frame. This is just the same as using caulk and a caulk gun. Leave no gaps or air holes and let Flex Seal dry.

You can run your finger along the seal to make sure it gets into every nook and cranny along your window frame. The job is very easy to do and goes a lot quicker if you have had previous experience with regular caulk or silicone.

Flex Seal on Pop Up Camper

The rules of use for Flex Seal that apply to regular RVs will apply to your pop up camper. Proper cleaning, proper application and proper following of the instructions are vital to have Flex Seal successfully work for you.

When repairing any fabric tears or holes, just follow the tip given in the awning section. That will prevent Flex Seal from bleeding through and sticking to itself. Also, if you use your pop up camper a lot and expose those patches to the sun for along time, you may find that Flex Seal doe snot last as long as you would hope.

The results may vary and there are always mitigating factors that have Flex Seal working well for some RV users and not so well for others.

Some Benefits of Using Flex Seal

Despite the bad experiences some Flex Seal users have had, there are still some advantages to using this product on your RV or camper. There are also some disadvantages to using this product. Here is a short list of both:


  • Saves money- turning to Flex Seal can keep you from spending a lot on roof repairs that are not needed. You can spot treat leaks instead of doing a whole roof repair
  • Dries fast- in just a few minutes your rook leak is fixed and you can relax and enjoy your RV once again
  • It is everywhere- you do not have to waste time searching for it. It is a product that has a wide distribution


  • It is only a spot fix- in other words, it is not designed to cover your whole roof. The sealant works around frames, windows, awnings and a lot more but only if the area is limited in size
  • It is a temporary fix- do not expect the product to work forever. There are just too many enemies of your RV to keep that from taking place

Some Final Comments

Despite a lot of negativity towards Flex Seal, it seems to be a product that works for a large group of people. How good it is depends on the experiences of those who have tried the sealant. Those with bad experiences will say that it is a lousy product.

Those with good experiences will swear by the product and continue to use it. Your results will depend largely on how clean you get the leaky area, how well you remove old sealant and how well you apply the Flex Seal.

Then, your travel conditions will have some say in the matter as RVs tend to go through some rough roads, bad weather and so on. Your success or failure with this product depends on you.

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