Best RV Caulks: Seal and Close Gaps Permanently

Prevent leaks and water from entering your RV with these top-rated RV caulks

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If there are gaps or holes that you need to fill in your RV, you will want the strongest sealant. Properly closing up any spaces around air conditioners, vents, and windows is a great way to keep the air inside the RV and keep unwanted air out. This can also prevent water damage and block bugs from crawling their way into the camper. Check out these high-quality RV caulks if you need to seal gaps in your motorhome.

  • Best Overall
    M Marine Adhesive Sealant
    Summary
    Summary
    An extremely strong and durable solution. It’s water-resistant to keep the rain out and strong enough to be used on boats and jet skis.
    Pros
    Pros
    It’s developed with a tough polyurethane polymer to resist weathering. It can even withstand vibrations and shocks without peeling or cracking.
    Cons
    Cons
    It can take a while to dry and is not built to be used in extreme heat. While it will last through the heat, installing it in hot temps may make it thin.
  • Best Value
    Geocel Pro Flex RV Sealant
    Summary
    Summary
    The formula is crack resistant yet the solution is flexible and can fit into the smallest spaces with ease. It’s built to last up to 25 years in any weather condition.
    Pros
    Pros
    The caulk sticks to almost any surface and even works in damp, frozen, and oily conditions. It can withstand movements, bending, and bowing as well.
    Cons
    Cons
    It may shift colors with time and become more of an off-white shade. It can be a bit messy and is thick out of the bottle
  • Honorable Mention
    Dicor Non-Sag Roof Lap Sealant
    Summary
    Summary
    The caulk is reinforced to fight against the sun’s UV rays. This also prevents it from discoloring and deteriorating with time.
    Pros
    Pros
    It can be used on a variety of materials, including vinyl, aluminum, concrete, and plastic. It creates a watertight seal to protect against rain damage.
    Cons
    Cons
    It can be a pain to apply and can make a mess because you have to move quickly when applying it. The nozzle can be weak and bend as well.

Tips

  • You should wear gloves when handling caulk. The solution is sticky and can be quite messy.
  • Consider purchasing a tool to spread the caulk before it dries to help make the process easier. These tools are typically a thin sheet of plastic or rubber that repels the substance so it does not stick to it.
  • Once the caulk is dry, you can paint it to match the material it is set against to make the repair less conspicuous. 

FAQs

Q: How long will it take for RV caulk to dry?

A: This will depend on the brand of caulk you choose. It’s tough to gauge in general, but it can take anywhere from a few minutes to a full day to set up and hold.

Q: Do I have to use the entire bottle of caulk in one sitting?

A: While you do not have to use the whole bottle to seal one gap, you may want to find a reason to use it all. Once open, the compound can freeze up within a few days and make it more difficult to squeeze out. 

Q: How do I use RV caulk?

A: You simply squeeze the tube to get the adhesive out, but that may require a bit of muscle. The easiest way to apply it is by using a caulk gun. It is specifically designed to squeeze out caulk from the tube. By loading the canister into the gun, you can use the trigger to force the compound out much more simply.

Final Thoughts

To properly and permanently seal gaps and holes in your RV, consider the 3M Marine Adhesive Sealant

You can also check out the Geocel Pro Flex RV Sealant to get a tight seal that blocks out rain and keeps the air inside your RV.