9 Best RV Caulk Out There in 2024 [Buying Guide]

Moisture is the mortal enemy of RV owners. If you have any leaks or water coming in they need to be tackled straight away. 

RV caulk is used to seal those leaks – fast. It’s really simple to use but there are a few things that you need to watch out for.

We’ve researched the market for the best RV caulk, and the best of the bunch are in our review. There is also a detailed buying guide and instructions on how to seal your RV windows and roof effectively.

RV Caulk Reviews

Dicor Self-Leveling Lap Sealant – For RV Roofs

Dicor is a well known RV brand, and this is a high quality RV roof sealant. This caulk is designed specifically for RV roofs, and will work on rubber, TPO, metal, fiberglass, aluminum, or wood. 

This is the perfect sealant for roof edges, around vent covers, vent pipes, air conditioners, and screw heads. It’s UV-stabilized to prevent deterioration and discoloration whilst on your roof.

It’s also flexible and watertight so you don’t need to worry about water getting through or breakage while being on the road.

It’s also self-leveling so you don’t need to get your hands dirty making sure the caulk is level and covering the gap completely.

Geocel ProFlex RV™ Sealant – For Everything

Another well-known and trusted brand for RV caulk is Geocel, this is a sealant that’s specially designed for RV use.

It’s more flexible than most other silicone sealants on the market so you don’t need to worry about breaks.

The tripolymer formula displaces water that might be hiding in the seams and joints you’re sealing to ensure a watertight seal. 

This caulk bonds to virtually every RV material, and is really adhesive so can seal even when damp, oily or frozen. 

It’s also mildew and UV resistant so won’t degrade even when outside in the elements 24/7, there is a 5 year warranty on the product which offers extra protection and peace of mind.

Geocel ProFlex Brushable Sealant – For Everything Exept Rubber

This is like the ProFlex RV sealant above except in a brushable format like paint. If using a caulk gun isn’t your thing then this is a great alternative. 

It’s more flexible than most other silicone sealants on the market so you don’t need to worry about breaks.

The tripolymer formula displaces water that might be hiding in the seams and joints you’re sealing to ensure a watertight seal. 

This caulk bonds to virtually every RV material, and is really adhesive so can seal even when damp, oily or frozen. 

It’s also mildew and UV resistant so won’t degrade even when outside in the elements 24/7, there is a 5 year warranty on the product which offers extra protection and peace of mind.

The only downside is that it’s not recommended for use on rubber RV roofs, unlike the tube version.

NuFlex 311 Self-Levelling RV Sealant – For RV Roofs

The NuFlex 311 Self-Leveling RV Sealant is another good RV caulk, its specially designed to be flowable so it’s one of the easiest to use.

Its formulated to work best sealing the joints when installing roof vents, air conditioning units, skylights, satellites, and more on RVs and trailer roofs. 

This sealant has excellent adhesion to most of the common materials on an RV without the use of a primer and remains permanently flexible. 

Make sure to check the weather forecast before using, as this RV sealant needs at least two hours to cure before exposure to water.

Dicor Corner Seal Kit – For Sealing RV Corners

One of the trickiest caulking jobs on RVs are around corners, if you leak is coming through a corner then you’ll need this kit.

The Dicor corner seal kit provides everything you need to get the job done! It  includes two rolls of Corner Seal Tape; six tubes of a joint filling sealant to serve as a conventional putty and cap sealant; a putty knife to remove excess sealant, and a spray bottle for the cleanup process.

If it’s a corner or small crevice that you need to seal then you can’t go wrong with this kit.

Heng’s LiquidRoofTape Liquid Seam Sealer – For RV Roofs

This is a great product, it does what it says on the tin. It’s liquid roof tape that’s a thick, high-build, rubber-like liquid consisting of 100% silicone and microfibers.

Just brush it over all entry points on the RV roof (around skylights, roof vents, plumbing caps, antennas, seams, air conditioners, refrigerator vents, ladders and roof caps). This double protects those areas where water is most likely to enter the RV. 

It is slightly expensive, but it can be as good as a new RV roof if applied correctly.

Alpha Systems Self-Leveling Lap Sealant – For RV Roofs

Alpha systems sealant is another RV roof caulk, it’s self leveling an has low VOC so you won’t need to worry about inhaling any nasty chemicals.

This sealant works on rubber, metal, or fiberglass roofs. It’s made specifically for RV roofs so can withstand the normal wear and tear that comes with being on the road. This RV caulk also designed just for horizontal applications so don’t use this on anything other than roofs.

You can also paint this once it has cured.

EternaBond RoofSeal White – For RV Roofs

EternalBond is a caulk tape for RV roofs, you don’t need any other equipment to use this and it works on most materials including EPDM, TPO, Hypalon, aluminum, galvanized steel, wood, and fiberglass.

It creates a waterproof, moisture, and air tight barrier with no additional sealing required that remains flexible. This is a great solution for RV leak repair.

Another benefit to this product is that there’s no mess because you don’t need any trays, guns or solvents to clean up.

It’s also UV resistant and requires minimal prep.

We’ve found that the tape caulk is difficult to use around corners and bends, as it’s hard to get a tight enough seal to make it waterproof. Keep this in mind if you go for this option.

Gorilla Clear 100 Percent Silicone Sealant Caulk – For Everything

The Gorilla sealant is a great cheap option for internal and window caulking. It’s great for kitchen, bath, window, doors, auto, marine plumbing, gutters, and more! 

It cures in 30 minutes and is waterproof, mold and mildew resistant, and won’t shrink or crack over time.

It can be used inside and outside, but don’t use this on your RV roof.

Picking the Best RV Caulk – Buying Guide

So, now you’ve seen our top picks you are still probably wondering which caulk is the best one for your RV. 

There are a few factors that you will want to know about before deciding which RV caulk is the best one for you. After reading this guide you’ll be well versed in the world of RV caulk and know which one will best suit your needs.

Why and What You’re Sealing

The first thing you need to consider when looking to buy RV sealant is the reason you need it, is it for a leak, maintenance, a small crack? 

Whilst you might think sealant is a sealant, there are different types. For example to seal a small crack an acrylic caulk would be best if it’s for a bigger job then a more adhesive heavy duty sealant will be needed. A brushable version might also be easier for more heavy-duty use.

You’re also going to want to know what you’re sealing, as RVs are made of lots of different materials, not all caulks work the same on these materials.

For instance, if you are sealing rubber then you’ll need a sealant that works on that material, usually a rigid acrylic caulk. But, if you’re using it on different materials like aluminum or fiberglass then that caulk would be damaging, and you’d need a sealant that can work on that correctly.

Luckily the materials for use will be clearly displayed on the packaging, so always remember to check this before using it. 

We will detail which type of caulk to use on which material later in the article.

Waterproof

You’ll want to know that your caulk is waterproof, if it isn’t waterproof then you will end up with a leak after the water soaks through. It’s a pretty important quality for a sealant to have.

Most RV caulks are waterproof and we have vetted their customer reviews and are satisfied that all the sealants in our review are waterproof when used on the right material.

Tear Resistance

Obviously you don’t want your sealant to tear, so you want to make sure your RV caulk is tear-resistant. 

It’s important to find a strong sealant with high tear resistance and will be able to withstand everything you throw at it (not literally).

Flexibility

The elasticity or flexibility of the sealant is also important, and the more flexible it is the more it can twist and turn without tearing.

The more flexibility the better! So make sure to purchase the most elastic product you can.

UV Resistance

If you’re using RV roof sealant then UV resistance is a must-have factor. You will want to know that it can hold up to sunlight and warmer weather.

If the RV caulk doesn’t have UV resistance then it will start to degrade in direct sunlight. As your RVis likely to be outside most of the time then it’s important that any repairs you do will not degrade in UV light.

Budget

Finally, we get to the price of RV caulk, not all the caulks are priced the same so you’re going to want to have a budget in mind.

Luckily RV caulk isn’t very expensive, and all the ones in the review above are reasonably priced so you don’t have to worry about paying too much.

Other Things to Know About RV Caulk

What is an RV caulk?

Caulk is a type of silicone sealant and filler that’s used to seal up and fill in cracks and gaps in walls and ceilings or for sealing joints and trims like in bathrooms. 

RV caulk has the same functionality but is more geared to sealing RV features. As RVs are always outside the RV caulk is aimed more towards external sealing, like around roof lights, etc. Thus an RV caulk can handle the outdoor environment like UV, extreme temperatures, and movement.

Because the caulk needs to be able to resist UV, water, mildew, and varying temperatures it’s important that you buy a high-quality product. The last thing you want is moisture leaking into your RV, this could be a costly mistake.

It’s also important to repeat the point made above about the different types of caulk on different materials. Make sure the type of sealant you buy is the right one for your material. We delve into this next.

What are types of RV caulks?

There are a few different types of caulks that can be used for your RV, the different types are used on the different materials. This is an important factor to know so that the caulk is effective.

Acrylic Caulk

Acrylic caulk is the most common type that you’ll find, it’s also the cheapest. Therefore it’s the most commonly used for small repairs in walls or ceilings.

USE FOR – Drywall or Wood

Silicone Caulk

Another common type of caulk is silicone, this is great to seal joints around toilets, showers and sinks. Silicone caulk is mold and mildew resistant which is great for use in the wet room.

Unfortunately, it doesn’t cope well outside, so don’t use it on the exterior of your RV because it will become brittle and degrade.

USE FOR – Interior to seal trims and joints in the bathroom or kitchen.

Vinyl Caulk

Vinyl caulk is similar to the acrylic type, but it can withstand the outdoor environment better. This would be a better choice than the acrylic caulk for exterior use.

However, it isn’t as flexible as the acrylic type so be wary of what you are sealing, if it’s prone to move then this could break the seal.

It will also be more expensive than acrylic but it will last longer.

USE FOR – Exterior cracks and gaps.

Adhesives Caulk

Adhesive caulk is as the name suggests really sticky so it will seal any material really well. You can even use this as a glue if you’re stuck for materials.

This is the best caulk for most sealant jobs needed around an RV, you can use it internally and externally. You can seal a crack and stick on whatever fell off to create the crack back on 🙂 

USE FOR – Internal, External, Fiberglass, Aluminium, Most RV jobs.

Fireproof Caulk

You can even get fireproof caulk, which as you might expect helps to prevent fire from coming into your RV. 

Hopefully, this will never be needed but if you have regular campfires or camp near anywhere that’s been affected by the recent forest fires then it’s a good idea to be extra safe and use this caulk.

USE FOR – Fireproofing

Why use an RV caulk?

So what’s the point of RV caulk? Well, that’s what we’re going to cover right now:

Seal Leaks

If you’ve read the guides then you’ll know that I have a fear of moisture invading my RV, so leaks are my mortal enemy. The main reason for RV caulk is to seal cracks that are causing leaks. 

Make sure you have a moisture meter in your RV and check around doors and windows as water can sneak through the trims. If you pick up anything up to give the seal a go-over with your caulk to stop the leaks.

Fight back against the leaks with your RV caulk! Don’t let the water in. 

Prevent Mold

If you fail to identify a leak early enough then you can easily get mold and mildew inside your RV. Because RVs are a small space then even the smallest bit of mold can be dangerous because it’s easier to breathe in when there’s not much room.

To prevent the mold you need to prevent the leaks.

Prevents Insects

Anyone who’s been RVing or camping knows that bugs get EVERYWHERE. Caulking around your windows, doors, and any gaps will help to stop them from getting in.

Some will get through though … they always do.

Prevents Debris

There is a multitude of other outside elements other than water that will want to get inside your RV. things like dust, snow, leaves, pollen, dirt, sand the list can go on.

RV caulk will help keep your RV shell secure from the litany of outside elements that want to get into your RV. If you have any cracks then you’re exposed to the outside elements, this is especially damaging if your RV is in outside storage. Imagine cleaning it and storing it for your next trip only to find mold and insects have invaded your RV.

Stop Your RVs Value Depreciating

Protecting your RV from all the factors mentioned above will help keep it in pristine condition and therefore keep it’s value. Like all vehicles, they can depreciate quickly, so keeping up with the maintenance will stop the value from going down..

It will also be more appealing to buyers and will help you sell it quicker.

How to Recaulk RV Windows?

Now we’ve run through all the reasons why you should be using RV caulk, we thought it would be helpful to run through how to recaulk your RV.

Caulking your windows is a common maintenance job for RVers, water can find its way through the smallest gaps in your windows. 

Luckily it’s not very difficult to seal up the leaks around your windows.

You Will Need

• RV caulk
• Caulking gun
• Masking tape
• Petroleum Jelly
• Ladder
• Sponges
• Cleaning Solution
• Razor blade

1 – Preparation

You will need to know where the leak is coming from, once you’ve found it the existing sealant needs to be removed. 

Use the razor blade to carefully remove the old caulk around where the leak is coming from.

2 – Clean

The area needs to then be thoroughly cleaned with a sponge and cleaning solution, this step is not to be skipped. In order for the caulk to look nice and smooth it needs to be put on a clean area.

Apply the masking tape to the areas that you don’t want caulking on, this will make the job easier and cleaner.

3 – Apply Caulk

Open the tube of RV caulk by cutting a hole in the nozzle, the wider the hole the thicker the caulk will come out. Put the tube into the caulking gun.

Grab your ladder if needed and get into a safe stable position. Pull the caulking gun trigger to put the beads of caulk around the trim of the window, taking extra care to add more where the leak is. 

When you’re happy that there is even coverage, put a small amount of the petroleum jelly on your finger. Run your finger along the bead to create a smooth finish. 

Remove the masking tape and you should have a beautifully sealed window.

How to caulk an RV roof?

Caulking the roof of your RV is just as easy as the window. Before you start, check the weather forecast and make sure that it will be dry for at least 24 hours. 

Check that the caulk is suitable for your roofing material.

1. Clean

Clean the RV roof with a sponge, soap, and water. This will let you easily see any cracks and damage, and also let the caulk set smoothly. Let the roof dry completely before the next step.

2. Find the Holes

Now the roof is clean you can have a proper look and identify any holes and cracks that might need filling. Obviously, if you have a leak start there.

3. Apply the Caulk to Your RV Roof

Open the tube of RV caulk by cutting a hole in the nozzle, the wider the hole the thicker the caulk will come out. Put the tube into the caulking gun.

Grab your ladder to get on your roof, be careful. Pull the caulking gun trigger to put the beads of caulk in and around the holes and cracks. 

When you’re happy that all the cracks are filled, put a small amount of petroleum jelly on your finger. Smooth out the caulk with your finger to create a nice finish.

Let it dry for at least 24 hours.

RV Caulk FAQs

If after reading the article you have some more questions, then don’t panic we have answered some of the most common questions here. 

Final Thoughts

So now you know everything there is to know about RV caulk. Our pick of the bunch is the Geocel ProFlex RV™ Sealant, as it will work on everything and is pretty easy to use.

As a seasoned RVer, I’d recommend keeping some caulk in your RV because you don’t want any moisture getting in!

Thanks for giving our article a read, if you have any more caulking questions let us know.