Seal the Deal: A RVer’s Ultimate Guide to Choosing the Best Caulk

Last Updated March 27, 2024

Let me tell you, keeping my RV in tip-top shape is a big deal for me – it’s like caring for a member of the family! And one thing I’ve learned along the way is the importance of guarding against sneaky water damage with a trusty sealant. It’s not just about keeping the rain out; it’s about making sure my cozy little home-on-wheels is energy efficient and protected for the long haul. That’s why I’ve taken the time to dive deep into the world of RV caulks, and I’m here to share all that wisdom with you. From my favorite picks to tips on choosing the right one for your rig, find everything you need in my guide to the best RV sealants. Let’s get your RV ready for adventures galore, without any unwanted leaks!

Best RV Caulks

Best RV Caulks

I’ve been on a mission to find the absolute best RV caulk out there – believe me, it’s a jungle of choices! After diving into piles of products and testing them on my trusty motorhome, I’ve come up with a list of favorites that I just have to share with you. Whether you’re dealing with a pesky leak or just doing some routine maintenance, these top picks are guaranteed to seal the deal. So, grab a cup of your favorite beverage, and let’s walk through my handpicked recommendations together. Ready to find the perfect sealant for your road warrior?

Geocel Pro Flex RV Flexible Sealant

Geocel Pro Flex RV Flexible Sealant

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Oh, the joy of hitting the road in an RV, with the promise of adventure around every corner! But, as every seasoned traveler knows, keeping your home-on-wheels in top shape is crucial. That’s where Geocel Pro Flex RV Flexible Sealant comes into play in my life. It’s not just any sealant; it’s my go-to for ensuring my RV stays watertight and ready for whatever the road throws at it.

My first encounter with this marvel was a bit unexpected. Picture this: I was in the middle of nowhere, with the nearest RV repair shop miles away, and I discovered a leak. Panic mode? Absolutely. But then I remembered the tube of Geocel Pro Flex RV Flexible Sealant I had stashed away. It turned out to be my RV’s saving grace. The sealant’s clear appearance meant it blended in seamlessly with the rest of my vehicle, so no unsightly patches. And if I’d wanted to, I could have painted over it, but there really was no need.

What’s truly impressive about this sealant is its versatility. It bonds with almost everything – glass, coated steel, vinyl, wood, you name it. That day, I fixed a leak around my window frame, and it was as if the problem never existed. The fact that it’s designed for the great outdoors means it can handle all sorts of weather, from blistering sun to freezing temperatures, without cracking or giving way. Plus, it’s UV and mildew resistant, which means less maintenance and more enjoying the great outdoors.

Using it was a breeze, even for someone who isn’t exactly a handyman. Its flexibility forgives mistakes, and it adheres even on damp surfaces. The cleanup was just as easy, which is a blessing when you’re in the middle of nature trying to fix a leak. Knowing it has a 25-year life expectancy gives me peace of mind that’s hard to beat.

In a nutshell, Geocel Pro Flex RV Flexible Sealant has become my RV’s best friend. It’s reliable, easy to use, and it keeps my mobile abode looking as good as new. Whether you’re a weekend warrior or a full-time traveler, this sealant is a must-have in your RV maintenance kit. Trust me, it could very well turn your potential disaster into a mere pit stop on your adventure.


  • Versatility: It adheres to a wide range of materials, making it suitable for almost all RV exteriors.
  • Weather Resistance: Excellent for both hot and cold climates due to its flexibility that resists cracking.
  • Durability: UV and mildew resistance ensure the sealant maintains its integrity and appearance over time.
  • Ease of Use: Its flexibility makes it user-friendly, even for novices, and it’s easy to clean up any mistakes.
  • Longevity: With a 25-year life expectancy, it provides good value for money.


  • Exterior Use Only: Not suitable for interior use, which might require purchasing an additional product for indoor needs.
  • Limitations on Surfaces: Not recommended for use on acrylic skylight glazing surfaces, which could be a limitation for some RV owners.

This blend of features makes it a reliable choice for RV maintenance, although the limitations suggest it might not be a one-size-fits-all solution.

Dicor Self-Leveling Lap Sealant

Dicor Self-Leveling Lap Sealant

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I recently had the pleasure of tackling some maintenance on my RV, specifically aimed at those pesky leaks and seams on the roof that can turn a rainstorm into an unwelcome indoor shower. My go-to solution? The Dicor Self-Leveling Lap Sealant. Now, this isn’t just any caulk; it’s my trusty companion for ensuring my RV stays dry and cozy, no matter where we’re parked.

Picture this: I’m gearing up for a weekend getaway, and I notice a small leak that had the potential to turn my adventure into a soggy disaster. Enter the Dicor Sealant. Its self-leveling feature is a game-changer, especially for someone like me who values efficiency and effectiveness. This means no fussing over vertical seams, as it’s designed for horizontal use. Watching it slowly spread and settle into a flat, protective layer over the seam was oddly satisfying. It was like the sealant knew exactly where to go to shield my RV from water intrusion.

The versatility of this product is impressive. Whether it’s the EPDM rubber roof, vinyl, galvanized metal, wood, mortar, fiberglass, aluminum, or concrete, this sealant bonds like it’s meant to be there. Before I got started, I made sure to check compatibility – a quick step I recommend to anyone looking to maintain their RV’s roof.

My experience sealing air vents, roof edges, and screw heads was seamless, pun intended. Opting for the white shade, I appreciated how it blended perfectly with my RV’s aesthetic, but it’s great to know there are other colors available for different styles and preferences. Plus, the UV stabilization is a relief, knowing that I won’t find any unsightly discoloration or damage after a sunny trip.

Applying it was a breeze, and the fact that it becomes waterproof in just four hours was perfect timing for me. I managed to apply it right before hitting the road, and it held up beautifully against the elements. It’s a bit pricier than some other options out there, but for the peace of mind and effectiveness, the Dicor Self-Leveling Lap Sealant is absolutely worth it.

In all my travels, having a reliable, high-quality sealant like this has saved me from countless headaches. It’s not just a product; it’s an essential part of my RV maintenance kit. Whether you’re a seasoned traveler or new to the RV lifestyle, trust me, this sealant is something you’ll want to have on hand.


  • Self-Leveling: One of the standout features is its self-leveling capability, making the application process simpler and cleaner compared to non-leveling sealants. It spreads out after being applied, automatically flattening and filling in the area it’s applied to, which is ideal for horizontal surfaces.
  • Versatility: This sealant is compatible with a wide range of materials, including EPDM, TPO, and PVC membranes, and adheres well to aluminum, mortar, wood, vinyl, galvanized metal, fiberglass, and concrete. This makes it a suitable choice for various RV roof materials and other horizontal surfaces.
  • UV Stabilization: It is UV stabilized to prevent deterioration and discoloration, ensuring the sealant and the surface it’s applied to remain in good condition over time.
  • Safety: The HAPS-free formula of Dicor Sealant offers a cleaner and safer work environment, reducing exposure to hazardous air pollutants.
  • Aesthetic Integrity: It does not stain or discolor roofing materials, maintaining the aesthetic appeal of your RV.


  • Surface Limitation: Due to its self-leveling nature, it’s not suitable for vertical surfaces or edges. This limits its application to horizontal surfaces only, so you might need a different product for vertical seams or repairs.
  • Curing Time: While it becomes waterproof relatively quickly, the full curing process can take up to 30 days. During this time, it’s important to check weather conditions and ensure the sealant has ample time to cure fully without being disturbed by heavy rain or debris.
  • Cost: Compared to some other caulks and sealants on the market, Dicor Self-Leveling Lap Sealant might come at a premium. However, the quality, effectiveness, and specific design for RV use justify the investment for many RV owners.

In terms of personal experience and recommendations from industry experts, Dicor products are widely used by RV manufacturers and recommended by RV technicians for their reliability and effectiveness in sealing and protecting RV roofs from water damage. The brand’s focus on creating products tailored for RV maintenance, including the distinction between self-leveling and non-leveling products for different applications, highlights their commitment to meeting the needs of RV owners.

Sashco Clear Lexel Adhesive Caulk

Sashco Clear Lexel Adhesive Caulk

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Oh, the joys of RV life – the freedom, the adventure, and, let’s be honest, the occasional leak that threatens to dampen the whole experience. That’s where my trusty tube of Sashco Clear Lexel Adhesive Caulk comes into play. Picture this: a sealant so versatile that it has become my go-to for just about every sealing need on my RV, both inside and out. Whether it’s securing the area around my shower to keep water where it belongs or ensuring my side vents are airtight, this transparent copolymer rubber caulk has got it covered.

I remember the time I discovered Lexel Adhesive Caulk. It was almost by accident, really. I was browsing through a store, looking for something that could adhere to the unique materials of my RV. And there it was – claiming compatibility with an array of materials like metals and plastics, which was exactly what I needed. But what truly sold me was its promise of flexibility and its waterproof nature right upon application. I thought, “This sounds too good to be true,” but gave it a shot anyway. And boy, am I glad I did!

Applying it was a breeze, and the fact that it can be used in the pouring rain was a game-changer for me. You know how unpredictable the weather can get when you’re out exploring. Plus, the fact that it doesn’t freeze meant I could use it even during those chilly early spring or late autumn adventures without a hitch.

I was initially a bit skeptical about the claim that it stays clear and doesn’t yellow over time, especially with my RV being constantly exposed to sunlight. But true to its word, Lexel has maintained its clarity, making it practically invisible wherever I’ve used it. It’s also withstood the test of time against the abrasive cleaners I use in the kitchen and shower, still holding strong without a sign of wear.

But, a word to the wise – while it’s a champion on most materials, rubber and polystyrene foams are its kryptonite. I learned that the hard way on a minor project, but it was a small hiccup in an otherwise flawless performance.

In my book, if you’re looking for a reliable, flexible, and truly multi-purpose RV sealant that won’t break the bank, Sashco Clear Lexel Adhesive Caulk is the way to go. It’s not just a product I use; it’s become a staple in my RV maintenance kit, ensuring that my home-on-wheels remains snug and dry, no matter where I park it.


  • Versatility and Compatibility: The Lexel Adhesive Caulk shines when it comes to adhering to a wide array of materials. Whether you’re working with metals, plastics, or wood, this sealant is up for the task, making it ideal for a range of RV sealing projects both inside and out.
  • Weather Resistance: It’s waterproof immediately upon application, doesn’t freeze, and sticks to wet surfaces. This feature is particularly handy for repairs in less-than-ideal weather conditions, ensuring your RV is protected against water damage no matter where you are.
  • Durability: The sealant boasts impressive flexibility, handling up to 400% joint movement without losing its effectiveness. This flexibility is critical for the moving parts of an RV, where materials can expand, contract, and shift during travel. Moreover, it stays clear even with UV exposure, avoiding the yellowing that can happen with other sealants.
  • Ease of Use: Lexel Adhesive Caulk is lauded for its straightforward application process. It can be painted over, allowing for a seamless blend with your RV’s aesthetics. Its ability to stick to wet surfaces and remain waterproof and freeze-resistant upon application makes it a reliable choice for immediate repairs.


  • Limited Compatibility with Certain Materials: Despite its broad compatibility, Lexel Adhesive Caulk doesn’t bond well with rubber materials or polystyrene foams. This limitation requires users to double-check compatibility with their specific project materials before use.
  • Cleanup Considerations: Like many sealants, Lexel can be messy to work with, and cleanup requires more effort compared to some other caulks. It’s important to plan for this to avoid sticky situations during application.

Given its many advantages, including versatility, durability, and ease of use, Sashco Clear Lexel Adhesive Caulk stands out as a top contender for RV maintenance. However, it’s essential to weigh these benefits against the few drawbacks, like its incompatibility with certain materials, to ensure it meets your specific needs. Whether sealing leaks, weatherproofing windows, or undertaking general maintenance, Lexel offers a robust solution for RV owners looking to protect their home on wheels.

3M Marine Adhesive Sealant Fast Cure 4000 UV

3M Marine Adhesive Sealant

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I recently had the chance to use the 3M Marine Adhesive Sealant Fast Cure 4000 UV on my own RV, and let me tell you, it was an experience worth sharing. If you’re in the market for an RV caulk that really holds its own against the sun’s harsh rays, you might want to give this product a closer look. It’s been a game-changer for me, especially considering the high UV resistance it offers.

This sealant is something of a marvel; it creates a medium-strength bond that’s not only robust but also forgiving enough for easy disassembly, which is a rare find. The waterproofing capabilities are top-notch, ensuring that whatever you seal is going to stay dry, come rain or shine.

One of the biggest selling points for me was its versatility. Whether you’re working with aluminum, gelcoat, wood, or fiberglass, this silane-modified polymer is up to the task. I found it incredibly reassuring to know that I was applying something that could withstand the elements, especially given the harsh conditions my RV often faces.

Another feature that stood out to me was its paintability right after application. This is a big deal if you’re looking to maintain a cohesive look on your RV’s exterior. Many sealants require a waiting period before painting, but not this one. You can apply it and paint over it immediately, ensuring a seamless finish.

When it comes to durability, the 3M Marine Sealant really shines. It’s designed to absorb the shocks and strains of road life, from vibrations to the expansion and contraction caused by temperature changes. This flexibility means it’s less likely to crack or degrade over time, protecting your RV from UV damage, weather, and the rigors of travel.

Now, it’s worth mentioning that this sealant is on the pricier side. However, in my view, the cost is justified by its performance and longevity. It might also present a bit of a learning curve if you’re new to using these types of products. But with a little patience and practice, I found that applying the sealant became second nature. Plus, its ease of removal for repairs or adjustments is a huge bonus.

In conclusion, if you’re after a reliable, durable, and UV-resistant sealant for your RV, the 3M Marine Adhesive Sealant Fast Cure 4000 UV is an excellent choice. It’s helped me ensure my RV stays in tip-top shape against the elements, and I’m confident it can do the same for you.


  • High UV Resistance: This sealant is particularly noted for its exceptional UV resistance, making it an excellent choice for applications exposed to sunlight.
  • Versatile Application: It works well on a variety of surfaces including aluminum, wood, fiberglass, and gelcoat, providing flexibility in use across different materials.
  • Easy Application & Cleanup: Many users found the application process straightforward, and appreciated the ease of cleanup. Plus, a little goes a long way, adding value to each purchase.
  • Durable & Waterproof: It offers a firm, rubbery, waterproof seal that stands up well to the harsh marine environment, ensuring longevity and reliability.
  • Paintable: It can be painted over immediately after application, allowing for seamless integration with the rest of the vehicle or vessel.


  • Curing Issues: Some users reported issues with the sealant not curing properly, remaining sticky, or becoming chalky and cracking over time.
  • Nozzle Not Included: A few customers were disappointed that the product did not come with an application nozzle, which they felt was needed for easier application.
  • Yellowing and Mildew: There were reports of the sealant turning yellow and mildewed/moldy within a few months of application, particularly when exposed to water, which is a concern for a product designed for marine environments.
  • Cost: It is noted to be more expensive than many other sealants on the market, which could be a deciding factor for some buyers.

Despite a few drawbacks, the 3M Marine Adhesive Sealant Fast Cure 4000 UV remains a popular choice for many, offering a strong, flexible, and UV-resistant option for RV and marine applications. Like any product, individual experiences can vary, and it might be beneficial to consider how the sealant’s characteristics align with your specific needs and application conditions.

Camco Pro-Tec Self-Leveling RV Roof Sealant

Camco Pro-Tec RV Roof Sealant

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Embarking on a journey with the Camco Pro-Tec Self-Leveling RV Roof Sealant was an adventure in RV maintenance I didn’t know I needed. As someone who’s always on the lookout for the best RV caulk to ensure my mobile abode remains in tip-top shape, I’ve encountered my fair share of sealants, but the Pro-Tec sealant stood out for several reasons.

Firstly, the application process was a breeze. Designed for horizontal applications, its self-leveling feature meant I didn’t have to labor over getting the perfect finish – the product did the heavy lifting for me. Its formulation is suited for 1/4-inch and 3/8-inch beads, making it versatile for different sealing needs around the RV’s roof edges, vent pipes, or air vents.

What impressed me most was its compatibility with a wide range of materials. Whether it’s EPDM rubber, TPO, fiberglass, wood, aluminum, steel, or masonry, this sealant adheres with ease, creating a durable barrier against the elements. This adaptability makes it an essential tool in any RV owner’s arsenal, especially for those of us who relish the idea of being prepared for any repair scenario.

Moreover, the peace of mind that comes with using a product designed to withstand harsh conditions cannot be overstated. Knowing that my RV is protected with a strong, reliable seal makes all the difference when facing unpredictable weather during my travels. The user-friendly tube design further simplifies the application process, ensuring that even novices in RV maintenance can achieve professional-level results.

In the realm of RV caulks, the Camco Pro-Tec Self-Leveling Roof Sealant certainly earns its place at the top. Its ease of use, compatibility with various materials, and the strong seal it provides make it a standout product. Whether you’re a seasoned RV enthusiast or just starting out, this sealant is a must-have for ensuring your vehicle’s longevity and reliability.


  • Wide Compatibility: The Camco Pro-Tec Sealant is designed for a variety of materials, including EPDM rubber, TPO, fiberglass, wood, aluminum, steel, or masonry. This versatility makes it suitable for almost all types of RV roofs and other horizontal applications.
  • Self-Leveling Feature: This feature simplifies the application process, ensuring a smooth, even seal without the need for extensive manual smoothing or adjustment.
  • Ease of Application: Its formula and tube design cater to DIY enthusiasts and professionals alike, allowing for straightforward application. This aspect is particularly helpful for those new to RV maintenance or sealant application.


  • Drying Time: A thicker application of the product may lead to longer drying times. This can be a drawback if you’re in a hurry or if the weather conditions aren’t ideal for a slow drying process.
  • Removal Difficulty: If mistakes are made during application, the sealant can be challenging to remove. This makes precision important during use.

For fellow RV owners in pursuit of the best RV caulk, I cannot recommend the Camco Pro-Tec Self-Leveling RV Roof Sealant highly enough. It’s not just a product; it’s an investment in the safety and durability of your home on wheels.

RecPro 1021 Self-Leveling RV Roof Sealant

RecPro Self-Leveling RV Roof Sealant

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I recently had the chance to put the RecPro 1021 Self-Leveling RV Roof Sealant to the test on my motorhome, and let me tell you, it was a game-changer. My RV, like many out there, sports a Superflex roof by Alpha Systems, along with the typical EPDM rubber roof sections. Finding the right products to maintain and protect it can be a bit of a challenge, but the RecPro 1021 came through with flying colors.

First off, the thing to know about this sealant is that it’s perfect for flat surfaces. Whether you’re dealing with pesky leaks around pipes and vents or just want to give your entire roof a once-over, this sealant has got your back. However, it’s a self-leveling type, which means it’s not suitable for vertical applications. So, for those areas, I had to look for a different solution.

One of the aspects I absolutely love about this product is its flexibility. We’ve all been there, cruising down the highway when suddenly you hit a pothole the size of a crater. The RecPro 1021 is designed to handle that kind of shock and vibration without cracking or deteriorating, which is peace of mind you can’t put a price on. Plus, it can withstand extreme temperatures, both hot and cold (we’re talking a range from -65 to 250 degrees F!), and is completely weather-resistant.

But here’s the kicker – it’s also resistant to chemicals, greases, oils, salt, and fuel. I accidentally spilled a bit of oil on the roof during a maintenance day, and I was amazed to see that the sealant didn’t show any signs of damage. It’s this kind of durability that makes the RecPro 1021 a staple in my RV repair kit.

For those who are particular about aesthetics, it dries white but can be painted over to match your RV’s specific color scheme. I haven’t felt the need to paint mine yet, as the white finish actually looks pretty sleek against my RV’s design.


  • All-Weather Resilience: It stands up well in both extreme heat and cold, ensuring your RV remains leak-free for years.
  • Self-Leveling: The sealant spreads out on its own for quicker roof sealing, making application easier without the need for brushing it even.
  • Versatile: It works as a multi-purpose adhesive, suitable for various sealing tasks on your RV’s roof.
  • Color and UV Resistance: Dries completely white and maintains its color without turning yellow, even after prolonged exposure to sunlight.


  • Temperature Sensitivity for Self-Leveling: The sealant’s self-leveling property may not function properly in cold conditions. It’s recommended to apply it on a warm and sunny day to ensure it spreads and flattens as intended.

In my experience, whether you’re looking to fix a specific leak or preemptively protect your roof from potential damage, this sealant is incredibly easy to use and offers great longevity. It’s become my go-to, not just for its performance but also for its affordability. For anyone with a TPO or EPDM roof, I can’t recommend the RecPro 1021 enough. It’s a small investment that pays off big time in protecting your home on wheels from whatever the road throws at it.

Gorilla Waterproof Caulk & Seal 100% Silicone Sealant

Gorilla Waterproof Caulk

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After spending considerable time with the Gorilla Waterproof Caulk & Seal 100% Silicone Sealant, I must say, it’s a game-changer for anyone with an RV. I’ve always been on the lookout for reliable, durable caulking solutions to ensure my RV remains in top shape against the elements, and this product has lived up to its promises splendidly.

First off, the application process is a breeze. Whether you’re sealing around windows, doors, or patching up some unexpected leaks, the sealant flows smoothly and adheres firmly. The fact that it’s ready for water exposure in just 30 minutes is a massive plus for those times when you’re caught off-guard by the weather. And believe me, when you’re out in the wilderness, that’s a common occurrence!

One of my main concerns with any sealant is longevity and maintenance. The Gorilla Silicone Sealant shines here as well. It’s not only mold and mildew resistant but also doesn’t yellow, shrink, or crack over time. This durability means you’re not redoing the same sealing job every few months, a common annoyance I’ve had with other products.

Additionally, it’s designed for both indoor and outdoor use, making it incredibly versatile for all your RV needs. From the bathroom to exterior joints, it provides a 100% waterproof seal that stands up to both high and low temperatures, which is essential when you’re dealing with a variety of climates.

However, it’s important to note a few caveats. The sealant isn’t paintable, so make sure you choose the right color for your job—thankfully, it comes in both clear and white options to match most needs. Also, it’s not suitable for use on wet, damp, frozen, or contaminated surfaces, which requires a bit of planning to ensure the area is prepped and ready for application.

To sum up, the Gorilla Waterproof Caulk & Seal 100% Silicone Sealant has become my go-to for all RV caulking projects. It offers ease of use, durability, and the flexibility needed for the varied tasks involved in RV maintenance. Whether you’re a seasoned RVer or just starting out, this product is a worthy addition to your maintenance toolkit.


  • Versatility: The Gorilla Sealant works well on almost any surface, making it an excellent choice for a wide range of projects, from bathroom repairs to outdoor sealant needs. This flexibility is a significant advantage for RV owners who might need to address various materials and conditions.
  • Durability and Waterproof: It’s incredibly durable and completely waterproof, capable of withstanding harsh weather and moisture, ensuring that areas sealed with this product remain tight and leak-free.
  • Resistant to Mold and Mildew: This product is resistant to weather, moisture, and consequently, mold and mildew. This feature is especially beneficial for applications in moisture-prone areas like bathrooms and kitchens in your RV.
  • Clear Drying: For aesthetic considerations, it dries clear, leaving no noticeable residue. This feature is particularly appealing for jobs where the sealant might be visible and where a clean, unobtrusive finish is desired.


  • Not Ideal for Wood: The sealant is not the best choice for wood surfaces. If your project involves sealing or bonding wood, you might need to consider alternative products specifically designed for wood or use it in conjunction with Gorilla Wood Glue for optimal results.
  • Requires Solvent for Removal: Unlike some sealants that can be cleaned up with water, this silicone sealant requires a solvent for removal. This might necessitate extra precautions and additional products for cleanup, especially if you’re working in a confined space or need to correct a mistake.

Given these points, the Gorilla Waterproof Caulk & Seal 100% Silicone Sealant stands out as a robust, versatile option for a wide range of sealing tasks, particularly in scenarios that demand waterproofing and durability against the elements. Its few downsides, such as its performance on wood and cleanup requirements, are relatively minor and can be managed with proper planning and application techniques. This makes it a strong contender for inclusion in your RV maintenance toolkit, ensuring that your vehicle remains protected against leaks and moisture intrusion.

Sashco Through The Roof Sealant

Sashco Through The Roof Sealant

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Embarking on adventures in my RV, I’ve encountered my fair share of unexpected challenges, especially when it comes to maintenance. That’s why I’m always on the lookout for reliable, cost-effective solutions that keep my home-on-wheels in top shape. One of my go-to products for ensuring a dry and secure environment inside my RV, regardless of the weather outside, is Sashco’s Through The Roof Sealant. Trust me, this gem offers some serious bang for your buck, especially when you snag it in the six-pack offering.

Here’s why I’m such a fan: its co-polymer rubber formula creates an almost invisible seal that’s incredibly durable. Whether I’m dealing with minor roofing panel replacements or tackling leaks around the vents, AC unit, or skylights, this sealant has been my saving grace. It’s impressively versatile, bonding flawlessly with a wide array of materials like fiberglass and plexiglass, ensuring a permanently elastic roof seal that can withstand the elements.

Now, I should mention it’s not the best match for polystyrene insulation projects. But in terms of weather resistance, it’s a stalwart defender against water damage, keeping my motorhome snug and dry even in the most challenging conditions.

Admittedly, its temperature range – staying solid from 0 to 120 degrees F – might not cater to those who venture into extreme climates. However, for someone like me, who sticks to relatively temperate zones, it’s been a perfect fit. Its efficacy on wet surfaces also means I can address leaks promptly, preventing any potential long-term damage without breaking the bank.


  • Easy to apply and works on a variety of surfaces, including RV roofs and chimneys.
  • It’s durable, long-lasting, and remains clear once applied, blending seamlessly with the surface.
  • Notably effective for emergency repairs, providing a strong hold even in harsh weather conditions.


  • While it offers good value, it is priced higher than some alternatives. However, its quality and longevity justify the cost.
  • The curing process can take up to a week, so patience is required for it to fully seal.
  • It’s recommended to remove any silicone on the surface before application, which could add an extra step in preparation.

The value pack has been a real wallet-saver, too. Finding a product that delivers such reliable performance at a low cost per cartridge felt like hitting the jackpot. So, if your RV travels don’t take you to the extremes of the thermometer, Sashco’s Through The Roof could very well be the trusty sidekick your motorhome needs.

Sashco Big Stretch Caulk

Sashco Big Stretch Caulk

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When it comes to maintaining my RV, I’ve run into my fair share of challenges, especially when dealing with pesky leaks along the sides. That’s when I stumbled upon Sashco’s Big Stretch Caulk, and let me tell you, it’s been a game changer. Not just any caulk, this one boasts an incredible ability to stretch over 500% of its original size. For someone who was tired of the endless cycle of re-caulking a stubborn leaking vertical seam on my motorhome, discovering this product felt like hitting the jackpot.

Crafted for both indoor and outdoor use, the Big Stretch Caulk features a highly elastic, no-crack formula that’s perfect for sealing around windows, doors, slide-outs, and side vents. What I appreciate most is its versatility; it adheres to a vast array of materials. However, a quick tip: always double-check its compatibility with your RV to ensure a seamless application. It’s noteworthy to mention that this isn’t your go-to for roof repairs, but it excels in virtually every other aspect.

One of the standout features for me has to be its UV resistance. The durability of this caulk means I can set it and forget it, without worrying about replacements due to cracking. Plus, it comes in clear for an unnoticeable finish, or you can choose a color that complements your RV. And if you’re particular about aesthetics like I am, you’ll be glad to know it’s paintable for that perfect match.

As someone who spends a considerable amount of time in my RV, I also appreciate that this caulk is low-odor—a rare find among RV caulks. It’s especially handy for those of us who live in our motorhomes full-time and are sensitive to strong smells. The easy cleanup is another bonus. I remember one time I applied it a bit messily, but tidying up was a breeze, sparing me hours of frustration.

The Big Stretch Caulk isn’t just another addition to your RV maintenance kit; it’s a high-performance, ultra-stretchy solution for any join along your rig’s sides. Offering a waterproof and weather-proof seal that withstands the test of time, its high level of UV and temperature resistance means you’re getting quality protection against the elements. If you’re on the lookout for a reliable, flexible sealant for your RV, based on my experience, Sashco’s Big Stretch Caulk is definitely worth considering.


  • Flexibility and Elasticity: One of the most lauded features of Sashco Big Stretch Caulk is its exceptional ability to stretch more than 500% of its original size, which makes it particularly effective for areas prone to movement or expansion. This attribute ensures a durable, long-lasting seal that can accommodate the natural shifts within an RV’s structure.
  • Wide Range of Applications: This caulk is suitable for both interior and exterior use, including around windows, doors, slide-outs, and side vents. It adheres well to a variety of materials, making it a versatile choice for different surfaces within your RV.
  • UV and Weather Resistance: The high UV resistance of this product means it’s less likely to degrade under sunlight, extending the life of the caulk. Its weather-proof properties ensure a seal that can withstand various environmental conditions without cracking.
  • Low Odor and Easy Cleanup: Unlike many sealants that emit strong odors, Big Stretch Caulk is low-odor, making it a more pleasant option for use in confined spaces like RVs. Additionally, its ease of cleanup is a significant advantage if adjustments are needed post-application.
  • Mildew Resistance: An important feature for maintaining the aesthetics and healthiness of your RV is the caulk’s resistance to mildew, which prevents the appearance of unsightly black spots in damp conditions.


  • Not for Use on Roofs: While Big Stretch Caulk offers wide-ranging applicability, it’s important to note that it’s not intended for use on roofs, limiting its versatility in some RV maintenance tasks.
  • Longer Drying/Curing Time: Compared to some other caulks, Big Stretch has a longer drying and curing time. It may take 4 to 5 days to fully cure, which could be a drawback for those needing a quicker turnaround.
  • Limited Waterproofing in Prolonged Dampness: Although Big Stretch Caulk has good resistance to moisture and chemical effects, it might not be as effective in situations of prolonged dampness or for applications requiring submerged water resistance.

In summary, Sashco Big Stretch Caulk stands out for its flexibility, durability, and ease of use, making it a strong contender for a variety of RV maintenance needs. However, its longer curing time and limitations regarding roof use and prolonged water exposure are points to consider when deciding if it’s the right product for your specific requirements.

My Ultimate Guide to Choosing the Perfect RV Caulk

Why Settling for Less Could Cost You More

You know how they say, “Buy cheap, buy twice”? Well, they were definitely talking about RV caulk. I learned the hard way that skimping on quality to save a few bucks just isn’t worth it. Choosing a top-notch sealant is crucial for keeping your RV safe from the elements – because, trust me, re-caulking is no picnic. And if water damage gets its way? Hello, hefty repair bills! So, take it from me: invest wisely in your RV’s protection.

Sunshine and Sealants: The Battle Against UV

Let’s talk about the sun – our friend, but not when it comes to caulk. Some caulks just can’t stand up to UV rays and start cracking or yellowing faster than you can say “road trip.” I always look for something that promises high UV resistance. It means less re-caulking and more enjoying my RV without worrying about leaks or an unsightly finish.

Water, Water, Not Everywhere

Waterproof might seem obvious for caulk, but you’d be surprised! Not all sealants are ready to take on water from day one. And when you’re caught re-caulking in the rain (been there, done that), you’ll wish you had a sealant that sets instantly, even on wet surfaces. Trust me, choosing a fully waterproof caulk from the get-go can save a ton of hassle.

Bend, Don’t Break: The Flexibility Factor

Life on the road means dealing with all sorts of temperature changes and vibrations, which can really test your caulk’s durability. I always opt for something that stays flexible, ensuring that it keeps the seams sealed tight, no matter what. The last thing you want is for your caulk to give up on you because it can’t handle a little movement.

Tough as Nails: Why Tear Resistance Matters

Especially around parts of your RV that move a lot, like slide-outs, you need a caulk that’s as tough as nails. High tear resistance means it won’t snap under pressure, keeping everything sealed and secure.

Seal the Deal: Knowing What You’re Working With

Not all caulks are created equal, and not all will work for every job on your RV. Doing general maintenance? A versatile multipurpose caulk is your best friend. Working on the roof? You’ll want a self-leveling caulk that smooths itself out for a perfect seal every time – but remember, it’s not for vertical surfaces. And for those windows and doors? Grab a caulk that’s made for the job, ideally something super flexible to cope with all the opening and closing action.

Lastly, always double-check that your chosen caulk is compatible with your RV’s materials. A quick call to the manufacturer can save you a world of trouble.

Navigating the World of RV Caulks: Types of Caulk

Finding the right caulk for your RV feels like a quest sometimes, doesn’t it? Let me walk you through the maze with a bit of insight into the types of caulk I’ve encountered on my adventures. Whether you’re dealing with leaks or just doing some preventive maintenance, knowing your caulks can make all the difference.

Silicone Caulk: A Sticky Situation
Ah, silicone caulk, the go-to for so many home DIY projects. It’s fantastic for areas like the shower or kitchen inside your RV, thanks to its anti-mildew properties and resilience against extreme weather and UV rays. But let me tell you, once it’s on, it’s a beast to get off. Re-caulking becomes a Herculean task, so I tend to steer clear of it for general RV use.

Acrylic Caulk: Easy on the Wallet
Acrylic caulk and I have a love-hate relationship. It’s super budget-friendly and a dream when you need to match your RV’s paint job. But it’s not the most flexible option. After experiencing firsthand how it can crack under the stress of temperature fluctuations, I’ve had to bid it farewell for most outdoor applications.

Vinyl Caulk: The Middle Ground
Vinyl caulk reminds me a lot of its acrylic cousin — affordable and paint-friendly. It has a bit more tear resistance, which is a plus. However, like a delicate pastry in changing weather, it can crack when temperatures swing wildly. It’s a decent choice for less exposed areas but might not be the hero we’re looking for.

Fireproof Caulk: Safety First (Or Is It?)
The idea of fireproof caulk is intriguing, especially in an RV where space is tight and the risk is real. It seems like a no-brainer for enhancing safety, but unless the rest of your setup is similarly fire-resistant, it might not be the game-changer you’d expect. Still, it’s worth considering for peace of mind.

Synthetic Rubber Caulks: Flexibility Champions
Now we’re talking! Synthetic rubber caulks have been a revelation for me. Their flexibility and adhesive prowess are top-notch, perfect for those moving joints. Just watch out for the shrinkage post-application and their flammability before they cure. Quick-curing versions have become my new best friends.

Modified Silicone Polymer Caulks: The Future is Here
If there’s a caulk that feels like it’s been engineered by wizards, it’s the modified silicone polymer variety. Yes, your wallet might feel the pinch, but these hybrids are a leak-plugging dream. Waterproof from the get-go, durable, flexible, and no shrinking — it’s like hitting the caulk jackpot.

Why I Swear by RV Caulk: A Game-Changer for RV Owners

The Leak Stopper
Let’s dive right in – the top reason I’m always on top of my caulking game? It keeps my RV dry as a bone. I’ve been through my share of leaky situations, and nothing ruins a cozy interior faster than water sneaking in. Investing in quality RV caulk means I’m not spending my weekends fixing water damage or, worse, spending my money on avoidable repairs.

Mold’s Worst Nightmare
And then there’s mold – that unwelcome guest you didn’t know you were hosting until it’s too late. A tiny leak might not sound like much, but it can turn your RV walls into a mold party hub without you seeing a single sign… until you start sneezing, that is. That’s why I check my caulking religiously; it’s not just maintenance, it’s peace of mind.

The Bug and Dust Barrier
You know what else loves a little gap in your RV? Bugs and dust. There’s nothing like settling down for the night only to find you’re sharing your space with an ant parade or a dust bunny colony. Sealing up with RV caulk keeps those uninvited guests where they belong – outside. It’s like putting up a “No Vacancy” sign for pests and grime.

The Secret to Efficient Heating and Cooling
Ever tried heating your home with the door wide open? That’s what it feels like when your RV isn’t properly sealed. Those gaps might be small, but they’re mighty when it comes to letting out your cozy warmth or that refreshing AC chill. A tight seal with good caulk has saved me a bundle on energy costs, making my RV the perfect temperature oasis without breaking the bank.

Boosting Your RV’s Curb Appeal
Lastly, let’s talk about first impressions. Swapping out old, cracked caulk for a fresh bead not only spruces up your RV’s looks; it’s like a facelift for your home-on-wheels. When it comes time to sell, that attention to detail can really pay off. Buyers see a well-maintained RV and think, “This is the one.” It’s not just caulk; it’s adding value with every squeeze of the caulk gun.

Sealing the Deal
I’ve learned that a little maintenance goes a long way, especially with something as crucial as caulking. It’s about protecting your investment, your health, and even your wallet. And if you ask me, the peace of mind that comes from knowing my RV is sealed tight against the elements and other intruders? Well, that’s just priceless. So, grab that caulk and give your RV the love it deserves – your future self will thank you.

Wrapping Up My RV Caulk Chronicles

Navigating the vast ocean of RV caulks out there has been quite the journey, filled with lessons, surprises, and a fair share of DIY. Given the plethora of options, it’s no small feat to pinpoint the perfect sealant for your beloved home-on-wheels, especially if you’re just dipping your toes into the RV lifestyle.

First off, let’s talk about matching the caulk to the task. Take my trailer’s EPDM rubber roof, for instance. After a bit of research and some trial and error, I landed on the Dicor Self-Leveling Lap Sealant. It’s a godsend for RV roofs like mine, spreading out smoothly, sticking like a dream, and standing the test of time like a champ.

Now, for those tricky vertical seams that seem to move and groan with every mile? I swear by Big Stretch by Sashco. This stuff is the superhero of RV caulks, stretching up to an incredible 500% of its original size without batting an eye. It’s perfect for keeping everything sealed tight, no matter how rough the road or diverse the climate.

And let’s not forget about those just-in-case moments. I always have a tube of Sashco Clear Lexel Adhesive Caulk in my emergency repair kit. It’s the Swiss Army knife of caulks – versatile, UV resistant, and capable of stretching up to 400%. Plus, it seals on contact, even in the middle of a downpour, making it my go-to for unexpected leaks.

Whether you’re a seasoned RVer or just starting out, finding the right caulk might seem daunting. But with a bit of knowledge about what you’re sealing and where, plus some firsthand insights from fellow RV enthusiasts (like yours truly), you’re well on your way to making an informed choice. The right caulk not only protects your RV from the elements but also ensures it remains your cozy, adventure-ready haven for years to come.

So there you have it – my two cents on navigating the world of RV caulks. With the right information and a bit of patience, you’re sure to find the perfect match for your motorhome, keeping your travels smooth and your RV in prime condition. Happy caulking!

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