Best RV Roof Caulks: When To Use Self Leveling Lap Sealants

What Kind Of Caulking Do You Use On An RV Roof?

Preventing a leaky RV roof is far easier than dealing with water damage later. With fast-moving water damage being a serious threat, choosing the right RV caulk is essential to keep your roof watertight.

For RV roofs, self-leveling lap sealant is the top choice. Unlike non-sag caulks, self-leveling sealant spreads evenly over seams, vents, and skylights, creating a smooth, watertight surface that prevents gaps and ensures reliable protection.

Related Product: We level our RV with the innovative Andersen RV Leveling Set (click to view on Amazon)

Why self-leveling caulk?
It forms a flat, continuous seal that water easily runs off. While non-sag caulk can leave gaps when applied to uneven surfaces, self-leveling caulk spreads out to fully cover seams and screws, offering superior leak prevention.

When to use non-sag caulk:

• Around thick edges like a TV antenna, where non-sag caulk provides a secure seal before applying self-leveling caulk.
• On curved or vertical surfaces where self-leveling caulk won’t stay in place.

In this guide, I’ll review the best RV self-leveling lap sealants available today, including those favored by manufacturers and full-time RVers. Don’t miss the “What to Look For” and “FAQ” sections for tips on choosing the right caulk for your camper.

See Also: What Are RV Roofs Made Of? A Quick Guide To Camper Roofs

Best RV Caulks For RV Roofs

1. Dicor RV Self-Leveling Lap Sealant

Check Price at Amazon

Dicor is a top-rated RV caulk brand trusted by manufacturers and RV enthusiasts alike.

This polyurethane-based sealant offers excellent waterproofing and flexibility, making it ideal for RV roofs. It bonds effectively with various materials, including rubber, aluminum, fiberglass, and vinyl. While there’s a note about limited compatibility with some TPO roofs, it has performed well in personal use on TPO surfaces.

The sealant creates a tight, flexible, and UV-stabilized waterproof seal that resists cracking or brittleness, even after years of use.

With a quick cure time, it’s rain-ready in just 4 hours and 80% cured within 48 hours. Available in multiple colors, it’s perfect for matching your RV roof while keeping it cool with its reflective white option.

For best results, apply a generous 1/4-inch bead, especially when sealing roof vents or screws. A single tube covers most standard RV roof jobs, making Dicor a reliable and cost-effective choice.

See Also: Best RV Roof Coatings That Seal & Protect (All Camper Roofs)

2. Ziollo RV Flex Repair Self Leveling Sealant

Check Price at Amazon

The Ziollo RV Flex Repair Sealant is a versatile option with a hybrid polymer base, suitable for most RV roofs, including EPDM rubber, aluminum, and fiberglass.

However, its performance on TPO roofs requires a TPO primer, which can be challenging to source, making it less ideal for those surfaces.

One of its standout features is the ability to bond with existing caulk. While most RV sealants require old caulk to be removed entirely, Ziollo can be applied directly over clean, intact caulking.

This makes it a convenient solution for quick fixes, especially in wet conditions when immediate action is needed to stop leaks.

Despite its convenience for emergency use, it takes longer to fully cure and become waterproof compared to other RV sealants. However, it is paintable within 24 to 48 hours and offers an extended shelf life, making it a reliable product to keep on hand for unforeseen roof repairs.

See Also: 6 Best Exterior RV Caulks For Camper Window, Molding & Trim

3. Alpha Systems RV Self Leveling Lap Sealant

Check Price at Amazon

Alpha Systems RV Self-Leveling Lap Sealant is a top choice for resealing RV roofs, particularly for TPO rubber roofs. It’s also compatible with aluminum, fiberglass, and EPDM rubber roofs, making it versatile for various RV types. This sealant uses a low VOC formula, making it safer for users and the environment.

Unlike some other sealants like Dicor, Alpha Systems require a slightly thicker application because of its limited spreading ability. However, it creates a durable watertight bond and is highly resistant to weather and vibrations from travel.

For a complete resealing, Alpha Systems also offer complementary products like cleaners and tapes designed to work together seamlessly.

The sealant cures to a waterproof state in 4 hours and fully cures in 48 hours. It comes in a standard 10.3 oz caulking tube and is available in white, grey, beige, and almond colors, making it easier to match your RV’s roof.

See Also: 6 Best Diesel Heaters For Campers, RVs & Vans

4. Premier Pro Products RV Roof Sealant Caulk

Check Price at Amazon

Premier Pro Products offers a unique approach to RV roof sealing with its resealable bag packaging instead of the typical caulking tube. This design simplifies the application process, requiring fewer tools, and makes it easy to store for future use.

Each bag contains 25.3 oz of sealant, equivalent to about 2.5 standard caulking tubes. The sealant is universal, adhering to all roof types, including aluminum, fiberglass, TPO, and EPDM rubber. It’s particularly suited for emergencies or quick fixes due to its fast-drying formula that becomes waterproof almost instantly under ideal conditions.

While it applies thinner than traditional self-leveling caulks, its durability and waterproofing capabilities remain reliable. It can also be used over existing caulk, making it versatile for quick repairs or resealing cracked seams.

See Also: Best Portable Power Station/Solar Generator For Camping

What To Look For In RV Roof Caulk

Roof Material Compatibility

RV roofs are typically made of TPO rubber, EPDM rubber, aluminum, or fiberglass. For aluminum or fiberglass roofs, most self-leveling lap sealants in this review will work well. Just be sure to prep the surface properly by roughing it up with a brush and cleaning it with denatured or isopropyl alcohol.

Rubber roofs are the most common and will either be TPO or EPDM. Knowing which type your RV has is important since compatibility varies. Most sealants here work on both types, except the Ziollo RV Flex Repair Sealant, which requires a primer for TPO roofs.

Cure Time

Cure time can be a concern if you’re working outdoors in unpredictable weather. While most self-leveling RV caulks become waterproof within a few hours, full curing can take days or even weeks.

For emergencies, the Premier Pro Products RV Roof Sealant Caulk or Ziollo RV Flex Repair Self Leveling Sealant are great options as they can seal leaks quickly, even in wet conditions.

When resealing your RV roof, plan for at least a few calm, dry days to avoid issues with uncured caulk. All the sealants reviewed here offer excellent weather resistance after 48 hours, though some may take longer to fully cure.

Best RV Roof Caulk

Choosing the best RV self-leveling lap sealant depends on your RV’s roof material, the purpose of the sealant, and even the weather conditions during application.

Best For Fixing Leaks As They Happen

For fixing leaks in wet conditions, the Ziollo RV Flex Repair Self Leveling Sealant is one of the few products that works effectively while it’s raining.

Best To Have On Hand To Repair Damaged RV Roof Caulk

The Premier Pro Products RV Roof Sealant Caulk is ideal for quick fixes. Its resealable bag and ability to bond with old caulk make it a great option to keep handy for unexpected repairs.

Best For TPO Rubber RV Roofs

If your RV has a TPO rubber roof, the Alpha Systems RV Self Leveling Lap Sealant is the most reliable choice.

Most Popular Option

The Dicor RV Self-Leveling Lap Sealant is a favorite among RVers and even used by manufacturers in factories. It’s highly versatile, durable, and works on most RV roof materials.

I’ve used it on several TPO roofs with excellent results—it hasn’t cracked, peeled, or failed even after years of use.

For general use, Dicor is my top pick unless you have a TPO roof, in which case Alpha Systems is a better choice. Both are trusted, high-quality options that will help keep your RV roof leak-free.

Frequently Asked Questions About RV Roof Caulks

Why Did the RV Caulk I Used On My RV Roof Start Peeling Off?

RV self-leveling caulk is designed for various roof materials like TPO rubber, EPDM rubber, aluminum, and fiberglass. If your caulk starts peeling or doesn’t bond well, the most common issue is inadequate surface preparation.

Proper cleaning is crucial before applying caulk. Remove old caulk, dirt, and debris, then do a final cleaning with rubbing alcohol to eliminate oils or residues that can prevent adhesion. Skipping these steps often leads to peeling edges or poor bonding.

What Caulk Do RV Manufacturers Use as an RV Roof Sealant?

Most RV manufacturers rely on two leading products:

1. Dicor RV Self-Leveling Lap Sealant: A versatile and widely used choice for various RV roof types.
2. Alpha Systems RV Self-Leveling Lap Sealant: Preferred for TPO rubber roofs because of its superior compatibility.

Can I Use Flex Seal On My RV Roof?

Flex Seal, known for its “rubber in a can” products, is affordable and widely available, but it’s not ideal for RV roofs.

While it can provide temporary watertight protection, it lacks the durability and specific properties of RV-specific caulks designed to handle the stress and weather exposure of camping.

Flex Seal might work in an emergency, but for long-term results, stick to high-quality RV caulks like Dicor or Alpha Systems.

These products are formulated to endure the conditions RV roofs face and offer better leak prevention.

Have any more questions about RV self leveling roof sealant or sealing a camper roof? Leave a comment below.