best seam sealer or tape for old metal roofs

Having dealt with my fair share of leaky old metal roofs, I know the frustration firsthand. That constant drip, the worry of water damage – it’s enough to make anyone want to pull their hair out. But here’s the good news: finding the best seam sealer or tape for old metal roofs can genuinely save you headaches and extend your roof’s life. In this guide, I’ve dug into some of the top products on the market, sharing practical insights to help you make an informed choice and finally achieve a dry, secure roof.

IMAGE	PRODUCT NAME	AMAZON LINK
	EternaBond RoofSeal White 4″ x50′ MicroSealant UV Stable RV…	View on Amazon
	Liquid Rubber Peel and Stick Seam Tape – Fix Leaks,…	View on Amazon
	Xmntdo RV Roof Tape Sealant Waterproof, 8 Inch x 33…	View on Amazon
	Heavy Duty Industrial roof Waterproof Tape, Suitable for…	View on Amazon
	Cofair BST325 Quick Roof Butyl Seam Tape 3″ x 25′	View on Amazon
	GAF Roof Deck Seam Tape (4″ x 67′) – Seals…	View on Amazon
	Kohree RV Sealant Tape, 4 Inch x 50 Foot RV…	View on Amazon
	WELLUCK RV Roof Tape Sealant Roofing Tape, 2 Inch X…	View on Amazon
	Touranize RV Roof Tape with Rubber Roller, 4 Inch x…	View on Amazon
	Peel and Stick Seam Tape, Repair Leaks and Restores Roof…	View on Amazon

EternaBond RoofSeal White 4″ x50′ MicroSealant UV Stable RV…

When you’re serious about sealing an old metal roof, EternaBond often comes up, and for good reason. This tape isn’t just for RVs; its industrial-grade MicroSealant technology forms a truly robust, waterproof, and air-tight barrier. I’ve seen it perform admirably on various surfaces, offering a long-term fix without the need for additional sealants.

Key features that stand out:
* MULTI-USE: Perfect for use on metal buildings, trailer/RV roofs, boats, and more. Bonds to EPDM, TPO, Hypalon, aluminum, galvanized steel, wood, and fiberglass.
* NO ADDITIONAL SEALING REQUIRED: Aluminum backing with advanced MicroSealant creates a waterproof, moisture, and air tight barrier that remains flexible to -57°C (-70°F).
* DURABLE SURFACE: Industry-leading one-step repair system creates a protective coating for abrasion and corrosion resistance.
* EXCELLENT UV RESISTANCE: Features a durable and UV-stable backing that withstands deterioration in fluctuating temperatures and direct sun exposure.
* EASY TO USE: Simple and quick one-step repair; sticky tape with no messy solvents to clean up.

Pros:
* Extremely durable and long-lasting, even in harsh conditions.
* Superior UV stability means it won’t degrade quickly in sunlight.
* Forms a complete, flexible seal without needing extra coatings.
* Versatile for a wide range of materials, including most common metal roof types.

Cons:
* Can be a higher initial investment compared to some other tapes.
Best for: Demanding repairs on commercial metal roofs, RVs, and any application needing a truly industrial-strength, UV-stable, and flexible seal.
Expert Opinion: This is a top-tier choice for heavy-duty, permanent repairs where performance and longevity are paramount.

Liquid Rubber Peel and Stick Seam Tape – Fix Leaks,…

If you’re already familiar with Liquid Rubber coatings or are looking for a foundational layer for a complete waterproof system, this seam tape is an excellent companion. It’s incredibly versatile, bonding to a huge array of materials, making it a reliable first step in sealing leaks on your old metal roof before applying a protective liquid rubber coating.

Key features that stand out:
* USE FOR: RV roofs, metal roofs, flat roofs, trailers, campers, mobile homes, gutters, foundations, ponds, planter boxes, basements, skylights, vents, and shower liners.
* FOR A VARIETY OF MATERIALS: Bonds to EPDM, metal roofs, tiles, shingles, aluminum, wood, fiberglass, brick, and concrete.
* APPLICATION: Clean and dry the surface, install directly over the repair area, and roll or rub to activate bonding.
* EASY TO USE: Peel off the plastic backing, press to adhere, and then coat over with Liquid Rubber Coatings.
* COAT LIQUID RUBBER SEAM TAPE WITH: Liquid Rubber Waterproof Sealant, Liquid Rubber Color Sealant, Liquid Rubber RV Roof Coating, Liquid Rubber Foundation Sealant, Liquid Rubber MetalSafe Sealant.

Pros:
* Highly versatile, bonding to almost any common roofing material.
* Provides an immediate seal that can then be reinforced with compatible coatings.
* Easy peel-and-stick application for DIYers.
* Ideal for creating a multi-layer waterproofing system.

Cons:
* Designed to be coated over, so it’s not a standalone UV-stable finish.
Best for: Users planning to apply a Liquid Rubber coating system, or for preliminary leak fixes on various surfaces before a final topcoat.
Expert Opinion: An essential component for a comprehensive Liquid Rubber waterproofing strategy, offering excellent base adhesion.

Xmntdo RV Roof Tape Sealant Waterproof, 8 Inch x 33…

When you’ve got a larger crack or a wider seam on an old metal roof, the Xmntdo 8-inch wide tape is a lifesaver. Its super strong butyl adhesive means it sticks firm and stays put, even with roof movement and weather changes. I appreciate how it effortlessly conforms to irregular surfaces, providing that peace of mind that your repair is truly comprehensive.

Key features that stand out:
* Super Strong Adhesion Waterproof Seam Tape: Uses high-quality butyl adhesive with strong adhesion, resisting vibration, wind pressure, and temperature changes.
* Professional-Grade All-Weather Waterproof Repair Tape: Engineered for RV roofs and seams, forming an impermeable barrier to stop leaks permanently. UV-resistant and weatherproof.
* Waterproof Tape Easy to Use: Clean and dry surface, peel off backing, press gently. Flexible design fits curves and irregular surfaces. Can be coated over.
* Widely Applicable Scenarios: Great seal for RVs, RV roofs, trailers, campers, motorhomes, metal roofs, flat roofs, steel roofing color plates, gutters, foundations, ponds, planters, basements, skylights, and automotive/construction.
* Bonds All Surfaces: Securely adheres to metal, plastic, wood, EPDM, PVC, and TPO.

Pros:
* Extra-wide 8-inch coverage is perfect for larger repairs and seams.
* Exceptional adhesion and flexibility for various surfaces and conditions.
* Professional-grade durability ensures long-lasting leak protection.
* UV-resistant and weatherproof, suitable for extreme conditions.

Cons:
* The wide size can be a bit challenging to manage for very small or intricate areas.
Best for: Addressing wide cracks, larger seams, and areas on old metal roofs that require significant, robust coverage.
Expert Opinion: The generous width and strong adhesion make this tape a go-to for serious repairs where broad, durable sealing is needed.

Heavy Duty Industrial roof Waterproof Tape, Suitable for…

This industrial-grade tape brings more than just waterproofing to the table; it’s a multi-tasker with thermal insulation properties. For old metal roofs that might also suffer from heat transfer issues, the PE anti-sun film is a welcome addition. Its high temperature resistance and strong aging resistance mean it’s built to endure, which is exactly what you need for an exposed metal surface.

Key features that stand out:
* Strong adhesion and good tensile strength: Ensures it sticks firmly and provides a reliable fix.
* Thermal insulation: Equipped with a PE anti-sun film, regulating temperature and preventing heat loss.
* High temperature resistance and long service life: Withstands extreme heat without losing adhesive properties, ensuring durability.
* Waterproof and not easy to age: Features a nano waterproof coating to prevent water penetration and resist aging.
* Great adhesion and aging resistance: Bonds effectively to different surfaces, including metal and color steel, maintaining performance long-term.

Pros:
* Combines excellent waterproofing with thermal insulation.
* Designed to withstand high temperatures and resist aging, extending its lifespan.
* Strong adhesion on various surfaces, including metal.
* Durable nano waterproof coating for superior protection.

Cons:
* The industrial focus might make it seem like overkill for minor, non-thermal-related leaks.
Best for: Old metal roofs in industrial settings, or where both waterproofing and some degree of thermal regulation are desired.
Expert Opinion: A robust option for challenging environments where thermal resilience and long-term durability are critical alongside waterproofing.

Cofair BST325 Quick Roof Butyl Seam Tape 3″ x 25′

Sometimes, you’re not just patching a hole but splicing two pieces of roofing material together. That’s where the Cofair Quick Roof Butyl Seam Tape excels. Its double-sided butyl adhesive is specifically designed for creating strong, waterproof seams between EPDM, TPO, Hypalon, modified asphalt, and metal. It’s a specialized tool for a specific job, and it does that job very well.

Key features that stand out:
* EPDM Quick Roof Seam Tape: Designed for quick and effective roof repairs.
* Double-sided butyl adhesive: Provides strong, reliable bonding on both sides.
* Designed to splice two pieces of rubber together into a waterproof seam: Ideal for joining roofing membranes.
* Use with EPDM, TPO, Hypalon, modified asphalt, metal roofs, gutters and flashings: Wide material compatibility.
* Size: 3″ x 25′: Convenient size for various projects.

Pros:
* Excellent for splicing and joining different roofing membranes securely.
* Strong double-sided butyl adhesive creates a truly waterproof bond.
* Compatible with a range of common roofing materials, including metal.
* Reliable for flashings and gutter repairs.

Cons:
* Its primary function is splicing, so it may not be the most straightforward for simple surface crack repairs.
Best for: Professionals or DIYers needing to splice and join existing roofing membranes or materials on an old metal roof to create a new, waterproof seam.
Expert Opinion: This is a niche, yet highly effective, product for making seamless, durable connections between roofing materials, crucial for complex repairs.

GAF Roof Deck Seam Tape (4″ x 67′) – Seals…

While technically designed for roof deck joints under shingles, this GAF tape deserves a mention for its incredible fastener-sealing capabilities and robust construction. For old metal roofs that are getting a complete overhaul or re-decking, this tape provides an enhanced layer of defense against water intrusion at the structural level. Its fiberglass-reinforced SBS-modified asphalt construction ensures serious durability.

Key features that stand out:
* Enhanced Protection: Provides an additional self-adhering layer of defense against water intrusion at deck joints, especially during severe weather.
* Fastener Sealing: Self-seals around fasteners, offering added protection.
* Durable Construction: Made from fiberglass-reinforced SBS-modified asphalt, ensuring long-lasting strength and reliability.
* Improved Traction: Textured outer surface enhances traction, making installation safer and easier.
* Easy Handling: Features a silicone-treated release liner for smooth and hassle-free application.
* Code Compliant & Approved: Meets or exceeds ASTM D1970 requirements and various building codes.

Pros:
* Exceptional at sealing around fasteners, a common source of leaks on older roofs.
* Fiberglass-reinforced for superior strength and durability.
* Code-compliant, offering peace of mind for major repair projects.
* Improved traction on its surface aids safer installation.

Cons:
* Primarily intended for use under other roofing materials, not as an exposed top-layer seam sealer.
Best for: Major roof overhaul projects where sealing roof deck joints and fasteners beneath the primary roofing material is crucial.
Expert Opinion: A foundational product for maximizing the long-term waterproof integrity of a roof, especially for those concerned about fastener leaks.

Kohree RV Sealant Tape, 4 Inch x 50 Foot RV…

The Kohree RV Sealant Tape is a favorite among RV owners, but don’t let the “RV” in the name fool you – its excellent weatherproofing and UV-resistant qualities make it perfectly suitable for old metal roofs as well. It’s super sticky and flexible, which means it can conform to those trickier curves and corners that often plague older, uneven metal surfaces.

Key features that stand out:
* WEATHERPROOF & UV-RESISTANT SEALANT TAPE: Water-tight strong adhesive tape resists UV, moisture, vapor, corrosive chemicals, and other leakages.
* PROFESSIONAL RV & MOBILE REPAIR: Specially designed for RV repair, compatible with Metal, EPDM, PVC, Hypalon, and TPO.
* EASY INSTALLATION: Super sticky and flexible features allow installation on most flat, curve, or corner surfaces.
* LONG LIFESPAN: Adopted premium Butyl, ensuring a self-priming seal and long-lasting usage.
* WIDE APPLICATIONS: Widely applied in sealing RVs, RV Roof, Metals, Motorhomes, Trailers, Fifth Wheels, Airstreams, Vans, Buses, and more!

Pros:
* Excellent weather and UV resistance for outdoor exposure.
* Highly flexible, making it easy to apply on irregular or curved metal surfaces.
* Strong butyl adhesion creates a reliable, long-lasting seal.
* Versatile for various materials beyond just RVs, including general metal roofing.

Cons:
* While suitable for metal, its branding might suggest a primary focus on RV applications.
Best for: Repairing leaks on RVs, mobile homes, and old metal roofs where flexibility to conform to varied surfaces is important.
Expert Opinion: A dependable and flexible butyl tape that performs well on metal, offering solid weather and UV resistance for lasting repairs.

WELLUCK RV Roof Tape Sealant Roofing Tape, 2 Inch X…

Sometimes, a narrower tape is exactly what you need for precise crack repairs, and the WELLUCK 2-inch tape fits the bill. What I really like about this one is its “Natural Pure White Quality.” On an old metal roof that might be white or light-colored, this tape blends in seamlessly and also helps reflect sunlight, which is a neat bonus. It’s professional-grade for RVs but easily translates to other metal roofing needs.

Key features that stand out:
* 【Professional RV/Mobile Repair Tape】: Industrial-grade RV Roof tape, specifically designed for the RV’er, forms a tough and durable repair.
* 【UV-Resistant and Weatherproof】: Creates a waterproof airtight barrier, remains flexible to -40ºF, making it impossible to thermally shock the seam.
* 【Natural Pure White Quality】: No binders or fillers, closer to RV roof color, effective in reflecting sunlight, and avoids messy asphalt look.
* 【Easy to Install】: Clean area, cut to size, peel off backing, lay it down, and press. Flexible and sticky enough to cut and fold.
* 【Works on All Roofing Materials】: High coefficient of expansion allows expansion/contraction to adjust to extreme temperatures. Applies to RVs, RV Roof, Metals, Motorhomes, Trailers, and more!

Pros:
* Pure white color offers aesthetic benefits and sun reflection.
* Excellent UV and weather resistance, maintaining flexibility in extreme temperatures.
* Easy, straightforward installation process.
* Works reliably on a wide range of roofing materials, including metal.

Cons:
* The 2-inch width might require multiple strips for wider cracks or seams.
Best for: Smaller cracks, precise seam repairs, or old metal roofs where a clean, white, UV-reflective finish is preferred.
Expert Opinion: A great option for discreet, durable repairs, especially where matching a white roof or reflecting heat is a consideration.

Touranize RV Roof Tape with Rubber Roller, 4 Inch x…

This Touranize tape stands out immediately because it comes with an essential tool: a rubber roller. Proper adhesion is critical for any tape, and a roller ensures you get that firm, lasting bond. Like many good RV tapes, it’s highly durable, weatherproof, and UV-resistant, making it a strong contender for old metal roof repairs, especially if you want a complete, ready-to-use kit.

Key features that stand out:
* Professional RV Repair: Specifically designed for RV and camper repair, effectively stopping leaks and binding cracks, tears, and seams.
* Weatherproof & UV Resistant: Made of premium butyl material and upgraded Fluorocarbon film, resisting various weather conditions and remaining flexible from -40°F to 140°F.
* Easy to Use & With Roller: Simple and quick repair without additional adhesive. The ATTACHED ROLLER makes installation easier.
* Wide Applications: Widely applied in sealing RVs, RV Roof, Metals, Rubber, Wood, Vinyl, Glass, Motorhomes, Trailers, Fifth Wheels, Vans, Buses, and more.
* Long Service Life: Tested to be used for more than 5 years, achieving long-term to permanent repair.

Pros:
* Includes a rubber roller, ensuring optimal adhesion and a professional finish.
* Highly durable with excellent weather and UV resistance.
* Maintains flexibility across a broad temperature range.
* Versatile for many materials, including metal, and designed for long-term use.

Cons:
* The primary “RV” branding might slightly deter those looking solely for industrial metal roof solutions.
Best for: DIY enthusiasts tackling old metal roof repairs who appreciate a complete kit, including the crucial application roller, for guaranteed adhesion.
Expert Opinion: The inclusion of a roller is a significant advantage, helping ensure every application achieves maximum contact and durability.

Peel and Stick Seam Tape, Repair Leaks and Restores Roof…

Sometimes you just need a straightforward, effective solution, and this generic “Peel and Stick Seam Tape” delivers. It’s user-friendly, suitable for a vast array of materials (including metal roofs), and boasts strong adhesive properties. For general household and roof repairs, it’s a solid choice that gets the job done without fuss, and the wide range of use ensures versatility.

Key features that stand out:
* Easy to use: 4 inches wide and 50 feet long, with strong adhesive on the back. Cut to length, tear off backing, press to bond, and apply sealant/coatings if desired.
* Wide range of use: Widely used for metal roofs, RV roofs, campers, flat roofs, gutters, skylights, vents, shower liners, ponds, foundations, basements, etc.
* Application: Remove impurities and keep the substrate surface dry. Activate bonding by pressing or rolling.
* Suitable for a variety of materials: Bonds to metal roofs, wood, shingles, EPDM, fiberglass, tiles, and concrete, maintaining excellent performance even in harsh environments.
* Customer Support: Strictly manufactured and backed by customer support.

Pros:
* Very easy to apply, making it ideal for DIY repairs.
* Highly versatile, suitable for a wide range of surfaces and leak types on metal roofs.
* Strong adhesive ensures excellent bonding and sealing performance.
* Cost-effective solution for many common leak issues.

Cons:
* Generic branding might mean less specific long-term testing data readily available compared to brand-name products.
Best for: General purpose leak repairs on old metal roofs, quick fixes around the house, and for those who value simplicity and versatility.
Expert Opinion: A reliable, no-frills option that provides effective sealing for a multitude of common roof leaks.

Helpful Comparison Short Insights

When choosing the best seam sealer or tape for old metal roofs, consider a few key aspects. For heavy-duty, long-term, and UV-exposed repairs, EternaBond and Xmntdo (especially for wider seams) are hard to beat, offering industrial-grade resilience. If you’re tackling a major project or an area that gets a lot of sun, their robust construction and UV stability are a huge plus.

For those planning to use a liquid coating system, the Liquid Rubber Peel and Stick Seam Tape is an excellent preparatory layer, designed to work in conjunction with their other products. Similarly, the GAF Roof Deck Seam Tape is specifically for underlayment and fastener sealing, not exposed repairs, but crucial for comprehensive leak protection during a re-roof.

Many of the RV-branded tapes, like Kohree, WELLUCK, and Touranize, offer fantastic flexibility and weather resistance, making them great for the movement and temperature fluctuations common with old metal roofs. The Touranize tape even includes a roller, which is a smart addition for ensuring proper application pressure. If aesthetics matter, WELLUCK’s natural pure white tape is a good choice for blending in.

Finally, for unique needs, the Cofair BST325 is designed specifically for splicing membranes, while the Heavy Duty Industrial tape adds thermal insulation, a unique benefit for specific environments. Overall, surface preparation is key for all of these, regardless of which product you choose.

Final Verdict: Finding Your Roof’s Perfect Patch

Navigating the world of sealers and tapes for old metal roofs can feel overwhelming, but ultimately, the best seam sealer or tape for old metal roofs is the one that best matches your specific repair needs, budget, and desired longevity.

If you’re looking for an uncompromising, permanent solution that withstands the harshest conditions, the EternaBond RoofSeal is my top recommendation. Its proven durability and UV stability make it worth the investment for critical repairs. For larger areas or wide seams, the Xmntdo 8-inch tape offers impressive coverage and adhesion.

For those on a tighter budget or doing more general patching, products like the Kohree RV Sealant Tape or the generic Peel and Stick Seam Tape provide reliable, easy-to-use options. If you’re pairing with a liquid coating, the Liquid Rubber Peel and Stick is a no-brainer. And don’t underestimate the value of a roller – the Touranize RV Roof Tape with its included roller helps ensure you get the absolute best adhesion possible, which is vital for any long-lasting repair.

No matter your choice, remember that proper surface cleaning and preparation are absolutely non-negotiable for these products to perform their best. A little prep work goes a long way in making sure your old metal roof stays leak-free for years to come.

Comprehensive FAQ Section

1. What’s the difference between seam sealer tape and liquid sealant for old metal roofs?
Seam sealer tape is a pre-formed, self-adhesive strip that provides an immediate physical barrier over cracks or seams. Liquid sealants are applied as a coating that cures into a waterproof membrane. Tapes are generally quicker for targeted repairs, while liquid sealants are often used for larger areas or as a topcoat over tapes for enhanced protection and a seamless finish. Both can be effective for the best seam sealer or tape for old metal roofs.

2. How do I prepare an old metal roof surface for sealing?
Preparation is crucial! First, thoroughly clean the area by removing any loose debris, rust, dirt, oil, or old flaking paint. A stiff brush or power washer (used carefully) can help. Degrease the surface with an appropriate solvent (like mineral spirits or denatured alcohol) and ensure it’s completely dry before applying any sealer or tape. Roughing up very smooth metal surfaces slightly with sandpaper can also improve adhesion.

3. How long do these tapes or sealers last on old metal roofs?
The lifespan varies significantly by product quality, proper application, and environmental factors. High-quality butyl and EPDM tapes, especially those with UV-stable backings like EternaBond, can last 10-20 years or more. More generic tapes might last 3-7 years. Liquid sealants often offer similar long lifespans, especially if they are reinforced. Always check the manufacturer’s warranty and specifications for specific durability claims.

4. Can I paint over seam sealer tape?
Many seam sealer tapes can be painted over, especially those designed to be compatible with acrylic or elastomeric coatings. Look for tapes that explicitly state they are paintable or can be coated over. Tapes like Liquid Rubber’s are designed to be coated, and some white butyl tapes (like WELLUCK’s) can blend in well or accept a topcoat. Always test a small, inconspicuous area first to ensure compatibility and adhesion of the paint.

5. What temperature is best for applying seam sealer or tape?
Most manufacturers recommend applying seam sealer tape when temperatures are moderate, typically between 40°F (5°C) and 90°F (32°C). Extremely cold temperatures can make the adhesive less tacky and flexible, while very hot temperatures can make the tape difficult to handle and potentially affect initial bonding. Always check the specific product’s instructions for optimal application temperatures.

6. Is professional installation required for the best seam sealer or tape for old metal roofs?
For most peel-and-stick tapes, professional installation isn’t strictly required, making them excellent DIY options. However, for extensive damage, complex roof geometry, or if you’re uncomfortable working at heights, hiring a professional roofer is always a wise decision. Proper surface preparation and firm application (often with a roller) are key to ensuring the chosen best seam sealer or tape for old metal roofs performs as intended.

7. What kind of seam sealer or tape should I choose if my old metal roof has a lot of movement?
If your old metal roof experiences significant expansion and contraction due to temperature changes or structural movement, you need a highly flexible seam sealer or tape. Butyl-based tapes (like EternaBond, Xmntdo, Kohree, or Touranize) are excellent choices as they remain pliable across a wide temperature range and can flex with the roof without cracking or losing adhesion. Look for products that explicitly mention flexibility or temperature range resistance in their features.