Home > Roofing > Best Roof Sealants for Leaks (2023 Cost and Reviews)

Best Roof Sealants for Leaks (2023 Cost and Reviews)

Updated Jan 12, 2023

Updated Jan 12, 2023

Home > Roofing > Best Roof Sealants for Leaks (2023 Cost and Reviews)

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The right roof sealant can not only provide a ready solution for roof repair but can provide long-term protection from more extreme weather conditions, including rain and long-term UV exposure. Roof sealants are used for plenty of reasons, including repairs, and helping to get your roof into alignment with Energy Star guidelines. Paying for a professional roof sealant application can be a good way to protect your roof for a couple more decades at the end of its warranty while doing a DIY fix with many of the products we list here can help with a variety of smaller roofing repairs. Here, you’ll learn more about the following:

  • The best roof sealant options for a range of roofing repairs
  • The benefits of different types of roof sealants
  • Why applying a sealant to your roof surfaces may be a good idea

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Roofer applying roofing sealant

Top 5 Best Roof Sealants

We’ve listed our top roof sealants, along with their relative strengths and weaknesses for your consideration. Be sure to take your roofing type and repair needs into account when making your decision between the products here.

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  • Free estimates based on your roof, no phone call required
  • Typically costs between $1–$25 per square foot
  • Get your quote in 30 seconds

LR Waterproof Sealant: Best Overall

Liquid Rubber’s Waterproof Sealant gets our vote for the best overall option. It is one of the most versatile options available and can adhere to any non-oil-based roof surface. This makes it an ideal choice for a wide range of applications, including residential, commercial, and marine uses.

This particular sealant is water-based and easy to apply, making it ideal for most DIYers. As an added bonus, this product is safe for use anywhere. The manufacturer guarantees the following:

  • Safe for families with pets and children
  • Safe for indoor and outdoor use
  • No VOCs
  • Non-flammable

Price: $64.95 per gallon on Amazon

One gallon of this product is rated to cover up to 30 square feet on most roof slopes, with 15 square feet of coverage for most flat surfaces.

Pros & Cons

Pros

  • UV and water resistant
  • Widely applicable across different roof types

Cons

  • Requires layering for full protection
  • Tough to apply in tight spaces

Rubberseal Liquid Rubber Waterproofing and Protective Coating: Best for Low-Pitch Roofs and Protecting Against Standing Water

Rubberseal’s Liquid Rubber coating is ideal for most flat roof applications. It provides a far thicker and heartier consistency, leading to thicker layering and superior water protection. Flat roofs are susceptible to damage from standing water, which Rubberseal’s product protects against. As an added bonus, this is available in multiple colors, including white, light gray, dark gray, and matte black.

If you’re looking for a flat white roof coating to provide extra UV protection, this may be a worthwhile consideration, despite the elevated price.

Price: $82.49 per gallon ($99.99 per gallon for extra strength protection)

One gallon is rated for 60 square feet on flat roofs.

Pros & Cons

Pros

  • Thicker consistency makes for great protection against standing water
  • Color variety widens its number of potential applications
  • Works as an RV roof coating

Cons

  • Difficult application process relative to other rubberized roof sealants

Gorilla Waterproof Patch and Seal Tape: Best for Small Repairs

If yours is a small leak and you’re looking for a quick fix, then Gorilla Waterproof Patch and Seal Tape may be the best choice for you. The four-inch wide strips you’re able to work with can adhere to almost any roofing surface. Unlike the liquid rubber sealants already listed, this tape can be applied in wet conditions and will stick to roofing surfaces despite moisture. We recommend thoroughly drying any workspace prior to any repair regardless.

Price: $12.97 for a single 4” x 10’ roll

Pros & Cons

Pros

  • Available in white and black
  • Easy application for tight spaces and small repairs
  • Can work for small marine and RV applications

Cons

  • Does not work well for larger leaks

Dicor Self-Leveling Lap Sealant: Best Option for RV Roofs

Dicor’s Self-Leveling Lap Sealant is one of the leading products sold in RV supply stores today because of its quality and versatility. This urethane sealant provides excellent coverage and repairs for EPDM and TPO roofing, as well as wood, aluminum, concrete, and more. This caulk is ideal for high-tension surfaces that are consistently exposed to the elements and is a relatively cost-effective solution for smaller repairs.

 Price: $60.65 for 4 10.3-ounce tubes on Amazon

Pros & Cons

Pros

  • UV-stabilized to prevent deterioration
  • Available in multiple colors
  • Applicable to numerous roofing types

Cons

  • Only viable for small repairs

FlexSeal Liquid Rubber in a Can: Best for Quick Repairs

FlexSeal is one of the most recognizable brands of roof sealant today and is available at all major hardware stores and retailers. Its easy application makes it a favorite among DIYers. Whether you’re repairing a leaky roof, gutter system, or any other exterior application, this is the best quick fix on the market.

Price: $34.98 for a 32-ounce can

Pros & Cons

Pros

  • UV-resistant
  • Available in clear, white, gray, and black
  • Easily resealed cans make it easy to store for future use

Cons

  • Degrades quicker than other options in heavily-exposed areas
  • Not recommended for use on vinyl membrane roofing

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  • Free estimates based on your roof, no phone call required
  • Typically costs between $1–$25 per square foot
  • Get your quote in 30 seconds
Liquid rubber sealant is the best overall sealant type, but DIY application can be difficult.
Bitumen primer for a flat roof sealing

How to Choose the Best Roof Sealant Buying Guide

If you’re looking into roof sealants for a DIY leak repair, you’ll want to consider the following aspects of each product you encounter before buying. Generally speaking, roof sealants can be divided into two categories: solvent-based and water-based.

Solvent-based sealants will have longer lifespans but will be tougher to apply to almost any roof. Thicker consistency and quicker adherence to most surfaces will mean that you have to work fast with these materials. In addition, many solvent-based sealants will give off toxic fumes, which may necessitate wearing a respirator of some form.

Water-based sealants are thinner in consistency and are easier to apply but will likely require more frequent applications. In most cases, these will degrade in about half the time of solvent-based sealants.

Solar Reflectivity and Water Resistance

Resistance to UV rays is something worth considering with any roofing repair. Your roof will receive a great deal of direct sunlight. Sustained over many years, this can degrade your material of choice. Rubber, acrylic, and silicone sealants all reflect the sun’s rays well and are often offered in different color options. This makes color matching to your current roof fairly easy. Lighter colors tend to provide more UV resistance, which can improve the insulating qualities of your roof.

Rubber, silicone, and polyurethane sealants are considered waterproof rather than water resistant. That said, you’ll have to apply multiple layers of such sealants to create a truly waterproof barrier. Most sealants will come with directions to guide you through the application process, which should aid in creating a watertight barrier.

Material

  • Acrylic: Acrylic sealants offer the most UV protection for most roofs, which makes them a popular option in hotter climates where roofs are exposed to more direct sunlight. They also provide a moderate level of water protection in most roofing applications.
  • Polyurethane: Polyurethane offers a fairly high rating for moisture protection but is not the most UV-stable option for homeowners. This may not be your best choice if you live in an area with a lot of direct sun and little rainfall.
  • Liquid rubber: Most liquid rubber waterproof sealants are thin and water-based, which makes them ideal for almost any DIY project. The ease of application makes them ideal for both small leaks and large-scale roof sealing projects.
  • Tape: Adhesive sealing tape is by far the easiest sealant method to use and apply. These can be easily found on Amazon or at any hardware retailer. They’re most commonly used to seal tight corners but are not meant for large-scale application.
  • Silicone: Silicone sealants provide excellent UV and moisture protection. That said, they are fairly expensive and are somewhat difficult to apply to large areas, which doesn’t make this type of coating ideal for bigger projects.

 Flexibility

If you live in an area that experiences extreme heat and cold, then you should look for highly-rated silicone or rubberized roof coatings. These will be able to expand and contract with temperature changes over time with less degradation in quality.

Longevity

Every sealant type and manufacturer will supply different warranties and recommendations for reapplication, but most products you’ll find on the open market will last between 10 and 20 years.

As with any roofing repair, the quality of the application will play a role in determining exactly how long your sealant will last, as will the number of layers and thickness of the coats you apply. Thicker coats of roof sealant can last 30 years or more in the right conditions.

C5M Rating

The C1 to C5 scale was created by the International Organization for Standardization. This scale is used to denote a given sealant’s resistance to corrosive conditions in its environment once applied. C1 is appropriate for many residential settings. C5 is primarily used in commercial or marine applications or in areas with high moisture content or air pollution.

Key Takeaways

Ultimately, the best way to seal a leaking roof is by replacing the defective metal roof paneling or shingles. New roof panels or components can come with manufacturer or labor warranties, which may cover repair costs in the future. However, in the event that you’re unable to fully replace your roof, we recommend using a quality liquid rubber sealant. These are typically the most cost-effective options for large and small repairs, and provide the best cross-section of protection capabilities.

When shopping around for roof sealants, you should consider the size of your leak or the extent of your damage repairs, budget, and the utility of any given sealant type. Each kind of roof sealant will be differently suited for different environments and repairs. If you’re looking for a full-scale roof coating option that could reduce your energy costs in the long term, then you should review the list of cool roof-approved products.

Frequently Asked Questions

Is Flex Seal good for roof leaks?

Flex Seal spray rubber coating is a good solution for minor leaks and roofing repairs. Under ideal conditions, it can be an extremely long-lasting sealer and is most often compared to sealant tape for quality and durability. This spray rubber coating can have a lifespan of up to 30 years if not consistently exposed to extreme heat and cold, but can still last more than a decade in rough conditions.

What is the difference between roof sealant and roof coating?

They are functionally very similar, and the terms are often used interchangeably. Roof sealant typically refers to materials used in leak repair or to seal small cracks. Full-scale roof coatings are usually applied at the end of an existing roof’s warranty and are primarily used in commercial applications to extend that roof’s lifespan.

How long does roof coating last?

Elastomeric roof coatings have a typical lifespan of 10-20 years. Once your manufacturer warranty expires, or once your coating is no longer effective, you can have new coating applied on top of your old layer.

What is the most common cause of roof leaks?

Water leaks through your roofing occur for a number of reasons, which are typically a combination of your weather patterns over time, and your roof materials aging. These include:

  • Ponding or standing water due to ice dams
  • Improperly sealed roof seams
  • Missing shingles
  • Clogged gutters
  • Cracked flashing

What are VOCs?

VOCs — volatile organic compounds — are found in all adhesive-based sealants. The addition of these to sealants makes them workable until exposed to open air. Once applied, these compounds evaporate from your sealants during the curing process. You should avoid inhaling the accompanying fumes, as they can be highly toxic in high concentrations or poorly-ventilated areas.

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