Best Caulk for Metal Roof Review and Buying Guide

Sealing

Using metal roof is the new trend of constructing buildings. It uses quality roofing that guarantees longer span of the property. When using a metal roof, experts recommend not to use nails. Instead, screws with rubber plugs will do better. The temperature affects the expansion and contraction of the metal. Thus, the nails may come out and holes on the roof become massive. With this, using the best caulk for a metal roof is a smart decision. 

Best Caulk for Metal Roof
Image by Metal Roofing Alliance

What is caulk, and why is it important?

Caulk is a useful tool to cover cracks and gaps in the roof caused by water damage.

In most cases, the best product for metal roof repair is not a product at all. It is the expertise and ability to recognize what is leaking.

Once you locate the leaks, the metal roof leak stops through the correct sealant.

The Best Caulk For Metal Roof

#1. Sashco – Through the Roof Sealant

via Amazon.com

This product is a roof sealant that efficiently stops the roof leak. It bonds to anything to keep the water out. The good thing about this sealant is it delivers watertight seal for a tough roof repair.

It outperforms standard silicon sealant and asphalt 20 times longer. You can apply it on wet surfaces and even when the rain pours. The best thing is that it does not freeze. Instead, it remains elastic.

This sealant has co-polymer rubber that creates invisible seals and adheres to the roof when applied on rainstorms. But I recommend applying it on dry surfaces for the best results. It can stick to concrete, wood, asphalt, plastic, metal, and more.

Pros

  • Seals fast
  • Sticks to standing water
  • More durable than asphalt
  • Remains elastic
  • Easy blend
  • Freeze stability
  • Paintable

Cons

  • Won’t adhere to tiles

#2. Polyurethane Sealant

via Amazon.com

This is an excellent product you can apply to the roof by using a caulking gun. The good thing about this product is it remains supple, but bonds strong to different surfaces like cement, wood, and brick. 

Because it is pliable, it is a good product to seal windows and even boats. Nothing to worry about applying the sealant on wet surfaces because it would still hold. Even when it’s raining, you can use this to install flashing on your roof. It can still completely cure and does an outstanding job even under moisture.

This is best paired with Oatey Master Flashing 14052. This is a perfect combination for sealing roofs.

Pros

  • Superior adhesion to a wide variety of substrates remains permanently flexible and paintable
  • It guarantees 50-year durability. Works on shingles, gutters, chimneys, skylights, and ducts
  • A good sealant that keeps the moisture away
  • This product provides a permanent solution for your waterproofing needs. You can apply the sealant to fill up or cover cracks and gaps on the roof
  • works in a heavy-duty caulking gun
  • It cures when wet

Cons

  • It’s very stretchy

#3. Aluminum and Metal Silicone Caulk

via Amazon.com

Degraded acrylic caulk can crack and crumble over time, leaving gaps for air and water to seep through. The GE Silicone II is 100% silicone applicable to metals and aluminum materials. Unlike acrylic, silicone is permanently waterproof, while acrylic breaks down in the water. 

It is also flexible, while acrylic becomes less flexible and can even freeze at low temperatures, making it more likely to crack. It is also shrink-proof, while acrylic shrinks as the caulk dries. This shrinking can cause cracks.

Silicon sealant is crack-proof even when exposed to extreme heat and the sun’s UV rays. The silver metallic color looks great, and the squeeze tube is super easy to use. The viscosity is consistent, and the color-matched raw aluminum very well.

Pros

  • It adheres to most aluminum, stainless steel, masonry, brick, concrete, granite, and metal
  • Caulk can decrease the waiting time
  • It helps increase convenience, speed, and efficiency
  • Sun/freeze-proof
  • The permanent flexibility of GE Silicone II keeps it from breaking down so it can protect a surface even as joints expand and contract

Cons

  • The formula is too soft

#4. Advanced Silicon Kitchen and Bath Sealant

via Amazon.com

This comprises of pure silicone and is a waterproof sealant ideal for areas prone to water exposure. This product is permanently flexible than silicon and Class 25 sealants.

For acceptable surface drying, it takes less than 24 hours at room temperature. Complete drying may take 48 to 72 hours.

This GE tube applicator of clear silicone caulk does a magnificent job for a small caulk line. It works great and dries fast.

The caulk can hold up well against frequent contact with water. It sticks well to synthetic stone countertops, vinyl tiles, and even to painted walls, and also water-resistant.

The sealant stays long on the surface and doesn’t discolor metals. It is very easy to use and easy to clean and can withstand extreme expansions and contractions. This product also has a low odor.

Pros

  • It protects the roof from mildew and mold growth
  • Efficient seal that protects water damage
  • Endures extreme shrinking and cracking caused by changes in temperature
  • Can withstand water exposure
  • Remain flexible, but ensures high performance
  • Low odor during the curing process
  • It does not cause discoloration on metal finishes

Cons

  • It is a bit expensive

#5. Loctite Adhesive and Sealant

via Amazon.com

Loctite PL Premium provides superior adhesion to most common construction materials. You can apply it when doing subfloor installations.

Loctite works great for any construction around the house. It is more reliable than metal nails and lasts for several years. Using it holds on tightly to materials, and it also hardens quickly.

It is priced fairly and is well worth the money. It seems to bond well and does not melt Styrofoams. The product has less odor but is very sticky.

I recommend using gloves when applying it. It can be applied directly to dry, wet or frozen lumber.

Pros

  • Loctite can seal fiberglass, drywall, cement-based products, brick, masonry, marble, stone, hardwood flooring, and bonding wood
  • It is three times more adhesive than ordinary construction products.
  • Works well both for exterior and interior use, paintable, easy to cure even in cold weather, and waterproof
  • It prevents water leaks that causes dampness and moisture on your roof or walls
  • It works well on different construction works like sealing fiberglass, metal, masonry, ceramic tile, and wood.

Cons

  • Loctite is very strong and sticky, so you should wear gloves when using it

#6. GE Sealants & Adhesives GE5050 Advanced Silicone 2 Sealant

via Amazon.com

This product contains silicon that is why it protects the roof from possible water damage. It prevents the growth of mildew or mold from the surface. GE Sealants & Adhesives GE5050 cures within 24 hours, thus require at least 30 minutes of tack-free time.

It has outstanding versatility, efficient adhesion and it offers a seal that is long-lasting. This product delivers a flexible seal that withstands UV degradation and freezing temperatures. Many high-end metal finishes, such as nickel, bronze, and chrome, will not discolor. 

Achieve high quality outcomes for a long time. This product guarantees good performance. Since it is a silicon, you can expect that it is also waterproof. It is suitable to apply this sealant in areas exposed to water like a roof, gutter, and the likes. 

Pros

  • Versatile
  • Outstanding performance
  • High-quality
  • Low cost

Cons

  • Only works with metal
  • Non-paintable

#7. Premium Roof Sealant

via Amazon.com

It is easy to apply this product formulated to last longer. By using this roof sealant, we can reduce the cost of roof replacements. The good thing about this product is it delivers the best efficiency at a high value.

The roof sealant produced by Premium PRO works well for various uses. We can use it to seal the roof, gutter, and even roofs of recreational vehicles. 

In RV roof repair, applying this product is an effective solution. Professionals highly recommend this roof sealant. After 30 years in the market, we built this product and both experienced contractors and home handymen have trusted it.

The product works best for winterizing.

Also, it can seal gutters and piercings. The sealant is normally poured onto the roof and then rubbed into place without using a caulk gun.

It requires a minimum of 50 mils of uniform sealant thickness. Do not apply when the air temperature is below 42 degrees F or when the substrate’s temperature is above 120 degrees F.

Pros

  • Fast setting
  • Can resist sagging because of its high-level tensile strength
  • Durable
  • Resistant to water
  • Stays clean

Cons

  • Strong odor
  • More expensive than acrylic coatings

#8. Dicor RV Rubber Roof Sealant

via Amazon.com

The rubber roof sealant works with aluminum, mortar, wood, vinyl, galvanized metal, and concrete. It provides excellent adhesion and improves the capacity to seal continuously and stay flexible.

The product helps develop a seal around the roof’s edges, around air vents, vent pipes, and screw heads. Compatible with every roofing material. This roof sealant does not cause discoloration and oxidation because it is UV stabilized.

Pros

  • Self-lapping
  • Works well with horizontal surfaces only
  • Delivers the job efficiently
  • Great value for the money

Cons

  • Requires thorough cleaning of the spot before applying the sealant
  • Strong odor
  • It is a bit expensive

Buying Guide

Selecting the best caulk for a metal roof is challenging. If you don’t have any idea about such a product, I recommend asking for help from a professional. There are several factors to consider in finding the right product.

Tips to Find the Right Metal Roof Sealant

  1. Before buying a caulk for metal roof, I recommend knowing the construction first. Sometimes, it requires damp-proofing prior to applying the sealant. This way you can properly insulate the roof.
  2. To ensure the caulk or sealant will work better, it is necessary to consider some factors. Think about the flexibility, thermal shock, elongation factor, and waterproofing properties. Choose sealant that has high solar emittance and reflectance for best results.
  3. A good product must have better adhesion, curability, elasticity, movement capability, reactivity, and stress resistance.
  4. Hire a trained person or team to do the job. They know the safety requirements and application parameters necessary for the job.
  5. Use oxime-cure silicon sealant that works well with metal roofs. It offers a better bond and can resist various weather. It prevents discoloration caused by Ultra Violet exposure.
Best Caulk for Metal Roof
Image by Amazon.com

Using caulk or sealant for a metal roof can extend the life span of your house. It would not only stop the prevailing leaks but also provide a permanent solution to the issue. Avoid buying product that can solve the issue in the meantime. It will incur additional costs of repairing the parts where leaks occur.

Metal roofs require sealant that are thicker in consistency. It is more helpful because of its better insulating performance. The consistency is significant, especially if it exposes the roof to excessive heat and cold weather.

Read more: What is The Best Exterior Caulk for Your Sealing Needs

FAQs

Does silicone caulk adhere to metal?

There are many commercial caulks for metal surfaces available. But the silicone caulk is ideal to use. It is easy to apply, can withstand extreme heat and freezing, and flexible. Silicone caulk can seal even smaller gaps. 

Best caulk for metal roof
Image by Amazon.com

How do you stop a metal roof from leaking?

To stop leak from metal roofs, I recommend using oxime-cure silicon that is non-corrosive or polyether sealants.

How do you seal seams on a metal roof?

It is necessary to seal water leaks on metal roofing to prevent further damage. Using waterproof caulk and butyl tape works well to seal seams for long-lasting protection.

What kind of maintenance does a metal roof need?

Metal roofing requires proper maintenance, including regular inspections. Check the distressed fasteners and panels, and other damages caused by environmental elements like snow.

What can I use to seal a leaky roof?

To repair or seal leaks from leaky roofs, you can fill the caulk gun with roofing cement. Reseal the damaged joints by applying extra coat of roof cement. 

Conclusion

It is the owner’s responsibility to maintain the roofs to prevent water leaks that can lead to further damage. To prevent leaks, maintain a clean roof and free of rusty metal shingles, punctures, rust, and fastener back-out. If there is a present leak on your metal roof, the best thing to do is apply caulk or sealant. 

Leaks can still be closed with sealant. Silicone caulk works best for sealing roofs. It is durable and weather resistant that adheres firmly to metal and works well in small gaps. Maintenance and caulking of all roofs are a must, and these efforts could prevent other roof sections from leaking and costing much more.