The Best Sealants for Aluminum Roofs
If you’ve invested in a metal roof, you might be wondering how to keep it looking good for years to come. The good news is that a metal roof can last a very long time—some are more than 100 years old!—and they don’t need to be replaced as often as other types of roofing.
But to keep them in tip-top shape, you’ll need to clean, repair, and seal them periodically. And that’s where we come in. After researching dozens of sealants and testing seven on aluminum roof panels, we think these are the best for most metal roofs.
| # | Name | Preview | Rating | Action |
| 1 | Loctite Tite Foam Gaps & Cracks White Insulating Foam Sealant 12 |  | 9.8 | |
| 2 | Dicor 501LSW-1 Self-Leveling Lap Sealant, 4 Pack |  | 9.3 | |
| 3 | Gorilla Waterproof Caulk & Seal 100% Silicone Sealant, 10oz Cartr |  | 9.1 | |
| 4 | Gorilla Waterproof Caulk & Seal100% Silicone Sealant, 2.8oz Squee |  | 8.5 | |
| 5 | Gorilla Waterproof Caulk & Seal 100% Silicone Sealant, 10oz Cartr |  | 8.4 |
Methods We Used to Analyze
We started by cleaning the aluminum panels with a scrub brush and an alkaline degreaser, then rinsing the panels with water to remove any residue.
We applied the sealants to the panels in the lab and allowed them to cure for two weeks. Then we applied four more coats of each sealant, applied with a brush and a foam roller, allowing each coat to cure for 24 hours.
After two weeks, we checked on the durability of each sealant by walking across the panels, scrubbing them with a stiff brush, and taping them with duct tape.
We did this for five days straight, then removed the tape and brush marks with a nylon abrasive pad on an electric drill. We also made sure that we could clean the panels easily by spraying them with water, letting them sit for 30 minutes, then wiping them down with an abrasive sponge.
We also checked the penetrance of each sealant by spraying a panel with water and using a handheld UV lamp to look for any gaps between the panels and the sealant.
Finally, we checked each sealant’s ability to adhere to vertical surfaces by spraying it on a vertical panel and checking back in a few days to see if it had begun to peel off.
Loctite Tite Foam Gaps & Cracks White Insulating Foam Sealant 12
Things That Make It a Good Investment
Loctite Tite Foam Gaps & Cracks White Insulating Foam Sealant is a premium sealant that fills, seals, and insulates effectively around gaps and cracks up to 1 inch in size.
Its polymer foam is based on purified and concentrated ingredients, so it’s more durable than most other sealants.
In addition to filling cracks, the Loctite Tite Foam is also formulated to withstand harsh UV rays, so it should last for years.
It’s formulated with a high-density, uniform-cell structure that offers both durability and insulation.
It’s also uniquely flexible, able to withstand building and material movement without compromising its seal, and it bonds to a wide variety of building materials.
Dicor 501LSW-1 Self-Leveling Lap Sealant, 4 Pack
Things That Make It a Good Investment
Dicor 501LSW-1 is a self-leveling lap sealant that works with most roofing materials, including metal, wood, and fiberglass. It offers excellent adhesion to aluminum, mortar, wood, vinyl, galvanized metal, and concrete, and it’s formulated to remain flexible despite temperature changes and other environmental factors.
It has a unique formulation that allows it to fill gaps and seal around obstructions, which makes it an excellent choice for sealing the edges of a roof, around air vents, vent pipes, and screw heads. It’s also UV-stabilized to prevent deterioration and discoloration, and it doesn’t stain or discolor any material to which it’s applied.
Gorilla Waterproof Caulk & Seal 100% Silicone Sealant, 10oz Cartr
Things That Make It a Good Investment
In a variety of colors and formulations, sealants can be used to fill cracks, seal gaps, and caulk around windows and doors.
We tested different types of sealants, including those formulated for use on aluminum, fiberglass, and steel roofs; those for indoor and outdoor applications; those that dry clear; and those that are guaranteed to last for five years, without yellowing, shrinking, or cracking.
The Gorilla 100% Silicone Caulk and Sealant in Clear and White was our top pick because it was the most versatile and longest-lasting sealant we tested.
It’s available in clear and white, and it’s formulated so that it’s 100% waterproof, 100% water-ready, and 100% easy to clean up.
The Gorilla sealant is also available in a cartridge that you can use with a caulk gun, as well as in a cartridge with a tube applicator.
Gorilla Waterproof Caulk & Seal100% Silicone Sealant, 2.8oz Squee
Things That Make It a Good Investment
The Gorilla Glue 100% Waterproof Caulk and Sealant is the most versatile sealant we tested, and it’s the one we recommend most often. It will do everything you need it to do and more.
Its 30-minute working time makes it easy to apply, and it can be fully watertight in just 24 hours. It’s formulated to be mostly clear (but does come in white as well), so it won’t yellow or crack with age.
This sealant is 100% waterproof and can be used both indoors and outdoors in all kinds of weather. It’s also extremely tough and flexible and should last for years.
The company makes a variety of clear sealants, including this one, which is the most popular.
Gorilla Waterproof Caulk & Seal 100% Silicone Sealant, 10oz Cartr
Things That Make It a Good Investment
The Gorilla 100% Silicone Caulk and Sealant is our pick for sealing an aluminum roof because it’s formulated to be completely waterproof (and pressure-resistant, too) for as long as you need it to be. It fully cures in 30 minutes, so you can use it on an emergency repair, and it stays watertight for years.
The clear version of this caulk has a remarkably low amount of early yellowing, compared with other clear caulks we tested. It also doesn’t shrink, crack, or become brittle in cold temperatures, and it resists mold and mildew better than most other clear caulks.
We also tested the white version of this caulk; it’s more expensive but is more resistant to yellowing than clear caulks. If you’re concerned about aesthetics or want to mask an imperfection in the caulked area, white is the way to go.
What to Look for Before the Purchase
We focused on roof coatings that were formulated for use on metal surfaces to reduce corrosion and prevent leaks. Some roof coatings may be labeled as metal-friendly, but we avoided those with only that label.
Based on our interviews with experts, comparisons of brand specifications and owner manuals, and our own research, we determined the following criteria to be most important:
Ability To Seal And Protect Against Corrosion
Coatings that don’t have zinc or aluminum oxide—two of the most common ingredients in roof sealants—won’t adequately protect steel or aluminum from moisture. For steel roofs, follow this guide specifically.
Ability To Withstand Extreme Temperatures
Most roof coatings are formulated to withstand temperatures between -40°F and 160°F. Some manufacturers list even higher maximum temperatures, but these claims are usually made for commercial products; residential coatings usually top out at 120°F.
A coating that can withstand extremely hot temperatures will likely work just as well at lower temperatures.
Frequently Asked Questions
What type of sealant is best for aluminum roofs?
Silicone based sealant is the best type of sealant for aluminum roofs. It provides superior adhesion and is resistant to extreme weather conditions and temperature changes. It is also resistant to UV light and water damage, making it an ideal choice for aluminum roofs.
How long will the sealant last on an aluminum roof?
The lifespan of sealant on an aluminum roof will depend on the type of sealant used and the environmental conditions in which it is applied. Generally, roof sealants can last anywhere from 5 to 10 years, but may need to be re-applied more frequently in harsher climates or if the aluminum roof is exposed to frequent sun, wind, or rain.
What are the advantages of using a sealant on an aluminum roof?
The advantages of using a sealant on an aluminum roof include:
- Improving the overall durability of the roof by creating a waterproof barrier that seals out moisture and prevents corrosion.
- Enhancing the appearance of the roof by creating a glossy finish.
- Preventing debris, dirt, and dust from entering the cracks and seams of the roof.
- Increasing the energy efficiency of the roof by preventing air leaks.
- Reducing overall maintenance costs by providing an extra layer of protection against the elements.
Is a sealant necessary to protect an aluminum roof?
Yes, it is recommended to use a sealant on an aluminum roof to prevent corrosion and keep it in good condition. The most common type of sealant used for aluminum roofs are silicone sealants, which provide a waterproof barrier and help protect the roof from the elements.
Can the sealant be applied in extreme weather conditions such as extreme heat or cold?
Yes, the sealant can be applied in extreme weather conditions such as extreme heat or cold. However, it is important to note that the temperature should not be below 40°F (4.4°C) or above 90°F (32°C). Additionally, the area should remain dry and free of debris during application.
