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Flex Seal for Roof: Is It Effective?

flex seal for roof is it effective

The Flex Seal for Roof is a new innovation in the roofing industry and has been getting mixed reviews. Is this product worth investing in?

Read on to find out more about what customers have had to say about it!

What is a Flex Seal?

Flex Seal is a liquid rubber sealant that can be applied to almost any surface, including metal and plastic. It’s made from the same material as car exhaust pipes! 

This product promises to keep your home waterproof for up to ten years, although it should only be used on surfaces you don’t mind getting dirty.

Container of professional polyurethane foam sealant

Ingredients of Flex Seal for Roof

According to Flex Seal official website, the solution is composed of mostly water and rubber solids which are “fully resins with additives.”

Some of the ingredients include Acrylic Polymer emulsion, Ethylene-Vinyl Acetate Copolymers, Rubber latex. 

Other than that, additional components of Flex Seal include minerals that act as stabilizers, 2-butoxyethanol, and a preservative – Benzisothiazolinone.

2-Butoxyethanol is a solvent that can be hazardous to humans by ingestion, inhalation or skin absorption. It is also harmful if it gets into the eyes.

Symptoms from exposure include headache, fatigue, weakness, nausea and vomiting. Breathing the chemical compound can potentially lead to respiratory system failure.

People with liver or kidney problems should refrain from using Flex Seal, as these organs are responsible for metabolizing harmful chemical compounds.

Pregnant women and children should pay special attention, as 2-Butoxyethanol is especially dangerous for fetal development.

Roofing from roofing felts and resin. Sealing roofing material

Things to remember when using Flex Seal for roofing

• Flex seal is not a replacement for your roof or gutters.

It can only seal small cracks and holes, while it will do nothing to repair missing shingles or large gaps in the roof. They should be fixed by professionals before using flex seal on them (see below).

• Do not use flex seal on the roof in extremely hot or cold weather, when rain is expected to fall, or when it has rained recently.

• Using a flex seal on your roof before painting it will keep the paint from sticking properly to the surface.

Flex seal also needs to be applied directly onto clean surfaces, so any old paint layers should be swept away before applying.

• Every can comes with a brush attached to the lid, and while many roofs only require it to be applied in small areas, you may want to get extra brushes for any larger jobs.

Additionally, some users agree that using a roller is also easier than using a brush (although these are not included).

Steps on how to properly use Flex Seal for roof

Here are the steps of using Flex-Seal for your roofing material:

1. Make sure that the area applied with this liquid rubber is clean and dry. Use a broom or a clean rag to remove any debris, leaves, rust, dirt, dust, etc.

2. Shake the can for three to five minutes or until the sealant is completely dissolved inside the container.

3. Cut off the nozzle’s tip with a pair of scissors and use it to apply Flex Seal on all areas that need treatment.

4. If additional coverage is required, just cut-off another hole in the nozzle’s tip and use a new nozzle for a second coating. Apply enough sealant to ensure that no dripping will occur during application.

5. Wait for at least 30 minutes before the Flex-Seal has dried completely or as directed by your product’s label instructions.

6. Clean any excess sealant from the gutter, downspout, skylight or other drainage areas.

7. After using the sealant, you can spray water to ensure no cracks are visible on your roofing structure.

8. It comes in a very wide variety of colors so it’s easy for any homeowner to find their preferred shade. For instance, Flex Seal is also available in almond, black, blue, brown, bronze, copper, gray, green. pink, red and yellow.

Roofer make repair

Is Flex Seal Effective?

Flex Seal is an effective solution for fixing roof leaks. It is a rubberized coating that can be directly applied to the structure.

However, this kind of product should only be used as a temporary and quick fix for roof repairs.

Flex Seal can stay up to 2 years if properly maintained; but again, it will depend on the condition of the roof.

It is also not advisable to use it on low slope roofs or roofs with heavy snowfall, as the Flex Seal’s adhesion may be affected by external elements. 

The user should ensure that he will apply the product correctly to achieve satisfactory results. The user manual comes very handy when applying the product for the first time.


What Do People Think of It?

People who have used the product give mixed feedback on its effectiveness. Some customers say that they’re very happy with their purchase because it kept water from leaking inside for a long period of time. 

Others complain that after just one downpour, the Flex Seal has completely worn off and they’re back to square one.

Is it hazardous?

Flex Seal is considered safe for surfaces, but it is recommended that users verify the product label to find out if the product is safe for their specific use.

Flex Seal can be used outside on certain surfaces, but not all surfaces. 

It is not recommended for aluminum, glass, rubber, Mylar or plastics. It can be applied to wood but should not be used on painted surfaces as it may damage the paint.

If a surface has come into contact with grease or oil, Flex Seal will create a slippery surface and users should exercise caution.

Is It Worth The Money?

Whether or not you should invest in this product depends on your expectations.

If you want a quick fix for all of your roofing problems, then perhaps spending $20 on some Flex Seal is worth it; however, if you want a product that will truly protect your roof, then it’s probably best to look into getting some professional help.

roof repair with sealant

Final Thoughts

Flex Seal is a good product for those looking for an immediate solution to their roofing problems.

It works as advertised and can be applied quickly and easily with no training needed; but it’s not intended to last very long. 

If you want something that will truly protect your roof, then look into getting professional help or contacting the manufacturer directly regarding warranty information.