Is five minute epoxy waterproof?

Epoxy is one of the most commonly used adhesives in manufacturing, construction, and maintenance. It’s a two-part substance composed of an epoxide resin and a polyamine hardener.

When combined, the two parts form an incredibly strong adhesive bond that’s difficult to break.

Five minute epoxy is just what it sounds like: quick-drying epoxy that takes five minutes to harden. Epoxies need time to set so that they form a strong enough bond to be useful (if you’ve ever tried to put together IKEA furniture, you’ll remember your frustration when the screws wouldn’t tighten properly because the wood glue hadn’t dried).

While other brands of epoxy have drying times ranging from 20-120 minutes or more, five minute epoxy is suitable for applications where a durable bond needs to be formed very quickly.

For people who work with raw materials every day or who dabble in DIY projects around their home, five minute epoxy can be indispensable—for example, if you want to fix something while on vacation but don’t want to wait hours for it to dry properly.

But are there any downsides? Can you even get fully waterproof results with this type of glue? Yes—and we’ll show you exactly how!

Is epoxy good for waterproof?

Epoxy is one of the best waterproof adhesives on the market. In fact, there are many places you could use epoxy to waterproof your home or building and protect it from water damage.

  • Fill Cracks in Concrete – Epoxy can be used to fill cracks in concrete caused by cold weather or a shifting foundation. It’s easy to apply, cures quickly and doesn’t shrink.
  • Seal a Leaky Shower – Use epoxy to repair tiles in a leaky shower. You can also use it to seal around plumbing fixtures and even fix leaking toilets or sinks.
  • Seal Basement Floors – Epoxy acts as a protective barrier against moisture that could seep through basement floors and cause mold, musty odors and other damage.
  • Protect Wood – Use epoxy as a protective finish on wood surfaces exposed to water, such as boat parts, countertops and more. Epoxy will not only make them waterproof but strong enough for frequent use.

How long before epoxy is waterproof?

So, you have an epoxy project. Whether it’s a necklace, earrings or something more complicated, you’re ready to go! You’ve got everything out on your work table: the epoxy resin, hardener and the object(s) that need to be waterproofed. You mix it up and pour it into your mold (or onto your surface).

There are bubbles that form and suddenly you realize: how long do I need to wait until this is waterproof?

The short answer is: not 5 minutes. One of the most common misunderstandings about epoxy resin is that 5 minute epoxy is ready in five minutes. At first glance, it sounds right—after all, if 20 minute epoxy takes 20 minutes to set up and 30 minute epoxy takes 30 minutes, then 5 minute epoxy should take 5 minutes to set up—right? Well…not exactly.

Is epoxy compound waterproof?

It is best to use an epoxy that is waterproof. This protects the item that you are applying it to as well as making sure it will last for years. Epoxy compounds create a strong, long-lasting bond that also resists moisture, heat, and chemical damage.

When epoxy sets up and dries, it forms a hard, durable surface that is resistant to scratches, dents, and other damage from everyday wear and tear.

You can find many different types of epoxy at your local hardware or paint store. Epoxy compounds have been around since World War II when they were used to seal aircraft fuel tanks and coat metal parts in military equipment.

Today epoxies are still used in everything from airplane construction to marine applications including ship hulls, propellers and other underwater structures like docks or piers because of this durability under extreme conditions such as salt water exposure or constant moisture exposure outside of naval installations all over the world!

Does epoxy hold underwater?

Epoxy is a popular adhesive that’s ideal for many different applications. But does it hold up underwater? Well, the short answer is… No.

Five-minute epoxy has been tested by scientists and it does not hold up if you submerge it in water. It also isn’t very effective on wet surfaces or surfaces that are exposed to water.

The long answer is more complicated—let’s take a look at why five minute epoxy doesn’t work under water and how one might still use it in certain situations when there’s a chance of exposure to water.

Will epoxy hold up outdoors?

I recently discovered that the epoxy we used to seal the concrete floors in our outdoor porch and shed is able to hold up even in a harsh environment. In the past, I have mentioned this epoxy as being “waterproof” or “water resistant,” but it turns out that its true flexibility is what allows it to withstand the test of time.

The reason that epoxy takes so long to cure is that it needs days of sun exposure before it will be able to resist water without becoming brittle and cracking.

Is epoxy good for outdoor?

It can do so much! And it’s waterproof, so it holds up well outdoors. You should use it to seal cracks and fix broken items. Use epoxy to repair wood, glass, and plastic.

Get more ideas on what you can do with five minute epoxy from the list below:

  • Seal cracks in a flower pot or vase
  • Glue broken pieces of your favorite ceramic mug back together

Will epoxy set in cold weather?

Temperature is another factor that affects how epoxy sets. The colder it is outside, the longer it takes for the mixture to get hard.

In general, the temperature shouldn’t drop below 32 degrees Fahrenheit if you don’t want your epoxy to set properly.

If this happens, the mixture will become a gooey mess and will never cure. It’s not easy to work with epoxy in cold weather because of this reason. You should always watch what you are doing and take note of the temperature around you when using epoxy glue.

What is 5 minute epoxy used for?

Epoxy is a type of plastic resin. The most common epoxy is called “5 minute epoxy”. This adhesive and sealant have many uses, including:

  • Repairing or building surfboards
  • Protecting and waterproofing electrical wire connections
  • Making jewelry, carvings, sculptures, rings
  • Building model airplanes
  • Attaching broken ceramics or china back together

Additionally, 5 minute epoxy has the following features:

  • It bonds well to most surfaces (a few notable exceptions are polyethylene and polypropylene plastics).
  • It is clear and colorless once it dries.
  • It has an odor that some people don’t like.
  • It will not work if the temperature is below freezing (32 degrees F / 0 degrees C).
  • It starts drying in five minutes but requires 24 hours to cure completely.


If you have waterproofing needs, five minute epoxy is a great option. Make sure to consider the environment in which your project will be used and select the best product for that situation.

If you have any questions or need guidance, please feel free to reach out to us!

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Martin Flood

Martin Flood has been working in the construction industry for over 20 years as a general contractor with expertise in remodeling projects that are large or small. He has furthered his career by specializing in epoxy resin flooring, providing excellent service to both commercial and residential clients. Martin’s experience enables him to offer professional advice on how to choose the right type of project based on your needs and budget.

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