Can You Use Flex Seal On Rotted Wood?

flex seal on rotted wood

Flex Seal is a sealer that works pretty well with PVC, copper, metal, and wood. It is used for repairing and protecting materials from environmental elements like moisture.

Even though we generally use Flex Seal on our fresh woodworks and furniture stuff, have you ever thought about using Flex Seal on rotted wood to avoid wood getting damaged any further?

So, let’s find out, Can you use Flex Seal on rotted wood?

Never use Flex Seal on rotted wood to prevent wood rot because the moisture is already gone inside of the wood. The Flex Seal stops moisture from evaporating and can cause rot faster because moisture is trapped inside. Repair the rotted wood first and then apply Flex Seal to make the wood water resistant.

But that’s a quick snapshot and there’s a lot more to know about Flex Seal on rotted wood.

In this article, we’ll explore whether can you use Flex Seal on rotted wood, how to repair rotted wood and apply Flex Seal properly, does Flex Seal waterproof rotted wood, and much more.

Furthermore, I’ll answer some frequently asked questions as well.

Let’s dig in!

Does Flex Seal Work on Rotted Wood?

Yes, you can apply Flex Seal on rotted wood, it seals the wood and doesn’t give moisture a chance to get inside of the wood. But the thing is, the problem has already happened.

The moisture is already inside the wood. You cannot ignore that just by applying Flex Seal paste from the outside.

The Flex Seal will also stop moisture trapped inside of the wood from evaporating. This makes the moisture inside nowhere to go.

So, they’ll soak deep into the wood fibers and rot the wood. This will never stop until the wood gets fully dried. The wood will begin to rot faster than before.

Eventually, after applying Flex Seal on rotted wood, the wood will get into a much worse situation because the moisture will destroy wood from inside.

Therefore, never apply Flex Seal on rotted wood, instead of stopping the wood from rotting, you’re cooperating with the rotting process.

But after repairing the rotted area and then applying Flex Seal over the whole woodwork or furniture, you’ll be able to stop moisture from getting inside of the wood and stop wood rot in the future.

Flex Seal fills gaps and cracks of rotted wood and seals the wood perfectly.

So, let’s have a look at the advantages and disadvantages you’ll get by applying Flex Seal on rotted wood.

Pros and Cons of Using Flex Seal on Rotted Wood

Prevent outside moisture from getting insideWood rot faster than before
Protect wood from UV lightInside moisture doesn’t evaporate
Protect wood from insects and bugsRuin the interior structure of the wood
Able to use for rotted wood in good conditionUnable to protect the wood that rotted worse
Fill cracks and gaps 
Seal the wood 

As you can see, you can use Flex Seal on rotted wood only if the wood is not in such a bad condition.

If the rotting is affected to a small area, the other areas of the wood can be protected and sealed with Flex Seal.

But if the wood is rooted so badly, nothing can help you until you repair the wood fully and then apply the Flex Seal.

How To Use Flex Seal on Rotted Wood?

You can only apply Flex Seal on rotted wood by repairing the rotted area first and then applying the Flex Seal over the wood.

So, let’s see how it should be done.

Supplies You Will Need,

  • Flex Seal product
  • Rotted wood
  • Damp cloths
  • 220 grit sandpaper
  • Gloves
  • Hammer
  • Paintbrush

Here’re the steps you need to follow when using Flex Seal on rotted wood,

  1. Let the wood dry completely
  2. Remove rotted area
  3. Clean the wood
  4. Sand and remove sawdust
  5. Spray or apply Flex Seal
  6. Let it dry and cure

So, let’s discuss each of the above steps one by one to get a clear idea about using Flex Seal on rotted wood,

1. Let the Wood Dry Completely

First of all, let the rotted wood dry completely to evaporate the moisture inside.

This can take days or weeks depending on the wood type and moisture content inside.

Place the rotted woodwork or furniture in a well-ventilated dry area and let it dry out completely. Because rotted areas will be easily removed when the wood dries.

2. Remove Rotted Area

Now claw out the rotted area using the hammer. Place the claw of the hammer at the base area of rot and apply pressure to pull the claw towards you to remove the rotted surface.

Do the same procedure with the hammer again and again until the rotted area removes completely because it is so difficult to apply Flex Seal on rotted surfaces.

Make sure not to apply too much pressure on the hammer because that can damage the healthy wood parts.

Only the unstable wood needs to be removed.

3. Clean the Wood

After removing the unstable rotted wood areas clean dust and debris off the whole wood surface with damp cloths.

Because dust and debris get trapped inside the Flex Seal coat you won’t be able to achieve maximum performance.

Wipe down the entire surface with a clean rag without missing any spots.

Make sure not to use cleaning solutions to clean the wood because, after removing the rotted area, there’s a high possibility of absorbing water into the wood because wood interior fibers are widely open to the outside world.

Therefore, better to do clean and dry without using water.

4. Sand and remove Sawdust

After cleaning the wood properly, sand the entire surface with 220 grit sandpaper to make the surface smooth. After removing the rotted area, the surface will be so random and dull.

Therefore, sanding is highly recommended to make the surface ready to accept Flex Seal evenly.

Sand along the direction of the wood grain to avoid wood from scratching. Use finer-grade sandpapers because higher-grade ones can damage the sensitive areas of the wood.

Once you’re done with sanding clean the whole surface with a damp cloth to remove sawdust. Now you have a nice, smooth, and clean surface to accept Flex Seal without no issues.

5. Spray or Apply Flex Seal

Shake the flex spray can vigorously for about a minute and aim the nozzle of the spray at the cracks and gaps of your previously rotted wood furniture.

Then spray Flex Seal in sweeping motion by keeping a distance of 10 – 12 inches.

Flex Seal fills cracks and gaps of rotted wood and makes sure to spray slowly until fills all the gaps and cracks.

Make sure not to miss any spots because once the Flex Seal is settled in, it’s a bit difficult to identify the missing spots.

When spraying Flex Seal, you’ll notice it can perfectly fill up the rotted areas without showing any difference from the healthy areas of the wood.

Therefore, Flex Seal works really well in rotted wood once the wood is fully repaired.

Apply 3 coats of Flex Seal on rotted wood to get the results you want.

The first coat of Flex Seal penetrates through wood fibers and the second coat of Flex Seal bonds with the first coat and seals the wood.

The third coat of Flex Seal is useful to protect the wood from UV light, moisture, and other environmental elements.

6. Let it Dry and Cure

Let the Flex Seal settle and dry for about 24 hours before applying the next coat of Flex Seal.

After applying all the coatings of Flex Seal let the rotted wood dry for about 24 hours and allow it to cure for about 48 hours before using it.

Never apply another coat of Flex Seal once the previous cost is still wet because the trapped moisture between two layers of Flex Seal can penetrate through wood fibers and can cause wood to rot.

Then you’ll have to start everything from the beginning and the appearance of the woodwork will be ruined as well.

Drying time and curing time can vary due to the wood type, environmental humidity, and climate changes.

Usually, it takes more time to apply Flex Seal on healthy wood than apply Flex Seal on rotted wood because of the high drying time.

That’s it, folks! Now you know how to use Flex Seal on rotted wood correctly without making any errors.

Make sure to do the job correctly from the first attempt because Flex Seal is significantly higher than other finishers like epoxy.

So, let’s answer some frequently asked questions about using Flex Seal on rotted wood.

How Long Does Flex Seal Take to Dry On rotted Wood?

Flex Seal takes 2 – 3 hours to dry on rotted wood while it takes around 24 hours to fully cure.

But drying time is hugely dependent on the wood type, humidity, climate changes, thickness of the Flex Seal coating, and many more.

How Do You Know If Wood Is Rotting?

You can identify whether the wood is rotting or not by inspecting its surface. Mushroom-like fungus area with spore dust indicates that the wood is rotting.

The smell is also different from the musty smell.

Other than that, the wood discoloration, change in size, cracks, and splintering are good indications to identify the wood is rotting.

Did I cover all you wanted to know about: Can You Use Flex Seal on Rotted Wood?

In this article, we have deeply explored whether can you use Flex Seal on rotted wood, what are the pros and cons you’ll get by applying Flex Seal on rotted wood, and how to prepare rotted wood for Flex Seal.

Flex Seal works well on rotted wood only after the rotted area is repaired. Other than that, you should never apply Flex Seal on rotted wood because it’ll seal the wood while the moisture inside which will cause wood to rot faster than before. Repairing is a must before Flex Seal.

Furthermore, I’ve answered some frequently asked questions about Flex Seal on rotted wood as well.

Hope you have gained good knowledge about using Flex Seal correctly on rotted wood with the most simple and accurate method. Keep practicing!

Walter Parker is a woodworking enthusiast. He is passionate about woodworking projects & plays with woodworking tools having spent over 2 decades as a leader for Woodworking Planet. He wants to make people love woodworking! Read More About Him! Follow him on Twitter and Facebook.

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