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Should I Fill Cracks In Wood Deck? (And What Filler To Use)

Having a deck gives your home additional living space and room for family, friends, and guests. Like most structures around the house, a deck is prone to wear and tear that require maintenance. If you're wondering whether or not you should fill cracks in your wood deck, you're in the right place! We have researched the topic and the appropriate fillers to use.

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Maintaining your wood deck regularly should be a priority to preserve its structure and function. You can fill the cracks in the deck either with wood putty or wood filler.

Wood crack fillers can improve the overall appearance of your deck. You have to properly apply the substance to ensure its durability and longevity. Continue reading as we discuss the maintenance of your wood deck and related topics.

Applying putty on holes at the wood deck, Should I Fill Cracks In Wood Deck? (And What Filler To Use)

Why Should I Fill Cracks In Wood Deck?

Wooden decks are prone to cracking because of their constant exposure to heat, moisture, climate, and weather. This phenomenon is a natural occurrence in wood, but do not worry! It can be easily fixed.

Filling cracks is important in preserving the overall durability and function of your deck. It can last for years if properly maintained with sealants and other materials used to fill damaged portions.

By doing this, you can avoid replacing damaged boards and even the entire structure! Fixing your wooden deck ensures that the space is a much safer place for you and your family.

What Fillers To Use?

There are various wood hole fillers you can use. Proper application is necessary to ensure its overall quality.

Wood Putty

Wood putty is made up of plastic-based and oil-based substances such as calcium carbonate, colorants, and linseed oil. Because of its chemical composition, it is the best filler to use in exterior wooden structures such as your deck.

It dries relatively slowly, but it does not crack, shrink, or expand when temperatures fluctuate. Even after the putty hardens, it is still quite flexible and can be used for outdoor repair work.

A putty's chemical composition can damage wooden structures. Before application, it is necessary to stain the wood to create a protective layer between the putty and the exposed wooden portion.

Check out this all-purpose putty on Amazon.

Wood Filler

Applying wood filled between the gaps of the wooden floor

Wood filler is composed of resins (a thick sticky liquid substance) and pulverized wood derivatives that harden within minutes.

Because the substance dries in a matter of minutes, it is not flexible and remains rigid so it can crack if the wood began to expand or shrink.

It can be used in simple exterior repairs. However, you should apply the material to the interior wooden structures of your home.

While wood filler adheres tightly to the wood, it does not increase the overall strength of the material, but it does help in preserving the structure. It is ideal for filling narrow cracks and holes. Because of its composition, the material is relatively easy to apply.

Check out this all-purpose wood filler on Amazon.

Wood Glue And Sawdust

A huge pile of saw dust

You can make your own wood filler from wood glue and sawdust. Creating your own filler gives you the advantage of matching the substance with the color of your woodworking material.

This is done by blending sawdust from the same wood with a binder or glue. This wood filler is ideal to use for repairing small cracks and holes.

It is not suitable for bridging large gaps and crevices because the material itself does not make the wood's composition more durable. It only aids in preserving the structure.

Applying wood glue of a wooden work piece

How To Apply The Right Filler

Follow these steps to fill the cracks on your wood deck:

Mix Your Filler

The chemical tends to separate when the filler has not been used for a while. Mix the substance thoroughly in the container using a putty knife. Continue mixing until it becomes smooth and thick and reaches a uniform color.

Apply The Substance

If you are using wood putty, you have to stain the damaged portion first before applying the substance.

Firmly thrust the filler deep into the crevice using a putty knife. Quickly flatten the wood filler, then remove any excess. When scraping the surface, be careful not to poke or gouge the repaired area.

You should immediately wash the putty knife with warm water and soap. Once the filler dries, it becomes challenging to remove it from tools.

Wipe Off Excess Filler With Your Finger

You have to firmly press the substance deeper into the gap using your finger. Once finished, wipe or remove any excess filler.

Smooth The Surface

Wait for at least 30 minutes to an hour before sanding the patched area. When using putty, let the substance sit for 72 hours to ensure that it will harden.

Sand the surface in the same direction as the wood grain to ensure that the substance blend with the wood, giving it a more natural appearance.

Afterward, wipe the area with a tack cloth. This helps remove dust particles caused by sanding and prevents the patched area from having a lumpy or grainy appearance.

Other Maintenance Problems for Wood Deck

A wooden deck at the back of a house

Aside from cracks, you may have to deal with these issues in your wood deck:

Discoloration of Wood Boards

Discoloration is not a safety concern, but it is certainly not attractive. Outdoor wooden decks are frequently exposed to the elements. The main cause of deck discoloration is sunlight.

To fix it, remove any previous paint, clean the wood, and apply a deck stain with effective UV protection.

Slippery Surface

Too much algae or moisture can make your wood deck slippery. The best solution for this is to do a through pressure-washing every year.

Give the floor a good washing, ideally with a power washer, to allow the wood's natural grain to add extra traction and slip resistance.

Old Wooden Boards

Moisture and insect infestation can cause wood to rot. To fight this problem, remove the damaged portions of the wooden board and repair them.

To accomplish this, carefully scrape away the rotten wood using a screwdriver. You should treat wood rot one board at a time because if it is left unattended, it can spread and lead to major structural degradation.

Large Gaps

The gaps between the deck boards will grow bigger and be more problematic over time as a result of the wood's inevitable shrinkage. Big gaps can be dangerous since and become a tripping hazard.

If the gap is big, you can no longer use the board. Instead, you should buy a new one. Remember that wooden boards have a range of moisture content depending on how they are treated and dried. This prevents possible gapping between your deck boards.

Wobbling Wood Deck

Poor installation, termite infestation, and wood deterioration can lead to a wobbling deck. You should replace your deck right away and contact a qualified expert who can address the problem.

How To Create Your Own Wood Filler

You can create a wood filler form scrap wood, craft stick, and wood glue. You need an electric sander, file or rasp, and putty knife to prepare the filler. Once you have the tools and materials for the project, you can proceed to do the following:

1. Make sawdust

The first thing you will need in creating wood filler is sawdust. Ensure that the dust matches the patched-up area.

You can collect the sawdust through a power sander, but if you don't have one, you can sand by hand or with a file or rasp. You can also use an electric miter saw to make sawdust without wasting wood.

2. Mix the wood filler

Create a small pile with the cleaned sawdust. Add wood glue and stir with a craft stick. Continue adding glue until the mixture resembles thick putty (similar to cookie dough in consistency).

Applying the dough to the work surface will be challenging if it has already started to firm. If this occurs, start over with a fresh batch and slightly up the wood glue content. Apply the filler to the work material as soon as the desired texture is obtained.

Why Are My New Deck Boards Cracking?

Wood shavings stored inside a box

Your new deck boards be cracking because they are not pressure treated and because of temperature fluctuations. Natural wood expands and shrinks while treated lumber does not.

Moisture caused by rain and snow penetrates deep into untreated lumber, causing wood expansion. When the weather becomes warm, moisture dries out, causing wood contraction. This natural phenomenon will eventually result in cracking.

In Closing

Applying putty on holes at the wood deck

If you have noticed any damage to your wood deck, take action quickly to prevent any further damage. Hopefully, this article has helped with our discussion on the ways to repair your cracked wood deck.

Before you go, you might want to check these related posts:

8 Best Wood Fillers For Large Holes

How Long Does It Take For Wood Filler To Dry?