Wood repairs are inevitable, as scratches, gouges, and holes can appear as time goes by or simply by continuous use. 

Luckily, however, there are various ways to take care of these imperfections, with wood filler and wood putty being the most popular options.

Deciding between wood filler and potty can be quite tricky, especially since some people confuse the two materials, thinking they’re the same thing. 

In this guide, we’ll walk you through everything you need to know about the two materials and the right situations and purposes to use each one. Let’s dive right in! 

Wood Filler vs Wood Putty – How They Differ

To help you make an informed decision between the two materials based on your needs, here’s a brief overview of the differences between the two materials.

Composition

Wood filler is a paste-like material, typically made from wood fibers like sawdust mixed with binders and resin that harden with time. These binders can be either water-based or solvent-based.

It comes in a variety of colors to match different types of wood tones. Wood filler is typically available as a powder that you mix manually but you can also find pre-mixed combinations.

Since you mix it yourself, it gives you more versatility when it comes to its hardness-to-pliability ratio.

On the other hand, wood putty is a mixture of different types of chemicals and binders along with coloring agents for uniformity. These ingredients have a unique consistency, which is why they’re also known as “wood plastic”.

Like wood filler, putties also come in a wide range of wood tones, depending on the pigment used to color them.

Compatibility with Wood

While both wood filler and wood putty are designed for use with wood, they’re compatible with different types of wood.

Since wood filler has a large concentration of wood fibers, it bonds very well with unfinished (unstained) wood. However, you can also use wood fillers on finished wood but you’ll need to sand and refinish it after because it’s not water-resistant.

As for wood putty, it’s primarily used for finished wood. This is because it forms a good adhesion to the existing finish but doesn’t create a strong bond with the bare wood beneath.

Durability

The durability of wood fillers heavily depends on the product in question. For instance, Durham’s Water Putty is designed to become incredibly hard when it dries, especially after sanding and sealing. This makes it ideal for a variety of applications where a rock-solid bond is critical.

On the flip side, wood plastic is known for being less durable, so it’s more prone to nicks and scratches, particularly on frequently contacted surfaces or areas exposed to impact. That’s why it may require frequent touch-ups to maintain its look.

Pliability

As previously explained, the pliability of wood fillers varies depending on the specific type you’re using. Some are formulated to be quite stiff for the precise filling of larger holes, while others favor flexibility for better control when working with intricate details.

Wood putty, on the other hand, is known for its superiority in terms of pliability. Wood putty would even retain some flexibility after drying. This allows it to accommodate the subtle expansion and contraction of wood when temperature changes.

That being said, both wood filler and wood putty are fairly easy to spread into tight corners and cracks before drying, so you won’t have a hard time working with either.

Sanding

A crucial advantage of wood filler is the ability to sand it smooth after it dries, thanks to how hard it gets. This gives you a flawless finish that seamlessly integrates with the surrounding wood.

However, if you’re working with wood putty, sanding is typically not required and not recommended due to its softer composition. 

Sanding won’t only create a mess but it can further increase the imperfections if you’re not careful.

Drying Time

Wood filler dries relatively quickly, typically within 30 minutes to a few hours depending on the type you’re using and the thickness of the application. 

The reasonable drying time allows you to work easily as you’re not rushed but also don’t have to wait long until the hole is patched.

Additionally, you can revive it by adding some water to continue working on it, provided you didn’t stain it yet.

As for wood putty, the formula can take a noticeably long time to cure, and even then, it doesn’t harden all the way.

Shrinking

Wood fillers can exhibit some shrinkage as they dry, although this typically depends on the formula and moisture content before drying. This shrinkage may require adding some extra filler to keep the surface smooth before sanding.

When it comes to wood putty, shrinkage is rarely an issue because it remains largely flexible even after drying.

Outdoor Use

Water-based wood fillers don’t hold up well against outdoor weather, especially if it rains and snows. If you’re doing an outdoor repair, you must sand and paint the area to protect it from the elements.

This is typically less of a problem with solvent-based wood fillers, as they’re naturally more resistant to water.

On the other hand, wood putty’s chemical composition makes it a great option for outdoor use, although you should still check the specific instructions of the product you’re using to make sure it’s suitable for outdoor applications.

Painting

You can easily paint wood fillers after sanding them to ensure a color-matching finish. Since it contains wood fibers, stains will also integrate smoothly with the filler and surrounding wood.

Similarly, you can paint areas where wood putty is added. However, if you compare wood putty vs filler side by side, you’ll notice that the paint doesn’t adhere uniformly to putty.

Luckily, wood putties come in a variety of tints and colors to match various wood tones, so you may not need to paint them.

Versatility

Both wood filler and wood putty are excellent at doing their jobs. However, wood fillers are slightly more versatile when it comes to uses.

Let’s take Durham’s Water putty vs Bondo as representatives of each formula. In that case, you’ll notice that Durham’s Water putty can also work with drywall, plaster, render (stucco) concrete, siding, and much more.

On the other hand, Bondo is suitable for wood, metal, concrete, and fiberglass, but it’s not as durable so it doesn’t always work as intended.

What is Wood Filler Used For?

Wood filler comes in handy for a variety of tasks related to repairing and restoring unfinished wood. You can use it to fill gaps and holes as well as large gaps in unfinished furniture, trim, cabinets, or flooring.

You may also use wood fillers to smooth out rough spots or imperfections on wooden surfaces before sanding and painting.

Moreover, it works well with chipped or damaged edges on furniture, shelves, or countertops, by molding the paste-like material to reshape it and restore the lost form.

This also works with artworks and woodworking projects that require decorative accents and molding.

Wood Filler Pros and Cons

Here’s a quick look at the main advantages and drawbacks of using wood fillers for your next project:

Pros

• Easy to sand and paint after applying
• Hardens into a solid, durable surface
• Available in various types for a wide range of choices
• Easy to store and allows you to create enough patches for your work
• You control its hardness by mixing it with water
• Doesn’t take long to dry out completely
• More versatile with applications and compatible surfaces

Cons

• May not work well with finished wood
• Requires painting and staining after use with exterior application (not resistant to water)
• Some varieties may shrink and crack after time
• Doesn’t expand with changing weather

What is Wood Putty Used For?

Wood putty shines when you’re working with an already-finished wood surface, particularly for minor imperfections.

The classic use of wood putty is to fill scratches and nail holes. The pliability of the putty allows for easy application, which is reliable when working with furniture, cabinets, trim, or doors already in place.

Besides wood, you can also use some types of wood putties with other materials, especially to fill up thin cracks.

Since sanding isn’t recommended, you still need to choose a putty color that closely matches the finished surface for a seamless repair.

Wood Putty Pros and Cons

Lastly, here’s an overview of the reasons why you should use or avoid wood putty:

Pros

• Fairly affordable
• Easy to use directly, as it typically comes premixed and ready to apply
• Can serve as an adhesive because it sticks well to pained surfaces
• Comes in various colors and tones to match the surface
• Flexible and doesn’t shrink with time
• Fairly resistant to moisture, so it works for outdoor projects

Cons

• Can’t be sanded or stained
• Doesn’t work well with paint, so you have to pick the closest matching color
• Takes very long to dry, and stays relatively soft after drying
• Doesn’t work with unfinished wood because it can damage its fibers

TL;DR

Choosing between wood filler and wood putty depends on the condition of the wood surface and your desired outcome.

Wood filler is ideal for repairs on unfinished wood, as it hardens quickly and retains its durability, allowing for sanding and painting to achieve a flawless finish.

On the other hand, wood putty excels at addressing minor blemishes on finished wood, but it takes quite some time to dry and doesn’t harden fully.

If you’re looking for a durable, long-lasting repair, we highly recommend Durham’s Rock Hard Water Putty. Besides drying quickly and offering superior durability, it’s highly versatile and works with a huge range of materials.