Wood fillers can help repair holes and cracks in exterior furniture and protect them from the elements. However, choosing the wrong one can ruin your outdoor pieces or decking, costing you more time and money than intended.
So, after trying and testing various products and learning a thing or two from my mistakes, I’ve summed up the best exterior wood fillers I’ve come across.
Reviews of the Top Exterior Wood Fillers
1. Bondo Home Solutions 20082 Wood Filler
The Bondo Home Solutions 20082 Wood Filler gets my vote if you’re looking for a long-lasting exterior filler. It’s an epoxy filler that requires mixing, and as a result, it provides a highly durable fix that won’t shrink or break with time.
I’ve found it particularly effective for repairing large holes and deep fissures. Its versatility has come in handy when I’ve needed to mend gaps in everything from windows to doors and fences.
And thanks to its water-resistant construction, it can withstand the elements and is sturdy enough to be used outside. After application, it dries completely within 15 minutes.
What I Like
- The quick-drying time lets me progress with my tasks without long waits
- It's water-resistant
- I'm not frequently going back for touch-ups since this filler is so durable
- It's my top pick, especially when dealing with those challenging deeper gaps.
What i Don't Like
- Strong odor makes indoor use impractical, so it's best to work with this filler outdoors
- Keep an eye on quantity for larger projects; I've had to buy extra tubs at times
2. Minwax 42853000 Stainable Wood Filler
The Minwax 4285300 Stainable Wood Filler is one of the most multipurpose wood fillers available. With actual wood fibers in the mix, this water-based wax dries to a tough, long-lasting patch. It may be used indoors and out and accepts paint and stain well.
From my trials, I’ve been impressed by how user-friendly the Minwax Stainable Wood Filler is. Its dry texture ensures it barely shrinks post-application.
The material was so consistent that little balls could be rolled into putty-like globs and used to plug up big gaps. Given its consistency and ease of use, I’d especially recommend it to beginners looking to repair their outdoor wood pieces.
What I Like
- Application is a breeze because it smears easily
- There's no strong odor, which is great for indoor projects
- No toxic components
- The fact that it can be shaped with water comes in handy for me
- No sanding is required
What I Don't Like
- It's suitable for small gaps, so it's not the best for substantial repairs
- Patience is key as it needs time to dry
3. Elmer's Probond P9890 Interior Wood Filler
It might say “interior wood filler” on its name, but this Elmer’s Probond P9890 holds up well in outdoor applications. Real wood fibers with negligible or low volatile organic compound content are a plus for the planet.
When it is dry, you can paint over it with a color that better complements your baseboards, furniture, kitchen cabinets, and molding. It’s also great for staining since it contains many wood fibers and colors.
Additionally, it takes nails and screws. It is cheap and simple to clean up with dish soap and water.
What I Like
- It's the best exterior wood filler for the money
- I appreciate that it's solvent-free, making it safer for both me and the environment.
- Knowing that its shelf-life is unlimited is reassuring
- It's great at holding nails and screws firmly in place.
What I Don't Like
- It may take time to dry
- You may need to buy more for larger gaps
4. Abatron WoodEpox Epoxy Wood Replacement Compound
Abatron WoodEpox Wood Replacement Compound is ideal if you have deteriorating external elements that you want to revive.
I’ve successfully replaced substantial portions of decaying wood with this 2-part epoxy filler, ensuring the piece retains its original strength and beauty. What’s more, it behaves much like wood — you can paint, sand, and shape it without any hitches.
As a result of its low volatile organic compound (VOC) content, this filler has also earned GreenGuard certification (volatile organic compounds). Various wood filler products are on the market, but they often contain harmful chemicals that emit fumes and may harm the environment.
What I Like
- There are no VOCs in this filler, so it's safer for my health and the environment
- It permanently bonds to surfaces
- It holds up well against temperature fluctuations, which is especially valuable for outdoor use.
- I've found it convenient to clean up any excess filler without much hassle
What I Don't Like
- It may not adhere well to softwood
- It may take time to cure
5. DAP Inc 16Oz Latex Plastic Wood Filler
The DAP Inc 16-Ounce Plastic Wood Filler is a filler that dries to an extremely durable finish without using any water or other solvents. When dried, the filler is three times as hard as the original wood, making it an excellent choice when I need that level of durability.
The wood fibers in the filler can be sanded, machined, and painted in the same manner as solid wood.
Another highlight? If I ever need to attach something to the repaired area, this filler’s enhanced strength offers a solid base. Nailing or screwing into it is a breeze, and I’ve never faced issues of it splitting.
What I Like
- It's stronger than wood when dry
- It's designed for outdoor use
- It holds nails and screws well.
- The inclusion of real wood fibers gives it a genuine wood feel, which I love
What I Don't Like
- I noticed a bit more effort is needed when trying to spread it evenly
- There's a distinct odor when you first apply it
6. PC Products PC-Woody Wood Repair Epoxy Paste
If you need to fill in big areas of decaying wood, PC-Woody Wood Repair Epoxy Paste is the way to go.
What I genuinely appreciate about it is its high tack composition — unlike many other fillers I’ve used, it doesn’t sag or drip while drying. This filler will keep its form until it is completely dry, making it suitable for use when limited access, such as while working at heights or repairing fine details.
As a 2-component epoxy filler, it must be blended before use. It can be painted, stained, or machined after drying for about 40 minutes at room temperature. What seals the deal for me, especially for outdoor tasks, is its resistance to weather, rot, and any chemicals the wood might hold. For substantial external repairs, it’s often my first choice.
What I Like
- It's weather resistant
- No waiting game here — I could paint over it soon after it cured.
- Its high tack made it stick incredibly well
- Using it on treated lumber worked like a charm for me.
What I Don't Like
- From my experience, it's more suitable for filling those larger gaps
- I wouldn't recommend using it on certain plastic surfaces
7. Goodfilla Water-Based Wood & Grain Filler - Base/Neutral
Wrapping up my recommendations, I must mention the Goodfilla Water-Based Wood and Grain Filler. It’s ideal for skilled artisans, but casual woodworkers may put it to good use.
If you have furniture that needs fixing, a floor that needs finishing, a craft that needs finishing, or an instrument that needs designing, this is the product for you. Particularly, this is one the reliable wood fillers for floors. What I like about Goodfilla is its simplicity when it comes to sanding; it’s saved me more hours than I can count.
This excellent wood filler doesn’t shrink, sink, or crack, saving you time and money. In addition, it offers exceptional adherence.
What I Like
- I love that it's water-based, making clean-up super easy
- It's non-toxic
- Storage life is unlimited, which is great
- The custom color options were a nice touch; I got exactly what I wanted
- After it dried, sanding it was no issue at all.
What I Don't Like
- It's a tad more watery compared to some others I've tried, but it still did the job well
- Based on my projects, it seemed to shine more on those larger repairs
Exterior Wood Filler Buyer’s Guide
Exterior Wood Filler Type
Water-based
In my time working with wood, I’ve found that water-based wood fillers are incredibly convenient. They dry quickly and tend to have a subtle odor, making them pleasant to work with. Cellulose, wood fiber, and gypsum are common ingredients of these fillers.
You can dilute them with water if you need to, and you can wash them off with soap and water. Water-based wood fillers can be used for various purposes but are often reserved for indoor use.
Solvent- or Epoxy-based
Vinyl and epoxy are two examples of solvent-based wood fillers. Drying time for these fillers typically takes an hour or more, much greater than for water-based solutions.
They do have a stronger scent and can emit higher VOC emissions [1], so I always recommend ensuring your workspace is well-ventilated.
Any type of solvent-based cleaner, like turpentine or acetone, will do for cleaning up after applying a solvent-based wood filler.
However, unlike water-based treatments, these wood fillers can withstand a wider range of temperatures and humidity levels, making them ideal for use in outdoor settings.
Packaging
Containers such as tubs, tubes, and sticks are used to transport wood fillers to their final destinations. Some fillers come in tubs and require no mixing before use; they can be spread with a putty knife.
Squeezing out a tiny bit of tube filler or ripping out a small piece of stick filler and applying it by hand will do the trick when filling in small, visible imperfections.
Sticks are the cheapest and are best used for repairing scratches and cracks, while tubs, which carry the most substance, tend to be most inexpensive and are suitable for larger tasks.
Price
Unless purchased in large quantities, the average price per ounce for wood fillers is between $4 and $1.
Knowing how much wood deck filler you’ll need will help you avoid leaving projects incomplete. The sizes of fillers range from 3.5 ounces to 32 ounces.
Depending on its size and depth, you may need to search for smaller or larger sizes to have the amount you need to fix the hole.
Consistency
The consistency of wood fillers can range from putty-like to that of pancake batter. A thinner filler is largely used to fill the pores in open-grain woods, whereas a thicker filler fills voids.
Selecting the right filler consistency is crucial since larger fillers have huge particles that don’t easily fit into the porosity of open-grain woods.
In comparison, thinner fillers often lack the body to fill the pores fully.
Size and Type of the Project
Identifying the project size you need to fill is the first step. Simple fillers will do the trick if the damage is not too extensive. The larger the crack or hole, the more layers of specialized filler may be necessary to get a good seal.
Grade or Resistance
Make sure the filler you buy can withstand the elements. Because of this, you can utilize it in the open air without worrying about crumbling, splitting, or decomposing. The filler’s ability to withstand the elements depends on its resistance to water and dust.
When I buy fillers, I always double-check the packaging to ensure it’s fit for outdoor use. If it’s not explicitly stated, I’d suggest considering another option.
Paintable or Stainable?
Be sure a surface can be stained or painted to match the surrounding surface so that no evidence of the filler remains. It is important to look at the neighboring material and ensure that you can cover the filler with a similar finish.
(Check the high-quality stainable wood fillers here!)
Many wood fillers aren’t porous like wood; therefore, the surface needs to be further prepped before paint or stain can adhere properly. Here’s what you should do:
- Using sandpaper, rough up the filler and the area around it.
- You should use a primer over the filler and the surroundings. It will result in a flawless surface that hides the filler beneath the paint.
- Put on the paint per the can's instructions.
Dry Time
When working with wood filler, it’s easy to make the mistake of either rushing the drying process or waiting too long. It may take several hours for goods like epoxy fillers to dry and at least another day to cure completely.
It’s best to check the forecast before attempting exterior repairs that include these chemicals to ensure that the wood filler will not get saturated before it has time to set and cure.
To learn more, read this article on how long does it take for a wood filler to dry.
Will it Shrink or Crack?
Knowing how the filler’s potential for cracking or shrinking may affect the repair is important. If the area is adequately prepared beforehand, you shouldn’t have any issues.
The filler won’t adhere well if there is rotten wood, dirt, or dust on the surface. I advise that you clean the surrounding region as well. This way, subsequent shrinking and cracking should be less likely to occur.
How To Use Exterior Wood Fillers on Decks
Necessary Tools
- Sandpaper
- Putty knife
- Stiff brush
- Deck Cleaner or Stripper
- Exterior wood filler
Step #1: Clear the Wood
From my own projects, I can tell you that starting on a clean slate makes all the difference. Before anything else, tackle any rotten wood. It’s a basic step, but crucial. Once you spot a dent or damage in the wood, grab a stiff brush and sweep away any debris.
Step #2: Scrape the Surface of the Wood
Maintaining a spotless deck is your next order of business. For a finished wood surface, applying a deck cleaner is the way to go. If that’s not an option, lean towards a deck stripper.
A deck remover is recommended if this is not possible. I always say: never underestimate the power of reading product instructions thoroughly.
Deck cleaners and strippers should be left to soak into the wood for several minutes before proceeding. Use your stiff brush to scrub the surface of the wood after allowing the cleaner or stripper to sit on it.
Use a hose to rinse off the substance, then let the wood dry completely before filling.
Step #3: Mix and Apply the Exterior Wood Fillers
Next, if you’re using tub wood filler, acquire a putty knife and remove some of the substance. If your filler comes in two containers, follow the instructions on the packaging when combining the two containers.
If you have the tube type, squeeze the required amount onto an empty carton or paper plate, then combine it with the appropriate wood hardener. When mixing, use a putty knife to spread the filler throughout the deck.
Before adding the final 1/8 of the filler, ensure you have pressed it down with the knife properly. Follow the same steps again until the hole is sealed and the wood is flush.
Step #4: Let it Dry
Wood fillers must dry completely before use. First, follow the label’s drying time recommendations for the wood deck filler. If the filler contracts as it cures, add an extra filler, and the curing time is extended.
If it has cured properly within the allotted time, sand it down with medium-grit paper until it is flush with the deck. The same procedure should be used if there are other holes. Once you have sanded as necessary, you can paint or stain the area.
How to Fill Cracks and Gaps on Wooden Decks
The decks will need to be fixed when they get too wide to prevent mishaps. Trust me, I’ve been there. Ignoring wide spaces can lead to accidents, so it’s vital to address them.
You can take the boards out to close spaces and put them back in. The downside is that it can be a lengthy and pricey procedure.
Then there’s the debate between wood filler and caulk. In my experience, caulk can be hit-or-miss for deck gaps. But can you replace wood filler with caulk? Read more!
After the deck is spotless, you should measure the length of each opening and cut a length of rope made from natural fiber to fit it. Avoid using synthetic rope, as it cannot be stained or painted like wood. The rope should be slightly bigger than the opening to ensure a snug fit.
The next step is to place the rope in a bucket and fill it with deck stain or paint that fits your deck. Wait an hour, and it will have reached the desired hue.
Once the rope is dry, insert one end into the hole and work your way across the board with a flat-head screwdriver. Cut the rope’s end with a utility knife, and then do the same to fill the rest of the holes.
How to Repair Decaying Wood
You can use a polyester filler to repair decayed or otherwise damaged wood.
A rotten window frame, for instance, can be fixed by using a well-honed tool to cut away the decayed sections. Finish off your work by applying a layer of hardener. The next step is to fill the void with a mixture of polyester filler and a putty knife.
What to Do if You Haven’t Used a Wood Filler Before
For those using wood filler for the first time, here are a few tricks from my playbook:
- Scrub the area to get rid of any stray nails, wood chips, or other foreign objects that could botch the filler.
- Apply a thin, even coating of filler that is as well blended with the surrounding wood to cover the damaged area.
- I recommend waiting until it's entirely dry to sand or stain.
- Wait for the first coat to dry, then add a second and repeat as necessary.
If you’re diving into the world of wood fillers for the first time, trust me, preparation is key. I remember the first time I tried my hand at it, and I can’t stress enough the importance of reading the instructions provided by the manufacturer. Each wood filler brand and type can be unique, and you wouldn’t want to botch your project right off the bat.
Here’s a little tip I’ve always found handy: test the filler on a piece of scrap wood. Not only does it give you a feel for the product, but it also ensures that it mixes well and settles with the desired finish.
When to Repair or Replace Wood
External wood can be repaired with fillers for a while, but eventually, it’s better to replace it than to keep trying to patch it up. You should replace it if the damage is so severe that fixing it could be risky or arduous.
Think about how solid decaying wood is. Putting filler in the holes might work, but it won’t necessarily remain put. If prying the wood from the primary framework requires a lot of force, it should be replaced.
Interesting Read: Make a DIY Wood Filler Without Sawdust
Wood Filler vs Wood Putty Comparison
Now, let’s clear up a common mix-up: wood filler and wood putty. Both are great tools for concealing flaws and repairing damage in wood, but they’re not interchangeable.
Wood filler consists of sawdust or wood fibers suspended in a binder. Putty is typically a fiberglass, polyurethane, or epoxy compound with a plastic-like consistency.
Here are the following distinctions between putty and filler:
- Putty is typically made with an oil base, while wood filler is typically water-based.
- In contrast to putty, a wood filler may be sanded, making it a better choice for usage on untreated wood, while putty is best utilized on polished wood.
- Only indoor woodworking jobs should utilize wood fillers, but you can utilize putty in any setting.
FAQ
What’s the best way to fill deep holes?
Epoxy, which comes in two components, can repair deeper holes. Adding the hardener and potting mix produces a form that can be shaped into holes. You can also use epoxy to repair broken door hinges and other hardware.
What’s the best filler for decks?
My choice is Elmer’s Probond Wood Filler because it effectively addresses both concerns. Using the best sander, you could sand the deck and refinish it once you fix the damage. This filler is so strong that it can withstand being sanded with an industrial-strength electric sander without breaking.
What is a wood hardener? When should you use it?
Unlike other wood treatments, wood hardener improves the wood’s strength without masking its natural grain. The wood hardener is applied directly to the affected area.
Then it penetrates deep into the wood fibers, binding with the cellulose to create a solid and durable surface. You can use it to smooth out rotting or damaged wood, making it suitable for filling.
How do interior and exterior wood fillers differ?
Wood filler inside a building is not the same as intended for outside. The exterior fillers dry far more durable than the interior fillers, so they can withstand severe weather.
Fillers made for the environment outside accelerate the drying process, so external fillers harden considerably more quickly.
My Top Pick For an Exterior Wood Filler: Bondo Home Solutions 20082
After all the experiments and tests I’ve done, I’ve landed on a favorite: the Bondo Home Solutions 20082. Its strength and adaptability for both indoor and outdoor wooden surfaces genuinely set it apart. One impressive feature I’ve personally noticed is how it hardens even better as the temperature climbs. So, if you’re looking for the best exterior wood filler, I’d highly recommend giving this one a shot.
Robert Johnson is a passionate furniture maker & carpenter, sought after for his knowledge on the craft.
You’ve probably seen his down-to-earth wisdom in USA Today, Bobvila, Family Handyman, and The Spruce, where he has shared commentary and guidance on various woodworking topics.
Robert is the brain behind Sawinery, where he aims to share tips, tricks, and a passion for all things carpentry.
