Filling Holes and Gaps – Do I use caulk, wood filler, or spackle?
Trying to decide between spackle vs caulk and wood filler vs caulk for filling holes and gaps in your DIY projects? This beginner's guide walks you through caulk, wood filler, wood putty, spackle, and joint compound. Learn how to choose the right product with confidence!
Thank you to DAP for sponsoring this guide on caulk, wood filler, and spackle! All opinions are entirely my own. This post also contains affiliate links, but nothing that I wouldn’t recommend wholeheartedly. Read my full disclosure here.
There are so many different kinds of materials to fill holes and gaps in your DIY projects and around your house. Caulk, wood filler, wood putty, spackle, joint compound…just to name a few.
It’s no wonder that most DIYers and homeowners are pretty confused about what the best product is.
Whether you are filling gaps in trim and baseboards or filling nail holes, there are a lot of final finishing touches needed when you’re working on weekend DIY home projects, renovations, and woodworking projects.
Caulk Overview
Caulk or caulking is a material used to fill gaps in the seams between two materials or to seal joints. It is sold in a tube that is loaded into a caulking gun, which is used to push out the caulking into the seam. It is also sold in a squeeze tube.
Caulk is used both to make seams, joints, and corners sealed off from water, bugs, air, and/or water.
Caulk is usually made of either latex or silicone (or a combination of the two).
There are tons of different types of caulk for all sorts of renovation and construction uses, so it’s very important that you’re choosing the right caulk for the job.
What is caulk used for?
- Flexible exterior caulk is used around windows, doors, siding, and around the trim
- Flexible interior caulk is used around trim and baseboards, on the corners and edges of accent walls (like shiplap)
- Interior caulk for kitchens and bathrooms (or anywhere that may get wet or exposed to moisture) is used for all joints, corners, and gaps between two materials. For instance, where sinks meet countertops, where tile meets countertops on backsplashes, where a bathtub or shower meets the wall or floor, etc.
Learn more about the different caulk types and how to apply them!
What’s the best caulk?
Alex Flex Caulk
For interior applications for trim and molding, we love DAP’s Alex Flex Premium Molding & Trim Acrylic Latex Siliconized Sealant.
It is a high-performance sealant specifically formulated for use in molding and trim applications. It delivers excellent adhesion and flexibility for a crack-proof seal. We also love that it is ready to paint within 30 minutes.
Extreme Stretch Caulk
If the caulking is needed in an area that will undergo an extreme change in temperature or possible movement, another great option is DAP’s Extreme Stretch Acrylic Urethane Premium Elastomeric Sealant.
It is a high-quality caulk that is ideal for sealing a wide variety of interior & exterior surfaces. It is specially formulated to stretch over 600% ensuring the seal does not crack or lose adhesion making it perfect for most sealing projects including windows, doors, trim, siding, corner joints, sinks, and countertops.
Kwik Seal Ultra Caulk
For sealing in the kitchen and bathrooms, we love DAP’s Kwik Seal Ultra Advanced Kitchen & Bath Sealant.
It is an advanced sealant formulated with innovative ultra-hydrophobic technology that repels water, dirt, and stains and offers a lifetime mold and mildew resistance guarantee so the sealant stays looking clean, fresh, and new.
Can you use caulk to fill nail holes?
When you’re handling things like trim, you’ll come across both nail holes and gaps between the trim and wall. Chances are that you’ll be tempted to just fill nail holes with caulk while you have it out. Why not hit two birds with one stone, right?
We do not recommend using caulk to fill nail holes.
The downside of using caulk to fill nail holes is that caulk is not sandable, so you can get it as smooth as wood filler or spackle. Caulk is also fairly messy, so it’s a risk to use caulk to fill a small nail hole.
Lastly, caulk is more likely to shrink over time rather than wood filler or spackle.
Wood Filler Overview
Wood filler is a sandable material that can be applied to nail holes, gouges, cracks, gaps, and imperfections on the wood surface.
Typically wood filler is used once a project is built, but not yet stained/painted/sealed. Filling nail holes and other imperfections is one of the final steps in your woodworking projects.
Once applied and dried, you can sand it smooth and stain or paint your project.
What is wood filler used for?
- Filling nail holes in woodworking projects
- Filling gouges and imperfections in the wood
- Filling dents, gouges, and nail holes in wood trim and baseboards (that has not been stained or sealed yet)
- Smoothing cracks in wood projects
- Smoothing joints (where two pieces of wood come together)
- Shape damaged areas, like corners and edges
What is the best wood filler?
Plastic Wood X All Purpose Wood Filler
For filling nail holes, gouges, cracks, and imperfections in the woodworking projects we typically use DAP’s Plastic Wood X™ All Purpose Wood Filler with DryDex Dry Time Indicator.
One thing I love about it is that it goes on pink and dries to a natural, wood finish, so you know when it’s ready to sand! How cool is that? This patented technology eliminates the guesswork of trying to figure out when to sand and reduces the chance of errors.
The wood filler is ready-to-use and has a thick knife-grade formula that spreads easily for fast, professional repairs and can even be applied on vertical surfaces.
Plastic Wood X is stainable, paintable, and won’t shrink crack, or crumble. It can be sanded, planed, cut, drilled, screwed, or nailed once cured.
Premium Wood Filler
DAP’s Premium Wood Filler is a custom 3-in-1 wood filler, grain filler, and sealer coat. It has a unique water-based formula that allows you to more accurately match existing wood tones to create a repair that is seamless and invisible.
The Premium Wood Filler won’t sink, shrink, crack or fall out. It has strong impact resistance making it perfect for edge or crack filling. It dries fast (a little faster than Plastic Wood X), which allows you to finish your woodworking project faster.
The Premium Wood Filler has Chameleon Color Blend Technology allows you to mix stains or pigments directly into the wet state for an exact color match. Alternatively, you can also apply the stain afterward because this wood filler accepts stains, tints, pigments, dyes, and finishes.
If you want to use it as a grain filler (like if you’re painting the wood surface and don’t want to be able to see the wood grain texture through the paint) you can thin it slightly with warm water until you get to a thick paint-like consistency. Then brush it across the wood grain to fill the natural wood pores. This will provide a smooth, tabletop finish.
How To Use Wood Filler
- Clean the surface. The area that needs filling should be clean – dry and free of dirt and sanding dust. The surface and air need to be above 40 degrees F.
- Apply wood filler. Use a clean putty knife to push wood filler into larger gouges and lightly scrape the knife flat over the surface to smooth out. For small nail holes, you can simply use your finger to press the filler into the hole. You want to overfill the repair slightly when applying the wood filler so you can sand it down to a smooth, flat finish once dry.
- If the damaged area is deeper than 1/8″ – 1/4″, apply the wood filler in layers and let each layer dry before moving on.
- Sand smooth. Once the wood filler is dried (when it is no longer pink if using Plastic Wood X with DryDex), you can sand smooth using 150 grit sandpaper. It should take approximately 2-6 hours for shallow repairs to dry and up to 36 hours for deeper fills.
- Stain or paint. Once sanded, typically you can stain or paint over the wood filler as needed. Be sure to check the label for specific instructions so you can achieve the best finish possible.
Should I use wood filler or caulk?
To sum up the difference between caulk and wood filler, caulk is to be used to fill in corners and gaps between two materials, whereas wood filler should be used to fill nail holes and other damage on flat wooden surfaces.
Wood filler can be sanded and caulking can not.
Wood Putty Overview
Wood putty is a malleable material that is used to fill small holes and damage in woodworking and furniture. Wood putty is generally applied after the project has been completed (meaning stained, painted, and sealed).
Another use of wood putty could be treating damage on older wooden furniture or molding. Even if the piece has been sealed for years, you can find a good color match and fill the damage with wood putty.
One key feature of wood putty is that it does not harden once dried. It remains malleable over time, meaning that you cannot sand it smooth.
Plastic Wood Putty (Non-Hardening)
DAP’s Plastic Wood Putty is an easy-to-use, non-hardening wood putty that is ideal for filling small holes and minor defects in interior wood surfaces (like stained baseboards) after assembly and finishing.
It is recommended for filling and hiding countersunk nail holes, gouges, scratches, and miter joints.
Plastic Wood Putty is available in 12 popular wood tones to match most finished wood surfaces. The colors can be blended together for custom color matching.
What is the difference between wood filler and wood putty?
The key difference between wood filler and wood putty is that wood filler hardens once dried (so it can be sanded smooth) and wood putty does not.
Wood Filler can be used on interior and exterior applications (at least the products I mentioned above), whereas wood putty can be used on interior projects only.
Lastly, wood filler is meant to be used during the building process before the piece has been stained/sealed, or painted. On the other hand, wood putty is intended to be applied after the piece has been finished.
Spackle Overview
Spackle is a soft substance that is used to repair small damaged areas in drywall (like small holes, dings, and dents) and fill nail holes on walls. Spackle is typically made from gypsum plaster, glue, and other compounds.
Spackle is definitely one of those must-haves for homeowners to always keep around, especially if you’re going to be doing any interior painting.
What is spackle used for?
- Filling nail holes on the wall before painting
- Smoothing dents and dings in walls before painting a room
- Filling dents, joints, and nail holes in pre-painted or primed trim and baseboards before painting
- Filling nail holes and any imperfections on a door frame or window trim (although check your label first because some spackling is not made for door and window frames)
- Patching nail holes on accent walls, like board and batten and faux shiplap
- Repairing a small crack in drywall
Spackle is used before painting a room to repair damage to the walls, like nail holes and dents and dings.
What is the best type of spackle?
DAP makes several different spackling products that fit different uses, jobs, and budgets. Here are 4 of our favorites!
DryDex Spackling
DAP’s DryDex Spackling is America’s #1 seller and generally where we turn first when we are filling holes before painting. DryDex Spackling shouldn’t shrink or crack after being applied.
Just like Plastic Wood X wood filler, it contains a patented DryDex Dry Time Indicator causing the product to change color when optimum dry time is achieved, which is generally 1 to 5 hours. It goes on pink and turns white when dry! This unique feature is the indicator that it is ready to sand and paint.
Alex Flex Flexible Spackle
If the area you’re patching has a tendency to crack and you’ve experienced reoccurring cracks in drywall, you should go with DAP’s Alex Flex Flexible Spackling. It is similar to DryDex spackle, in that it won’t shrink or crack and is sandable and paintable – but it is more flexible.
Fast Dry Premium Spackling
If you’re in a hurry and don’t want to wait for 1 to 5 hours for the spackle to fully dry before sanding and painting, you can use DAP’s Fast Dry Premium Spackling. It has an 8x faster dry time when compared to traditional heavyweight spackling and is usually ready to paint in just 15 minutes.
Alex Plus Spackling
DAP’s Alex Plus Spackling is another great option for filling holes & cracks in surfaces such as drywall, plaster, wood, brick, metal, and stone. It has a ready-to-use, smooth white formula that spreads easily for fast, professional repairs that will not sink, shrink or crack.
How To Use Spackle
- Clean the surface. The area that needs patching should be clean – dry and free of dirt and dust. If you need to learn more about how to clean walls before painting, check out this tutorial.
- Apply spackle. Stir up spackle using a putty knife. Use a clean putty knife to push spackle into holes and damaged areas, then lightly scrape the knife flat over the surface to smooth out. For small nail holes, you can simply use your finger to press the spackle into the hole. You want to overfill the repair slightly when applying the spackling so you can sand it down to a smooth, flat finish once dry.
- To get better adhesion to your surface, lightly sand the surface first with a sanding block to d-gloss the surface.
- If the damaged area is deeper than 1/8″ – 1/4″, apply the spackle in layers and let each layer dry before moving on.
- Sand smooth. Once the spackling is dried (when it is no longer pink if using DryDex), you can sand smooth using a sanding block. Dry time is generally 1-5 hours. You can always touch the surface to see if it is dry and if your sandpaper becomes clogged with spackling, wait and let the repair dry longer before sanding to a smooth finish.
- If you’re in a hurry, try Fast Dry Spackling for a 15 min paint-ready dry time.
- For a smoother finish, dip your putty knife into water and lightly smooth spackling prior to drying.
- Paint. Once sanded, you can paint the surface.
What’s the difference between spackle and wood filler?
The difference between spackle and wood filler may be hard to tell because they both fill holes on flat surfaces before painting and they are both sandable.
But the key difference between spackle and wood filler is that spackle is not stainable like wood filler is. So if you are planning to stain your project – wood filler is definitely the right choice.
Going further, wood filler and spackle are made a lot differently – even though they do some of the same things (like fill holes).
Wood filler is designed to cling and stick to wood, whereas spackle is made to adhere to drywall, stone, and plaster. This is one reason why you should stick to wood filler for wood and spackle for walls.
Can you use spackle as wood filler?
One of the big questions you’re probably wondering is “can you use spackle as wood filler?” The answer is technically yes, it will usually “do the job”. If you’re in a pinch and that’s all you have and you only need to fill one small hole – sure, go ahead. However, wood filler is generally the better option when you’re working directly with raw wood.
What’s the difference between spackle vs caulk?
To sum up the difference between spackle vs caulk, caulk is to be used to fill in corners and gaps between two materials, whereas spackle should be used to fill nail holes and other damage on flat surfaces (walls and/or trim).
Spackle can be sanded and caulk cannot.
Joint Compound Overview
Joint Compound (also called drywall mud or mud) is a wet substance that is applied over the top of drywall to seal joints and create texture and a base for painting on interior walls and ceilings.
Joint compound is usually made with gypsum dust, water, and other ingredients. Sometimes it is sold as a dry powder that gets mixed with water and other products sell it as a pre-mixed material.
Is spackle the same as joint compound?
Although spackle and joint compound have similar jobs, they are very different. Joint compound is much runnier than spackle and, therefore, dries much slower than spackle (24 hours for joint compound vs 1-5 hours for spackle).
Joint compound should be used when texturing drywall or repairing large areas of damaged drywall. Spackle is best used for filling smaller holes and damage in drywall.
Joint compound definitely needs to be primed before painting, whereas many high-quality spackling products can be painted without priming first.
What’s the best filler for the job?
We’ve covered a lot in this guide for filling holes and gaps, so we thought we would sum it up with a list of basically everything job you will find in renovations and DIY projects and end the debate on what product to use. No more wondering about spackle vs caulk or wood filler vs caulk!
Below you’ll find a list of every product (caulk, wood filler, wood putty, and spackle) that we mentioned in the guide and a short bullet-point list of what to use the product on.
Alex Flex Caulk
- Filling gaps in trim (ie: board and batten walls)
- On the corners and edges of accent walls (ie: shiplap walls)
- Filling gaps between wall and baseboards
- Filling gaps between wall and door frame
- Filling gaps between wall and window frame
- Filling gaps between wall and moldings (ie: crown molding, picture rail, chair rail)
Kwik Seal Ultra Caulk (kitchen & bath)
- Filling gaps between tile backsplash and countertop
- Sealing all joints and corners in a shower (When caulking in a shower, you want to add it where the bathtub meets the tile wall, where the bathtub meets the tile flooring, all corners of the shower, along the ceiling corner, and in all corners of the shower niche).
- Base of the bathtub where it meets the flooring
- Any edges of trim or walls that butt up against a shower or bath
- Filling gaps between sink and countertop
- Filling gaps between wall and countertop
Plastic Wood X Wood Filler
- Filling nail holes in woodworking projects
- Filling gaps between two pieces of wood in a woodworking project
- Patching nail holes in wood trim and baseboards
- Filling gouges or imperfections in the wood
Premium Wood Filler
- Filling nail holes in woodworking projects (before staining or painting)
- Filling gaps between two pieces of wood in a woodworking project
- Filling gouges or imperfections in the wood
- Filling grain on wood before painting
- Smoothing cracks in wood
- Shaping damaged areas, like corners and edges
- Interior or exterior use
Plastic Wood Putty
- Filling nail holes, gouges, dents, and cracks on woodworking projects (after finishing)
- Repair damage to older wooden furniture or molding
- Interior use only
DryDex Spackle
- Filling nail holes on the wall before painting
- Smoothing dents and dings in walls before painting a room
- Filling dents, joints, and nail holes in pre-painted or pre-primed trim and baseboards before painting
- Filling nail holes and any imperfections on a door frame or window trim
- Patching nail holes on accent walls, like board and batten and faux shiplap
- Repairing a small crack in drywall
Alex Flex Flexible Spackling
- Everything mentioned on DryDex Spackling (above)
- Repairing reoccurring cracks in drywall
Fast Dry Premium Spackling
- Everything mentioned on DryDex Spackling (above)
- When you’re in a hurry and don’t want to wait 1-5 hours for the spackle to dry
Alex Plus Spackling
- Everything mentioned on DryDex Spackling (above)
There are so many different products out there for filling holes and gaps in your DIY project, it’s easy to be confused. Hopefully, by using this guide, you now know if you should use wood filler vs caulk or spackle vs caulk on your next project.
You can confidently head to the hardware store and purchase your supplies knowing that you’re buying the best filler material for your project!
Do you have any other questions about filling holes and gaps in your projects?
Let us know in the comments below!
I have faux brick wall panelling in the guest room that I want to do a whitewash or “german schmear” technique on. Which product would I use, spackle or joint compound and how would I seal it so it would not rub off on bedding and clothing.
Thanks!
By the way, this is an incredible resource! Thank you so much!
Hi Alicia, thanks for your note! German schmear on faux brick wall panels is such a fun project. We have a full tutorial here: https://www.makingmanzanita.com/german-schmear-faux-brick-wall/
We used joint compound on ours, but spackle would work well too. You want to seal it once dry with a watered down white paint (that’s what we did) or a clear coat sealer that will not yellow (like Polycrylic)
Years ago I used spackling compound to fill cracks and holes in dry wall, but instead of sanding I sponged it smooth before it dried. I know professionals don’t do this but it worked beautifully for me for holes and thin cracks. Now there are so many types of spackling compound, I’m wondering which type would be best to use if I want sponge it?
Joint compound is probably what you are remembering, joint compound (aka drywall mud) will wipe smooth with a wet sponge. Spackling is a little different and doesn’t work quite the same and typically requires sanding to smooth. If you want to sponge it, joint compound is your best bet.
I bought a used pre-painted wood cabinet at a consignment shop that is in great condition, BUT the manufacturer “distressed” the wood before painting so that there are a lot of small holes and gouges. How can I properly fill these holes so that the holes either aren’t visible, or are greatly diminished so that I can paint over the whole cabinet and get a relatively smooth finish? Spackle? Wood Filler? Wood Putty?
I would greatly appreciate your input so that I can finish my project. Thank you.
For this purpose, I would recommend wood filler. The DAP Plastic Wood X product that I mentioned in the article should be perfect.
With wood projects to be painted do you find it best to fill nail holes and minor imperfections and caulk before priming or after priming?
Great question. For painted wood projects, we do all filling and caulking before priming. Be sure the products you are using are paintable 🙂
Hey! Thank you for all of this information! I am scraping popcorn ceilings and am noticing gaps between ceiling and walls. Should I caulk the space or use spackle? I’m leaning to spackle since it’s drywall but not for certain since it is like a corner (just all the way around the room). Thanks for the input!
Assuming the gap is small here (Bigger than 1/4″ and you’ve got an issue). In the corners of a room, I would recommend a flexible caulk. That way it will be less likely to crack in the future.
Thanks for the helpful tips.
Not sure if you live in Manzanita, Oregon
But it is beautiful there.
You’re welcome! No we’re in Central Oregon – not Manzanita, but we totally need to go check it out. I’ve heard great things.
You’re welcome! No we’re in Central Oregon – not Manzanita, but we totally need to go check it out. I’ve heard great things.
Basement stairs, bad wood, some raw, some painted, etc. plus nail holes and old nailed in carpet tacks. Want to prime and paint, but want to fill rough cracks and seams before doing so. Hardware store recommended spackle as cheaper option since so much to do (sides of risers, stair treads, knots on landing) and it is stairs to mostly unfinished basement. I’m concerned spackle might crack up on stairs…. Your advice? You think spackle would work on this application? Thanks.
Hard to know exactly without seeing the damage firsthand, but based on this explanation I would probably recommend the Alex Flex Flexible Spackling, which I linked above. It has a little more give and take than traditional spackle to prevent cracking on joints that have some movement, like stairs.
I want to paint the hardwood floor in my kitchen. I’m going with a shabby cottage look. I was thinking about filling some of the spaces between some of the boards to give them the appearance of wide planks of different widths once painted.
I can’t figure out which product would be best suited for this project. Any suggestion are appreciated!