They’re both white. They’re both thick and pasty. They both go on walls. So what’s the difference between joint compound vs. spackle? The truth is, despite appearances, there are significant differences between these two. You want to use joint compound if you need to fix cracks and/or large holes. Additionally, it is used to cover the seams of two pieces of drywall. You want to use spackle for smaller jobs, this includes minor blemishes, nail holes, etc.
These differences dictate how and when you might use joint compound vs. spackle. Using the right tool for the job can mean a job well done. The wrong tool could mean a job to do over or scrap altogether. So, to ensure you know which tool is the right tool, let’s dive into these two substances.
Table of Contents
Joint Compound Overview
Joint compound is also known as “mud” because it’s about the same consistency. You could stand a stick up in it but still pull the stick out easily. When you mix joint compound, you know you have the right consistency if it’s spreadable like cream cheese.
Joint compound is water, limestone, perlite, polymers, and a few additives. Some joint compounds come as a powder, and you can add water and mix it yourself. However, most are sold premixed.
Types of Joint Compound
- Drying Type: It comes ready to use and air dries over a long period. It’s prone to shrinking and cracking as it dries.
- Setting Type: You should mix it right before use. It uses a chemical reaction to set quickly. Because the reaction produces heat, this kind is also known as “hot mud.”
- All-Purpose Compound: This is premixed and can be used for any layer in the drywall process. It’s not as easy to sand and shrinks more.
- Special joint compounds: These exist for fireproof drywall, low-dust drywall, and mold resistance.
You might be thinking, “that’s nice, but what do I use joint compound for?” All of the above types of joint compound are used to smooth the surface of drywall just before painting. You can also use it to create textures on a wall. If you’re not familiar with drywall, check out this article.
The compound is used with drywall tape. You put the tape on the seams where two pieces of drywall meet. Then, you cover it with joint compound. It’s also used to cover any nail holes or blemishes, so there’s a smooth surface ready for the first coat of paint or primer.
When you buy joint compound, you purchase several pounds at once. It can come premixed in a bucket or as a powder in a bag. Either way, you’ll still need to do some preparation before using it. Make sure you have a rag, water, a mud paddle, and a taping knife handy. If you use the setting type of joint compound, don’t mix a lot at once. It dries quickly!
Artists sometimes use joint compound to make a textured canvas. They create the bumps and ridges they want and then paint a picture on top of it. Using the drying type gives the artist time to change textures. Once it’s dry, it provides a durable underlayer.
Spackle Overview
When you get a cut or a scrape, what do you put on it? If you said “Band-Aid,” you used a brand name of adhesive bandage. It’s the same if you blow your nose with a “Kleenex” instead of facial tissue. They’re both examples of a genericized trademark when we use a brand name to describe all brands of the same product.
Spackle is no different. It’s a product trademarked by the New Jersey company, Muralo. Technically, all other similar pastes used to fill holes are called “spackling paste.” However, the brand is so popular that now we call all the pastes “spackle.”
Spackle or spackling pastes are made from gypsum powder and glue. Some include dyes made to match wood or other surfaces. You can use spackle on drywall, wood, and plaster. It, too, comes in several varieties.
Types of Spackle
- Standard spackle: This is useful for patching most cracks and holes. It is easy to sand down to a smooth finish.
- Lightweight spackle: It’s used for light scratches and minor blemishes. It can crumble, so it’s best for low-traffic areas.
- Acrylic spackle: It is water-based and used on brick and stone. It’s more flexible than standard spackle, so it doesn’t shrink as it dries. It can’t withstand freezing temperatures while it’s drying.
- Vinyl spackle: This is water-based and used on shallow grooves and scratches. It should be applied in thin layers and allowed to dry between applications. Vinyl also doesn’t tolerate being frozen before it’s dry.
- Epoxy spackle: This one is oil-based and has to be mixed before use. After you combine the two chemicals, it forms a moldable putty. When it dries, it holds its shape and is easy to sand down.
Spackle is useful for repairs. You can use it to fill nail holes, dents, and scratches in walls like this. It doesn’t have any load-bearing capacity, so don’t expect it to hold anything up or together. Like drywall compound, it helps prepare a smooth surface, so paint goes on looking good.
Main Differences Between Joint Compound vs. Spackle
We’ve covered how the two are similar – texture, color, application. Now, let’s look at what sets joint compound and spackle apart from each other.
The first difference is what’s in them. Joint compound gets its strength from limestone and expanded perlite. Limestone is a rock, it is mostly calcium carbonate left behind by ancient shells. Perlite is a volcanic glass. The manufacturer heats it until it expands.
Spackle is mostly gypsum. Gypsum is a sulfate mineral people use it to make plaster of Paris and cement. On its own, it’s not an especially strong mineral. But mixed with adhesives, it can harden enough to be sanded down.
The second difference is their primary uses. Joint compound is used in construction to finish off drywall or repair plaster. It’s part of the process for building interior walls. It comes in large buckets and bags weighing several pounds. If you’re sitting in a room right now, chances are there’s joint compound under the paint right next to you.
Builders don’t use spackle as part of wall construction, they use it for repairs. It comes in small, pint-sized containers you can buy to use at home. People use it to patch nail holes in apartments to avoid losing their security deposit. It functions as a cosmetic tool, not a structural one. You might or might not paint over it.
Can You Substitute Joint Compound for Spackle?
Say you’re moving a piece of furniture and accidentally put a dent in your living room wall. You’re trying to fix the dent but don’t have any spackle on hand. Can you use joint compound instead? Yes, you can! Just take a little bit of it and use a palette knife to press it into the hole. Smooth the surface, and you’re good to go.
Can you Substitute Spackle for Joint Compound?
So you’re finishing your basement and putting up sheets of drywall. All the drywall is securely in place, and it’s time to fill the gaps in the joints. Can you take out your tub of spackle and use it to do the job? No, you can’t! Spackle isn’t for covering large areas. It may crack, shrink, or crumble if applied in large patches.
Top Picks – Joint Compound and Spackle
Now that we’ve nailed down the difference between joint compound and spackle, let’s shop around and see some buying options. Here are two great examples from each category so you can make an informed choice when it comes time for some DIY home repair.
Spackle
Since spackle is sold in small quantities, manufacturers like to pair it with a simple tool that helps the job go more smoothly. A spatula or palette knife is necessary for smoothing the surface after you apply spackle. You may also need a wet rag and sandpaper.
Soto Spackle + Paint Repair Nail Hole Filler
Spackle that comes in tubes is usually less messy to use than the kind in the tub. Instead of scooping and scraping, you can squeeze the spackle into the hole you want to fill. Then, use the tool to scrape the excess away.
This repair kit comes with a 4-ounce tube of spackle and a wood-handled metal putty knife. You can find it in white, beige, and four colors in between. Because it’s so smooth, you don’t even have to sand it down before you’re done.
What’s Good
- Durable, so you don’t have to stop in the middle of a job to buy a new one
- Different available colors so you may not need to paint over it to match your wall
- Non-toxic, so you don’t have to worry about kids or pets getting ahold of it
- Only takes a few minutes to dry, and you can paint over it or touch it soon after you use it
What’s Not So Good
- Tube only comes in a 4-ounce size, which may not be enough for large jobs
- Colors don’t look the same on different devices so you can’t always tell if it’s going to match
Joint Compound
Since joint compound is a building tool, not necessarily a repair tool, you’ll probably need a lot more of it than you would with spackle. Expect to find premixed joint compound sold in large quantities, several pounds to a package. The same goes for the dry compound.
Even with the premixed “mud,” you need to have a mixer of some kind so you can add water. It’s almost always too thick to use right out of the package. The best tool for this is a drill with a paddle attachment. You can also use a “mud masher,” a tool that looks like a potato masher.
US Gypsum All Purpose
US Gypsum makes a lot of different products for construction projects. You’ll even see their brand, Sheetrock, used on commercial construction sites and professional home repair jobs. They don’t waste time on pretty packaging or kitschy gimmicks. Their products just work.
This one-gallon bucket is enough for 18 square feet of drywall, plus a little extra for patching over nails. You can use it to create textures on top of the final tape or use it with the drywall tape layer. You can use joint compound on ceilings as long as you don’t mix it too thin.
What’s Good
- Premixed, making it less work and less messy than the dry compounds
- Nice and thick composition, although you can make it thinner
- Bucket has a handle for easy carrying (You’d think this would be a standard feature, but a lot of brands don’t come with a handle)
- One thin coat is opaque, and you don’t much compound if you’re using it to cover marks or printing on the drywall
What’s Not So Good
- Doesn’t sand down as smoothly as other options, meaning it could require a few passes with different paper grades
- Compound needs around 24 hours to dry completely, so it’s not ideal if you’re in a rush
Joint Compound vs. Spackle Summary
To recap what we’ve covered in our comparison, here’s a handy cheat sheet:
- Joint compound contains limestone and perlite.
- Spackle contains gypsum and glues.
- Use spackle for small repairs.
- Use joint compound for finishing drywall.
- You can use joint compound as spackle.
- You cannot use spackle instead of joint compound.
A helpful way to remember what each is useful for is to compare the sizes they come in. Joint compound comes in buckets of a pound or more. You’ll need a lot of it to cover drywall joints. Spackle comes in small tubes. You only need a little bit to patch gouges, holes, and cracks.
The only thing we haven’t touched on here is safety. In general, a powdered product presents more of a health concern than a paste. However, when you sand a paste, you get airborne particles that can be inhaled. Wear a mask and follow these CDC guidelines to control dust.
