How to use a caulk gun in 6 easy steps

• Caulk guns make it easy to create a waterproof seal around sinks, windows, tubs, and more.
• Make sure you are using the right type of caulk for the job - like silicone caulk for bathrooms.
• Caulk guns dispense the product neatly and without waste.

Caulk is a waterproof sealant used to fill in cracks and gaps around sinks, tubs, windows, counters, and more in your home. Depending on the type of caulk you use, you can also use it outdoors to seal siding, concrete, and masonry.

Using a caulk gun might seem intimidating if you are inexperienced with home improvement. You might have visions of spewing sealant over everything but the actual opening you are trying to seal. But a caulk gun is quite simple to load and use.

"Caulking guns have evolved over the years," says George Esposito, owner of Canal Kitchens in Staten Island, NY. He notes that with older models, unless you remember to pull back on the rod, the caulk will continue to flow. "[Manufacturers] make guns today that when you release the trigger, the plunger automatically backs up and will not force the product to ooze out," he says.

Because a caulking tool is so easy to use, applying caulk is an easy DIY project for beginners and just requires the right type of caulk, an inexpensive caulking gun, and a little practice.

What you need

• Canister of caulk
• Caulk gun
• Caulk removal tool, such as a putty knife or utility knife
• Household cleaner or rubbing alcohol
• Cloth
• Mineral spirits (for cleanup of some caulks only)
  
  

Optional:

• Painter's tape
• Caulk softener
• A tool for smoothing
• Needle-nose pliers

How to use a caulking gun

1. Prep your workspace. Remove all existing caulk with a putty or utility knife. For silicone caulk removal, needle nose pliers are also useful-simply grab one edge of the old caulk strip and pull. If the caulk is very old or there are multiple layers, you can use a caulk softener for easier removal.
   
   Once all caulk is removed, clean the area with a household disinfectant or rubbing alcohol, then dry it with a cloth. If you prefer, you can mark the edges of the joint with painter's tape for easier cleanup.
2. Load the caulk gun. Trim the tip of the caulk canister with a utility knife; some caulk guns have a cutter in the handle to snip the tip off. Puncture the foil inside the nozzle using a nail. On some guns, there may be a pin attached to the handle for this purpose.
   
   Next, insert the canister so that the tip is facing out. Push the rod into the canister until it is securely in place. Pump the trigger until the caulk starts to come out.
3. Practice laying the bead. The line of caulk is known as the bead. If you're a first-timer, practice on a piece of paper so you can understand how the caulk will flow as you pull the trigger. Practice laying down the bead at a speed that's not too fast or too slow, so you can control the flow of the caulk.
4. Apply the caulk. Once you're comfortable, place the tip of the canister at a 45-degree angle on one end of the joint or gap. Pull the gun back steadily as you squeeze the trigger. Some types of caulk shrink as they dry (cure), so be sure to apply enough to fill the joint.
5. Smooth the caulk. Run a flat tool (the back of a spoon works) or even a wet fingertip along the bead to push it into the joint and smooth it out - this is known as tooling. Esposito says to finish tooling before the caulk "skins" over, meaning it loses its bonding ability and becomes difficult to work with.
   
   Wipe off any excess - some caulks require just water while others need a solvent. If you applied painter's tape, remove it now so the caulk dries neatly. It might be dry to the touch in 30 minutes, but caulk could take several days to fully cure.
6. Store the unused caulk. When stored properly, opened caulk can last for months. Simply remove the canister from the gun and cap it securely. The release lever on the back of the caulk gun will reverse the plunger so you won't squeeze out any excess caulk upon removal, says Esposito.

How to choose the right type of caulk

• Rubber (butyl) caulk: Appropriate for outdoor use as filler for asphalt, aluminum gutters, and roof flashing. To clean up excess, use mineral spirits, an inexpensive, petroleum-based material that works as a paint thinner. Note: The solvents in rubber caulk are highly toxic and flammable, so do not use them indoors.
• Latex caulk (including vinyl latex and acrylic latex, also known as painter's caulk): Good for just about all interior sealing needs and some exterior applications, like siding and trim. It's easy to use and needs only a wet rag for cleanup. Latex caulk comes in a variety of colors to match the connecting materials. It can also be painted.
• Silicone caulk: Best for sinks, tubs, and showers, as well as a home's exterior and aluminum gutters. It's also good for use on glass and other nonporous materials. Only water-based silicone can be painted, and cleanup requires use of mineral spirits.
• Polyurethane sealant: Ideal for use on windows, vinyl siding, concrete, and masonry. It is stronger than silicone, resists shrinking, and can be painted or stained. It can be difficult to apply, though, and mineral spirits or a solvent is required for cleanup.

Quick tip: If you have a very small or awkwardly placed spot that needs to be caulked, caulk also comes in squeeze tubes and ready-to-use strips. However, a caulk gun makes for a much smoother application with less shrinkage.

Insider's takeaway

It's easy to get a handle for using a caulk gun. Sealing up joints, cracks, or other gaps in your home can certainly be a DIY project even for a beginner, provided you use the correct type of caulk. If you are unsure, talk to an associate at the hardware store about the nature of your project so you can purchase the right sealant for the job.