How To Caulk A Bathtub

When it comes to maintaining the appearance and functionality of your bathroom, one of the most important tasks you can do is to regularly caulk your bathtub. Caulking is the process of sealing the gaps and joints between your bathtub and the surrounding walls or tiles. This helps to prevent water from seeping behind the bathtub, which can cause damage and eventually lead to mold and mildew growth. In this article, we’ll cover everything you need to know about how to caulk a bathtub.

What You’ll Need

Before you begin, it’s important to gather all the necessary tools and materials. Here’s what you’ll need to caulk a bathtub:

  • Caulking gun
  • Caulk
  • Caulk smoothing tool
  • Clean cloth or sponge
  • Cleaner or rubbing alcohol
  • Masking tape (optional)

Preparing the Surface

The first step in caulking a bathtub is to prepare the surface. This involves removing any old caulk or sealant, as well as cleaning the area thoroughly. To do this, use a caulk softener or scraper to remove the old caulk. Then, use a cleaner or rubbing alcohol to wipe down the area and remove any dirt, debris, or soap residue. If necessary, you can also use masking tape to protect the surrounding tiles or walls.

Applying the Caulk

Once the surface is clean and dry, it’s time to apply the caulk. Load the caulk into the caulk gun, and starting at one end of the bathtub, apply a steady, even bead of caulk along the joint. Be sure to apply enough caulk to fill the gap completely, but not so much that it overflows. Move along the joint, applying caulk as needed, until you reach the other end.

Smoothing the Caulk

After you’ve applied the caulk, use a caulk smoothing tool to smooth out the bead and ensure that it’s evenly distributed. Hold the tool at a 45-degree angle and run it along the joint, applying steady pressure. This will help to spread the caulk evenly and create a smooth finish.

Cleaning Up

Once you’ve smoothed the caulk, it’s time to clean up any excess or stray caulk. Use a clean cloth or sponge to wipe away any excess caulk, being careful not to disturb the newly applied bead. You can also use a damp cloth or sponge to smooth out any rough spots or ridges.

Drying and Curing

After you’ve finished applying and smoothing the caulk, it’s important to let it dry and cure properly. This can take anywhere from 24 to 48 hours, depending on the type of caulk you’re using and the humidity and temperature of your bathroom. During this time, it’s important to avoid using the bathtub or getting it wet, as this can compromise the seal and cause the caulk to fail.


How often do I need to caulk my bathtub?

You should plan to caulk your bathtub at least once a year, or whenever you notice gaps or cracks in the existing caulk.

What type of caulk should I use?

For most bathtub caulking jobs, a silicone-based caulk is best. This type of caulk is waterproof, flexible, and durable, making it ideal for use in a damp environment like a bathroom.

Can I caulk over existing caulk?

While it’s possible to caulk over existing caulk, it’s not recommended. Over time, the layers of caulk can build up and become brittle, which can compromise the seal and lead to leaks or water damage.

How long does caulk last?

With proper installation and care, caulk can last up to 10 years or more. However, it’s important to inspect your caulk regularly and reapply as needed to ensure that it’s doing its job properly.


Caulking a bathtub may seem like a daunting task, but with the right tools and techniques, it can be a simple and straightforward process. By following the steps outlined in this article and using the tips and tricks we’ve provided, you can ensure that your bathtub is sealed properly and protected from water damage. So, grab your caulk gun and get to work – your bathroom will thank you!