How To Make Non-Paintable Caulk Paintable

Silicone caulk is one of the most durable caulks; it’s water-resistant and commonly used in bathrooms and around sink fixtures. Unfortunately, this material is non-paintable. If you want to paint existing caulk to improve the look of your house’s interior, there are a few steps to follow.

To make non-paintable caulk paintable, identify the caulk material currently in place. If it’s latex, you can paint over it, assuming it’s in good condition. If it’s silicone, remove excess caulk. Next, apply a paint primer. Then, add a thin layer of latex caulk. Let it dry, then paint over it.

This article explains how to make non-paintable caulk paintable. Read on to learn more.

puting the silicone sealant to caulk the joint between a washbasin and a wal

1. Identify the Material of the Existing Caulking

Before prepping a non-paintable caulk to make it paintable, identify what type of caulk is currently in place. This helps you figure out if you’ll need to strip it completely or if you can work on top of the existing caulking.

The following section explains how to tell what type of caulk you have and how to know if it’s paintable.

Types of Caulk and How To Tell if Caulk Is Paintable

There are four types of caulk used in home improvement projects:

  • Silicone: soft, flexible, and rubber-like
  • Latex: stretches lightly but easily tears apart
  • Polyurethane: stiff, bumpy, foam-like
  • Specialty: composed of other materials

By knowing which type of caulk is used, you can determine whether it’s paintable.

Find an inconspicuous area and use a utility knife to cut away at a small spot of the caulking. Examine the material. If it is soft, flexible, and rubber-like, it’s likely a silicone caulk. Silicone caulk is non-paintable. Paint doesn’t readily adhere to silicone, so there’s some prep work involved to make silicone caulk paintable.

More rigid, non-flexible, or flaky caulk is probably latex. It may have a light stretch but easily tears apart, especially if it’s old. Latex caulk is paintable. For painting, latex is the easiest to work with.

The one major downside to latex is that latex caulk is not waterproof. You should never use acrylic or water-based latex in bathrooms, around sink fixtures, or outdoors because it will rapidly deteriorate.

A stiff, bumpy, foam-like outdoor caulk is most likely a polyurethane sealant. You’ll usually see this type of sealant on the joints or in gaps of home exteriors. Polyurethane sealant is paintable.

There are also dozens of specialty caulks on the market. They’re not all-purpose caulks, and you’re less likely to come across these inside the home. For example, White Lightning Butyl Rubber Caulk is a cement sealant. It’s commonly used on gutters, roofing, pipes, and siding. Butyl rubber is a paintable caulk.

When Can You Paint Over Caulk

You should only paint over the caulk that’s currently in place if it is latex and in good condition. Latex caulk in poor condition should be stripped and re-caulked before painting. 

Silicone caulk, on the other hand, cannot be painted over. The paint will not stick, so you’ll need to know what to do if you have silicone caulk in place. The next several steps walk you through the process.

Related Posts:

2. Remove Excess Caulk From the Work Area

Paint will not stick to silicone caulk, so you must add a paintable caulk on top. However, you cannot apply paintable calk without first prepping the existing silicone caulking.

smoothing the silicone sealant between a washbasin and a wall using a spatula

Removing excess silicone caulk smooths the work surface, providing a fresh, flat space. This ensures the job turns out as smoothly as possible without looking sloppy or tacky.

To remove excess silicone caulk, use a utility knife to shave off any extra material. Even out the surface so that it lies as flat as possible, keeping things nice and smooth. Silicone caulk cannot be sanded down, so you must be meticulous as you work to keep things as neat as possible.

3. Prime the Work Area

Some silicone caulk takes well to primers, whereas others do not. The following steps will help you prime silicone caulk properly:

  1. After smoothing the surface of the existing silicone caulk, apply the primer according to the instructions on the packaging.
  2. Allow it to dry completely.
  3. Examine the caulk to see how it looks. If the primer appears to have adhered well and dried completely, you can apply a layer of paintable caulk.
  4. If the primer hasn’t fully dried over the silicone, you can wait a bit longer or choose to forgo the primer.
  5. Wipe the primer off and move on to the next step, sans primer.

4. Apply a Layer of Paintable Caulk

Apply a very thin layer of paintable latex caulk over the prepped silicone surface. Work slowly and deliberately, ensuring not to drop caulking on the surface below.

apply a layer of paintable caulk

After applying the caulk across the surface, use a spreading tool to smooth it along the surface before it completely dries. You want to avoid cracks, gaps, dips, or nicks, as the paint will leak into these areas, creating an unsightly appearance. 

Allow the layer of paintable caulk to dry completely.

5. Paint the Caulked Surface

After preparing and re-caulking the surface of the silicone, check again to ensure that everything is smooth and dry. Next, you can start painting.

Opt for a paint specially formulated for caulking. Most of these specialty paints feature detailed directions for use. Many even include a list of recommended paint types for use on their surfaces. If instructions aren’t included on the packaging, it’s best to go for an oil-based paint closely matched to the surrounding surfaces if you’re attempting to color-match.

Let the paint dry. Add a second coat if desired.

Final Thoughts

Almost any type of caulk can be made ready for painting. The process involves some basic preparation steps before applying the paint. 

The best caulk for home interiors, except for kitchens and bathrooms, is latex caulk. This caulk is paintable and easily smoothes before it dries, allowing you to create a seamless finish. Silicone caulk, on the other hand, is best for bathrooms and around sink fixtures. It’s water-resistant and durable, but it isn’t readily paintable.