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5 Good Reasons to Caulk Your Toilet

5 Good Reasons to Caulk Your Toilet

Many people may not pay much attention to it, but most toilets have a thin, white seal—known as caulk—around their base where they meet the floor. And, believe it or not, this caulking rests at the core of a long-standing debate among DIY home-improvers and professional plumbers: should toilets be caulked or not?

There are many good reasons why you should caulk your toilet:

  • Caulking prevents odors.
  • Caulking hinders germ growth.
  • Caulking secures the toilet in place.
  • Caulking has aesthetic benefits.
  • Caulking is required by the International Plumbing Code.

Depending on the professional you talk to, they may recommend using caulk or not using it at all; some may even suggest a middle ground, where you only apply the sealant to some areas of the toilet base. While there are valid points to all sides of this caulk argument, most will say it is more beneficial to use it rather than not.

Why Do Some Recommend Not Caulking a Toilet?

Whether or not you should caulk your toilet has been the subject of debate for years. While many professionals recommend caulking a toilet, a good number of people believe it can cause more harm than help.

The Argument Against Caulking

What is the argument for not caulking? The reasoning behind not caulking a toilet stems from leaking water issues:

For one, if your toilet has a plumbing issue like a leak, it can be hard to tell as long as it has caulk around it. Both small and large leaks could go undiscovered for a long time. In addition, if there is caulk present, a large amount of leakage will have nowhere to escape but onto the floor, where it can cause severe water damage to it and other areas surrounding the toilet.

If there is a leak, those against caulking believe that the caulk seal makes it quite difficult for people to break through to reach and repair the source. Upon breaking the seal, there is a chance you could damage the floor.

Finally, those against caulking believe that the rubber or wax seal that is already present in toilets is designed to help prevent leakage and sufficiently fulfills any plumbing codes that require sealing, so there is no reason to add an additional seal.

Misconceptions Behind Caulking Toilets

While all of the previous points are understandable concerns for applying caulk around a toilet, there are a few common misconceptions that require clarification. First, toilets can only leak through the floor, not necessarily on it. In fact, it is quite rare for a toilet to leak onto the floor. Most toilets that leak will deposit water into the basement or subflooring of a home. If it begins to pool around the toilet base, then there is likely something wrong with the wax seal underneath it.

Also, it is not impossible to remove caulk if you need to get to the source of a toilet’s leak. The best way to remove caulk sealant around the fixture is to use a razor blade scraping tool. With this tool, you should be able to cut through the caulk so that it can be pulled up and removed from the toilet base. If you find the caulk is hard and difficult to cut through, consider using a specialized caulk remover solution to dissolve it.

Finally, we must address the rubber or wax seal that often comes with toilets. While it is true they are made to help prevent leaks, wax seals become less effective when placed on an uneven floor. Over time—especially without a caulk seal in place—the toilet can work itself loose, damaging and even breaking the wax seal underneath. It is often the wax seal’s failure that leads the toilet to leak from its base to begin with.

So, although water leakage is a fair assumption as to why caulking your toilet can lead to greater damage down the road, there are far more benefits to it than people realize. However, if you still feel uncomfortable with caulking your toilet, some professionals suggest caulking around most of the toilet and leaving the backside unsealed.

5 Good Reasons to Caulk Your Toilet

The following are a few reasons why plumbing professionals recommend caulking your toilet:

1. Caulking prevents odors.

Caulk essentially acts as a type of seal between your toilet and the floor. Without it, it can be easy for spilled bathwater or mop water—or, worst-case scenario, overflowing toilet water—to get in-between those crevices, which can be difficult to clean up.

The stagnant water will eventually produce an unpleasant mildew smell or other odor around your toilet. Left long enough, the standing water can promote mold and bacteria growth, which can produce even more unwanted odors.

Also, not caulking the toilet base can invite sewer-based odors into the bathroom, especially if there is a leak with the wax or rubber seal underneath it. Rather than risk having the entire bathroom smell like city sewers, many prefer to have a caulk sealant around the toilet base precisely for that reason.

2. Caulking prevents germ growth.

This point goes along with the first. Earlier, we talked about how standing water can lead to the growth of mold and bacteria. Why? Dark, moist crevices—such as the unsealed gap between a toilet base and floor—are perfect breeding areas for harmful bacteria; they love this environment.

However, as long as you have a caulk seal in place, your toilet will be less likely to harbor these germs. Another benefit to caulk is that you can easily clean it as you clean your bathroom floor. To further keep this area of your bathroom sanitary, you can also clean the caulk’s top layer using a mixture of hydrogen peroxide and water or vinegar and water. To scrub off more difficult stains, you can use a small toothbrush.

3. Caulking keeps the toilet in place.

The last thing you would want as you sit down on a toilet is to have it wiggling around. Caulk has a strong enough adhesive property to help anchor a toilet to the floor, even if the floor is uneven. In addition, the movement prevented by the caulk will ensure that the wax or rubber seal under the toilet does not break.

4. Caulking has aesthetic benefits.

Those against using caulk believe that it can leave behind unsightly stains or smear marks if it is applied improperly. On top of that, people argue it is nearly impossible to remove caulk from the floor once applied without damaging the floor surface.

However, with the right tools, it is easy to apply caulk neatly without compromising your floor. Many caulking solutions are also water-based, making them quite easy to clean up with regular soap and water. Also, a toilet base lined with caulk looks much nicer to the eye than a toilet with a gap between the floor and its base.

5. Caulking is required by Plumbing Codes.

Finally, caulking is required by the International Plumbing Code as well as the Uniform Plumbing Code. Both codes mention that areas in which fixtures (such as toilets) come in contact with the walls or floors should be sealed and water-tight. Because caulking around toilets is considered an industry standard for toilet installations, why not use it?

What is the Best Caulk to Use Around a Toilet?

By now, you probably understand the full importance of caulking a toilet, but how do you know which caulk is best to use in the first place?

Choosing the Right Caulk

There are quite a few different types of caulk available online and in home improvement stores, but it is essential to learn which solutions work best with sealing toilet bases. There are four main types of caulk to consider:

Rubber Caulks

According to This Old House, these caulks are usually “made with rubber compounds such as butyl, isoprene, butadiene, nitrile, and styrene.” The main benefit of rubber-based caulk is that they easily stick to multiple surfaces and are super water-resistant. However, they are often only recommended for outdoor use due to their flammability and the harmful fumes they produce. They are also very sticky and, therefore, challenging to tool.

Latex Caulks

Also known as acrylic or vinyl caulks, this type of sealant is water-based and, therefore, the easiest to use and tool. They are also inexpensive compared to other caulking solutions. However, latex caulks are not as long-lasting as other types of sealants, so if you end up going with a latex caulk for your toilet, try looking for those that also contain silicone since this material helps strengthen it.

Silicone Caulks

Silicone caulks have a strong adhesive, are completely waterproof, and very flexible; therefore, they are among the better options for toilet base sealing. In fact, they are the most common type of sealant offered for indoor and bathroom use, especially since they are very easy to remove and replace as needed. However, their unique qualities make them slightly more expensive as far as sealant options go.

Polyurethane Caulks

These sealant types are extremely durable and are known to be resistant to tears and abrasions. Also, polyurethane caulks are very adhesive and can stick to most surfaces easily. They are also flexible, waterproof, and weather-resistant, so when combined with its other features, polyurethane caulk offers the best sealant solution for toilet bases. However, because this caulk can prove to be difficult with tooling, you will need to use a solvent to clean up any messes.

Highly-Recommended Caulk Options

The following are some of the highest recommended caulks for toilet applications:

1. GE GE281 Silicone Kitchen & Bath Sealant Caulk

General Electric (GE) is a well-known brand that offers different caulking solutions for plumbers and DIY home-improvers. Their GE281 Silicone Sealant Caulk is relatively inexpensive and comes in a squeezable tube to make the application process easy. The product offers 10-year mold-free protection, as it is resistant to odor and stain-causing mold and mildew growth.

2. DAP 18001 Kwik Seal Caulk

DAP is another brand known to provide caulking products. Their DAP 18001 Kwik Seal Caulk is also quite inexpensive when purchased by the tube, and has similar mildew-resistant, water-tight properties to the GE281 sealant caulk.

One thing that makes the Kwik Seal Caulk unique is that it bonds similarly to glue but dries as a durable caulk seal. In other words, the substance is quite flexible, so it tools easily around the base of toilets while also being easy to clean up.

3. DAP 08640 Bathroom Silicone Rubber Caulk

The DAP Bathroom Silicone and Rubber Caulk can help seal nonporous surfaces around ceramic tile and plumbing fixtures such as toilets. It has long-lasting flexibility and is resistant to cracking and crumbling. The caulk provides a strong, water-tight seal following application.

4. GE GE012A Silicone All-Purpose Sealant Caulk

Another solution from the GE brand, the GE012A Silicone All-Purpose Caulk, claims to be “permanently waterproof” after application, in addition to being weatherproof. It is a strong adhesive and can stick to most wood, metal, vinyl, drywall, plaster, glass, and plastic materials.

The caulk is also flexible and shrink and crack-resistant. Unlike other products, this caulk appears clear in color rather than white.

5. Gorilla Silicone Sealant Caulk

Although it is not a common brand for caulk, the Gorilla Silicone Sealant Caulk is very versatile and is completely waterproof and mold and mildew resistant. It does not yellow, shrink, or crack, making it a great choice for long-term sealing. It also dries quickly and can be exposed to water in as little as 30 minutes.

Other reputable brands that offer quality caulk solutions for toilet base applications include 3M and OSI. Many of their products are not easily available online, but you are likely to find them at your local home improvement store.

How Do You Apply Caulk Around a Toilet?

Once you have figured out which caulk is best for your toilet, you will then be ready to apply it.

There are only a handful of methods to apply caulk, but the most effective application includes using a hand caulking gun or squeezable tube, especially for water-based caulk. A caulk gun allows you to create a straight, consistent bead of caulk along the toilet base, while a squeezable tube will allow you the ability to tool caulk into the shape you want to achieve.

Regardless of if you plan on using a caulk gun or tube, here are a few tips to ensure you successfully caulk your toilet base with that perfect seam:

  • Before starting, make sure you have the appropriate tools on hand, such as a small caulking tool kit or a caulking gun if you are using a caulk cartridge rather than a squeezable tube.
  • Most people do not think about this, but be careful about how you cut the tip of a tube open. If you cut too far down, you will create an opening that is too big, which will result in thick beading that will require additional tooling. The ideal opening size should only be slightly smaller than the bead you plan on applying. Also, make sure that you cut the tube tip at an angle, no more than 45-degrees.
  • If you are not confident about creating a smooth caulk line without making a mess of the surrounding floor or toilet base, use masking tape to both sides of the seam before caulking. The masking tape will also ensure that you produce straight, even lines with the seam.
  • Make sure you keep the tip of the caulk bottle or tube moving as you apply it around the toilet base. Try to maintain a steady dispensing pressure so that the caulk comes out evenly.
  • If you need to tool a water-based caulk into place or shape, you can use your index finger after dipping it in water or an ice cube. For silicone and polyurethane caulk, use a plastic spoon or caulking tool. With polyurethane caulks, specifically, you will need to wet the tool surface with a solvent first to prevent sticking and achieve smoother results.
  • After tooling, allow the caulk to sit for at least 24 hours to dry and harden.

Final Thoughts

If you want to prevent unwanted odors and germ growth and avoid annoying guests with a rickety toilet, caulking is the best way to go. It is quite an affordable investment and can be found at your local home improvement store or online. In addition, caulk is easy to apply, regardless of if you are installing a toilet in the bathroom for the first time or want to add a sealant to a pre-existing unit.

In conclusion, there are more benefits to caulking a toilet than meets the eye, so it is worth trying.