Can You Caulk over Grout in the Bathroom?

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Pretty tiles without adequate care will crumble in a short time. Fortunately, there are protective measures to take before, during, and after installing tiles and other bathroom fixtures. Cracks in the bathroom grout occur without proper protection, so can you caulk over it as a solution?

You can caulk over grout in the bathroom as a temporary fix. The differences in the natures of caulk and grout make them unlikely to bond for a long time. Your best option is to plan for a permanent fix to the grout problem while caulk holds the fort.

This article looks into whether you should seal grout in a shower and the possibility of caulking over grout in the bathroom. I also explore how long you should wait after grouting before you caulk.

Should Grout Be Sealed in a Shower?


Grout in the shower needs sealing because its porosity is a big issue. This is because grout absorbs liquids it comes into contact with. For your kitchen backsplash, you may not need to seal the grout.

However, the bathroom has a lot of moisture, and sealing the grout will block out moisture that it would otherwise absorb. If water gets stuck behind the tile, mold and mildew can form.

The type of grout you use dictates the need for sealing. An epoxy-based grout can do without sealing because it will naturally repel water in your shower. More traditional grouts comprise sand, and you need a sealant.

The two primary types of sealant are:

  1. Membrane-forming sealants: These sealants form a water-repelling coating on the grout’s surface. The layer traps water under the tiles and makes the adhesive unsuitable for bathrooms.

Membrane-forming sealants don’t adhere to glazed tiles and are perfect for natural stone tiles. They fare better with kitchen floor tiles, the backsplash area.

  1. Penetrating sealants: With a water/mineral spirit as their base, these sealers allow the small silicone particles or latex particles to penetrate the grout. The latex or silicone mixes with the grout and out the moisture.

The methods of applying grout sealants are varied, including:

  • Roller application: A roller moves the grout down the line and rarely needs touch-ups.
  • Brush-on: A small brush tip applies the sealant to the area, taking a long time.
  • Spray-on: The sealant only soaks into the grout, not the glazed tile, and it wears off over time.

For the best results, seal and reseal your grout every six months in high-traffic areas and once a year in low-traffic areas. A high-traffic bathroom is one you use daily, while a guest bathroom is low-traffic.

Can You Caulk over Grout in the Bathroom?

As a homeowner, nothing is more annoying than repairing small areas of cracked or broken grout. It is unsettling to see such cracks in a new or recently remodeled bathroom (in the bathtub or shower area).

Four ways you can fix the cracks are:

  • Cover them up with more grout
  • Apply caulk over the grout and its cracks
  • Completely replace the grout with caulk
  • Re-grout the area

Of the four options, re-grouting the area is the best option. You can remove all the grout, clean the site, and reapply a fresh mix.

Caulking over grout is a temporary solution if you can’t re-grout. The area of the bathroom also affects whether caulking over grout will work. Shower corners are unsuitable to hold caulk over grout. In theory and practice, it’s unadvisable to caulk over grout.

Here’s why you shouldn’t do it until it’s necessary:

  1. The caulk will peel: Within a few days or weeks, you’ll notice the caulk flaking off the surface of the grout or peeling. This will take you back to square one when this happens.
  1. There’s a risk of mold and mildew: It’s not unusual to find molds and mildews growing between the grout and caulk if the patched area is exposed to moisture. The mold can spread to your walls and flooring, leaving ugly patches all over your house.
  1. It isn’t pleasing aesthetically: Caulk and grout have different colors, so mixing them in this manner might be unsightly.

Caulking over the grout cracks properly can help you avoid the development of mold. You want to pay attention to doing the correct thing because mold is harmful to your health.

Suppose you insist on caulking over grout in the bathroom. These are the steps you should take for the best results:

Select the right caulk for your purpose

Pure silicone, vinyl latex, adhesive, and acrylic latex caulk are a few of the many types of caulk to choose from. They all have specific features, so you should consider your needs and select one that fits.

For instance, acrylic caulk is unsuitable for shower purposes because it shrinks with variations in temperature and moisture. On the other hand, siliconized acrylic caulk is perfect for shower use because it’s sticky and doesn’t shrink.

Transparent caulk is best for layering over the grout, and you should choose caulks like these for the bathroom.

Clean the surface

Remove all broken or crumbling grout pieces with a handheld vacuum or hand broom. Caulk will adhere better to clean surfaces.

Use bleach and a toothbrush to clean the grout you will caulk over. This will prevent mold and kill any bacteria you might trap when applying the caulk. Wait for 24 hours for the area to dry properly.

Prepare your caulk gun and apply the caulk

Once you set up your caulk gun with the caulk tube, apply caulk to the gaps. You must place the nozzle’s tip 45-degrees to the surface and apply the caulk carefully. Press the trigger gently, and you will push the caulk out.

Keep a consistent pressure on the trigger as you drag the gun backward across the area you are caulking. Use a damp finger, the back of a spoon, or the nozzle’s tip to smooth out the caulk for a clean result.

Press firmly when smoothing out the new caulk to ensure that it enters deep into the grout joint. Finally, wipe the area along the joint line with a cleaning cloth to remove excess caulk and prevent it from drying on the tiles.

This is a cheaper, easier, and faster hack for crumbling grout, but it is temporary. Remember to re-grout any cracks or holes in your grout to avoid pests, water leakage, and mold.

How Long after Grouting Can I Caulk?

Tile caulking manufacturers have no specific instructions on the order of caulking and grouting. However, caulking before grouting a bathroom has major downsides. If you are a DIY enthusiast, you must grout first, wait for a while, then caulk.

After grouting, you should leave the grout lines open and clean the areas where you want to apply the caulk. Wait for at least 24 hours before caulking the area. This waiting period is crucial for places requiring extra protection, like bathrooms.

Grout is waterproof, with properties that prevent it from adhering to caulk. Caulking your shower is a protective measure against expansion and moisture, and it may be difficult for you to caulk before grouting.

Twenty-four hours isn’t too long, so keep your bathroom dry and follow this process. In this way, you will have adequate protection in your bathroom and avoid cracks in the grout.

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