Quick and Easy Bathtub Caulking with Flex Shot

Quick and Easy Bathtub Caulking with Flex Shot was written by a member of the Flex Seal Editorial Team. 

Water damage is no joke; sometimes, it can be a silent destroyer of your walls and home. The main culprit? Your moisture-filled bathroom. But don’t worry, Flex Shot has your back when it comes to bathroom leak prevention. This rubberized, waterproof sealant can help protect your bathtub, shower and more. Keep reading for a quick and easy bathtub caulking tutorial with Flex Shot.

Materials Needed

● Flex Shot (colour of choice) 

● Box cutter or knife

● Paper towels

● Optional: Caulk remover and razor scraper 

Note: Before using Flex Shot, read all directions carefully and take proper safety precautions, such as being in a well-ventilated area and wearing protective gear while applying. 


1. Preparing to Use Flex Shot

Start by making sure your project area is clean, dry and free from grime, mildew or dirt. Next, remove any old caulk along the areas where you’ll apply Flex Shot. To do this, run a caulk remover along the previous caulk line and use a razor scraper to remove any remaining bits.

Now that the surface is prepped grab your can of Flex Shot and a box cutter or knife. Carefully cut the tip of the extension tube at a 45-degree angle so that it’s large enough to achieve the desired bead size. Please use caution when doing so.

Flexpert Tip: The farther down you cut the extension tube, the larger the bead size.

2. Bathtub Caulking with Flex Shot

Now that your surface is prepped, it’s time to seal out moisture with Flex Shot. To apply, simply push the extension tube to dispense the product. For a perfect bead, apply in a steady, even motion.

Some areas you may want to seal in your tub or shower include: 

● Around fixtures such as shower heads or nozzles, where they meet the tile  

Where the top of the tub meets the tile

● Where the tub meets the floor 

● Between the tile and the wall outside of the tub 

● Any corners, from the base of the tile to the ceiling

Flex Shot can be tooled within 20 minutes of application, so once your desired areas have been treated, take your finger and smooth out the product. Use a paper towel to remove any excess Flex Shot and allow approximately 24-48 hours for the product to fully cure.   

Once fully cured, Flex Shot remains flexible and waterproof and will not fade, dry, shrink, crack, yellow, or deteriorate. This makes it perfect for protecting your bathroom for years to come.  

Flexpert Tip: We do not recommend cleaning with harsh chemicals or scrubbing, as this may cause the product to become slippery or break down. Note that only white and almond Flex Shot are mildew resistant.  

3. Finishing Up and Storing Flex Shot  

Now that your bathtub caulking project is complete, it’s time to store Flex Shot properly. Remove the extension tube and clean it with a dry paper towel. Extend a small bead past the applicator tip to form a plug. This plug will cure and help the remaining product stay fresh. Pull or cut off this plug when ready to reuse.

Damage from leaks can quickly become costly, but staying proactive with Flex Shot can help you seal and protect your bathtub before leaks happen. Put your mind at ease by using the power of Flex Shot, and as always, we encourage you to stay inspired and see what else Flex Seal products can do for you.



By Amanda Tacconi

Amanda Tacconi is an Editor at The Flex Seal Family of Products, where she focuses on writing and editing articles for the company’s blog.

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