Learning how to caulk a shower is a rewarding DIY skill because it’s likely you’ll have to repeat it year after year to keep your bathroom or shower area looking fresh. Over time, dirt and grime can collect in the corners of the bathtub or shower enclosure, or the grout itself can simply collapse, allowing leaks into the fabric of your home.
The good news is that caulking a shower is a simple task and repairing faulty or dirty caulking really won’t take long. It’s also a job that can be done at the same time as grouting tiles if you’re renovating them as well. Take part of your weekend for a simple caulking job.
How to caulk a shower
If you already know how to caulk a bathtub, you’re all set. If this is your first time tiling in a shower, you will likely also need to learn how to caulk a shower. All you need is a little patience, a few DIY tools and some handy tips. However, keep in mind that you can’t hop in the shower until the grout has set, which may take a day or two.
You will need:
1. Prepare the surface
It’s best to work on a completely dry shower, so open the window after use to allow moisture to escape from the room. Wipe down surfaces thoroughly with a cloth or paper towels and allow to dry completely, overnight if possible.
If you are in a hard water area, scale may have built up around your joints. Put on your protective gear and first solve this by soaking paper towels in vinegar and letting them sit for about half an hour – cleaning with vinegar saves you from having to buy more chemical cleaning products. While waiting, check a few times to see if the vinegar will damage the surface. Rinse and wipe dry.
2. Remove the old gasket
Next, put a duster in the shower to catch the old grout and make sure it doesn’t go down the drain. This will also ensure that your shoes don’t scratch the shower tray. Use a sealant remover to remove the old caulk. Apply to all previously sealed areas – in and out of the shower – following package directions, waiting the recommended time (which can be up to three hours), then scrape off with a plastic scraper.
You can also tackle old grout with a utility knife, box cutter, or razor scraper, but angle the knife carefully to avoid cutting into surfaces, or use the plastic razor recommended above. Pull off any remaining bits with pliers or tweezers or if stuck soften with sealant remover and scrape with the smoother tool. Finish with a non-abrasive pad or, for delicate surfaces, a cloth dipped in denatured alcohol.
3. Preparation for caulking
If there is mold or mildew along the grout, it will haunt you, so blot a cloth with some bleach mixed with water, apply, and then rinse. After drying, wipe all joints with denatured alcohol on a cloth. To ensure you can apply the sealant cleanly, stick strips of painter’s tape along the joint, leaving a small gap between them to line the joint.
4. Caulk the shower
The sealing area must be completely dry. Cut off the end of the silicone sealant cartridge. Carefully cut the nozzle at a 45 degree angle. “Start by cutting off a small amount,” says Beth Pearce, category manager for construction and interiors at B&Q (opens in new tab). “You can always cut more off afterwards if you think you need a larger bead.”
Screw the nozzle onto the cartridge and insert it into the cartridge gun. “Using a sealer gun is easy, but you might want to do a little practice first to get an even bead of sealer,” says Beth. ‘A few simple steps and you’re good to go.’
Run the sealant along the joints and squeeze the handles evenly to loosen it. Run the smoothing tool along the seam or use a finger dipped in dish soap, then remove the painter’s tape. Although it forms a skin quickly, silicone sealant can take longer than a day to fully cure. Follow the directions on the packet for when you can shower again.
What Happens When You Caulk Old Gaskets?
If the shower is old and hasn’t had a history of maintenance, it may have built up layers of clumpy, bumpy caulk. This may have broken up in places where water can pool and harbor areas of mold and dirt. Covering it up is a bad idea. It’s much better to scrape off the old grout to provide a level, clean surface for the new grout.
What to use to seal a shower?
The most suitable caulk for a bath or shower area is silicone. This sealer is waterproof – essential for a shower area – but that also means the surface must be completely dry when applied or the silicone will not adhere. For a flawless result, choose a silicone gasket that’s labeled for bathroom use and also resists mold.