Can You Repair Chipped and Cracked Sinks or Tubs?

If you regularly read our blog, you’ll know that we recommend immediately replacing any toilet that has a cracked or chipped bowl. This is because your toilet constantly holds a lot of water, and once the porcelain is cracked and broken, it could split catastrophically at any time and release a small flood. But sinks and tubs only have water in them sometimes, and they shouldn’t ever be full of water if someone isn’t around to react to a plumbing emergency. So do they really need to be replaced?

Not usually! As long as the damage doesn’t go cleanly through the porcelain (visible both inside and outside of the sink or tub), you should be able to simply repair the damaged area. Because bathtubs and sink in particular receive a lot of daily use leading to substantial wear and tear over the years, you’ll need to remove and fully repair any weak points the chips or cracks bring to the porcelain. Chips and cracks on an even, flat surface will be easier to repair than damaged corners or other tight spaces. However, with patience, almost any repair should be within your skill set.

To get started, you’ll need to clean the surface thoroughly. Once every last bit of grime and soap scum has been wiped away, use a fine grit sandpaper (400-grit to 600-grit) to sand down the edges of the crack/chip. You want to smooth down any sharp points, but you also need to make the edge of the chip or crack roughened so the patching materials will adhere to the surface. Take your time and try not to scratch any of the unblemished porcelain surrounding the damaged area. When you’re done sanding, use a compressed air can with a straw to blow away any the dust. Wipe with a damp cloth to ensure the surface is clean once more.

You can buy porcelain sink crack repair kits online or from most local hardware stores. They vary a lot in price and quality, so try to look up reviews online. That will help you find a product that other homeowners thought worked well. While you’re at the store, skim the instructions quickly to see whether you’ll need a facemask. If you do need one and don’t have one at home, you won’t want to make a second trip back to the store, so buy it now.

Before you get started on your repair, take the time to actually read the directions. Many of these products are finicky, and if the directions aren’t followed exactly, they won’t work accordingly. We recommend taking your time. Many products need to sit before they can be used or after they’re applied, so grab a book or kick the kids off the TV, so you have something to entertain you as you wait. Remember to apply the repair product in very thin, light layers and allow them to dry before adding the next layer. If you add too much product too quickly, it may never harden correctly. You may need to add several layers, allowing it to dry each time in between applications. We understand that this can be tedious, but trust us — it’s less frustrating than adding a layer that’s too thick and which never cures.

Try to scrape away excess repair product as you see it. Don’t worry if there’s a little excess though; it will be sanded smooth once the compound has enough time to dry. When you’re happy with how the repair looks, allow it to dry completely. Often instructions will say to wait 1-3 hours, but we usually find waiting overnight provides more consistent results. In the morning, use your fine grit sandpaper to smooth the area flush with the surface of the porcelain. If the chip or crack is quite large, you may want to paint the area with a high-gloss paint or glaze to match the shine of your sink or tub. But it’s purely an aesthetic decision.

At Plumbing Paramedics, we’re here to help Calgarians with all their plumbing needs. In the case of porcelain sink crack repair, that means empowering homeowners to make repairs themselves! Of course, if you’d rather just have it replaced, we’ll be more than happy to help install your new sink or tub. Call us today, and we’ll schedule an appointment for you at your earliest convenience!