What Is Countertop Cancer and How to Prevent It

The term “countertop cancer” might sound dramatic, but it’s a real and costly issue many homeowners face. It refers to the slow, progressive damage that occurs when water seeps between the sink and countertop, especially in poorly sealed or aging installations. Over time, moisture infiltrates the counter material, causing swelling, warping, discoloration, and even mold growth. Left unchecked, this can mean a full countertop replacement—an expensive fix for something that started small.

One of the main culprits behind countertop cancer is improper sealing during sink installation. When the caulk or sealant around the sink fails, water from everyday use can slip into the smallest gaps. In materials like particleboard or MDF, which are common under many laminate counters, this moisture can cause the substrate to swell and crumble. Even stone counters aren’t immune—water can seep in and stain porous surfaces if they’re not sealed properly.

Signs of countertop cancer include soft or spongy areas near the sink, dark spots that indicate moisture damage, and gaps where the sink meets the counter. By the time you notice these symptoms, significant damage may have already occurred underneath the surface. That’s why prevention is key.

The best way to prevent countertop cancer is by ensuring a professional installation and regular maintenance. This includes choosing the right sink type for your counter material, applying high-quality waterproof sealants, and re-caulking as needed over time. Being proactive can save you thousands of dollars in potential repairs.

At I Hate My Sink, we take countertop cancer seriously. Our installation process is designed to protect your counters from moisture damage for years to come. Whether you’re replacing your sink or upgrading your counter, we’ll make sure both look great and stand the test of time.

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