Blistering on clay tiles happens when moisture gets trapped beneath the surface, causing bubbles or raised areas that eventually crack or peel. This can be due to manufacturing defects, poor installation, or harsh environmental conditions like intense sunlight combined with inadequate ventilation. Sometimes, the glazing on the tile surface can fail, allowing water to seep in and create these blisters. It's important to remember that not all tile discoloration or surface changes mean blistering, so a simple visual check for soft spots, loose tiles, or noticeable bumps can help you identify the problem. You might also gently tap the tiles to listen for hollow sounds, which could indicate moisture beneath. However, avoid walking on the tiles yourself to prevent damage—sticking to areas you can reach safely is key. Checking your attic or ceiling beneath the tile roof for signs of leaks or moisture buildup is an easy, safe way to spot issues early.
If you notice blistering or suspect moisture problems, it's wise to call in a professional roofing contractor experienced with clay tiles. Ask them how they plan to address the root cause—whether it’s improving ventilation, replacing damaged tiles, or applying a protective coating—and ensure their methods comply with your tile manufacturer’s warranty to avoid voiding it. A good question is: “Can you confirm that the repair approach won’t affect my clay tile warranty?” Additionally, inquire whether they perform thorough moisture assessments and what long-term maintenance they recommend to prevent blistering from recurring. Fixing blistering usually involves replacing affected tiles and correcting underlying plumbing or ventilation problems. Taking these steps ensures your roof remains both beautiful and durable for years to come.