Concrete tiles expand and contract due to changes in temperature, a process known as thermal movement. When the sun heats the tiles, they expand, and as the temperature drops, they contract. Because concrete is a rigid material, repeated thermal movement can cause tiles to crack, loosen, or shift over time, especially if they weren’t installed with enough spacing to accommodate expansion. This movement is more noticeable in regions with large daily temperature swings. You might notice a few cracked tiles, small gaps forming between tiles, or tiles that seem slightly misaligned. A simple way to check is by looking for visible cracks or uneven tiles on a sunny day compared to cooler conditions. If your roof shows such signs but no leaks, you may have early-stage thermal movement issues.
For DIY checks, inspect the roof closely after very hot and cooler days, noticing if tiles shift or crack more in heat. Avoid walking on the roof if you’re not experienced, as tiles can be fragile. If you see significant cracking, loose tiles, or water stains inside your home, it’s time to call a roofer. When speaking to a contractor, ask how they accommodate thermal movement during installation, such as spacing or use of flexible underlayment. Also, inquire about their approach to repairs—do they replace only damaged tiles or adjust the entire section? Proper installation and timely maintenance can keep concrete tile roofs performing well despite thermal movement.