Why Do My Drains Keep Clogging?
By the Duncan Family Plumbing team · October 10, 2026
A drain that clogs repeatedly, even after clearing it, usually means the real cause hasn’t been addressed — grease or hair buildup coating the pipe walls, tree roots growing into an older line, or a low spot in the pipe collecting debris. Snaking clears the symptom; finding the cause fixes it for good.
Grease, Hair, and Soap Buildup
Kitchen drains clog from grease that cools and hardens on pipe walls, narrowing the passage a little more each time. Bathroom drains build up hair and soap scum the same way. Each clearing removes the immediate blockage but leaves the coating that catches the next one.
Tree Roots
Older clay or cast-iron sewer lines are common root targets, especially near mature trees. Roots enter through tiny cracks or joints seeking moisture, then grow into a mat that catches paper and waste. A camera inspection is the only reliable way to confirm this without guessing.
A Low Spot or Bellied Pipe
Ground settling over the decades can create a dip, or "belly," in an underground line. Water pools there instead of flowing through, collecting solids until it clogs — and it will clog again at the same spot no matter how many times you clear it.
The Fix That Actually Lasts
If a drain has clogged more than once or twice, it’s worth a camera inspection to see what’s really happening inside the line. From there, hydro-jetting clears grease and root growth from the full pipe diameter, and a bellied or damaged section can be relined or replaced so the problem doesn’t return.