Quick Answer
If a drain keeps blocking every few months, tree roots are almost certainly entering through a cracked or offset joint. Mechanical cutting is temporary, root foaming buys a few years, and pipe relining is the only true permanent fix.
You have had the drain cleared twice this year already. Six weeks later — slow drains again. Sound familiar?
In Sydney's older suburbs, tree roots are responsible for the majority of repeat drain blockages. Earthenware and old clay pipes are the worst offenders, but even PVC joins can let roots in once seals degrade.
How roots get in
Roots don't smash pipes — they find weakness. A hairline crack, a loose rubber seal, or a slightly offset join is enough. Once a single root hair enters, it thickens, traps debris, and within months you have a full blockage.
1. Mechanical cutting (temporary)
An electric eel or hydro-jet cuts the roots out. Quick, effective, and the lowest-cost option — but the roots will grow back. Good for renters or short-term homeowners who just need the line flowing again.
2. Root foaming treatment
A herbicide foam is flushed through the line to kill roots inside the pipe without harming the tree above ground. Treatment typically lasts several years before retreatment is needed. A solid middle-ground option when relining is not yet justified.
3. Pipe relining or replacement (permanent)
A resin sleeve is cured inside the existing pipe, creating a seamless new pipe within the old one — no digging required. It is the most significant up-front investment of the three, but it is the only true permanent fix and the new pipe is rated to last for decades.
Which should you choose?
If you have cleared the same blockage more than twice, stop paying for repeat jetting and get a CCTV inspection. We will show you exactly where the roots are entering and what the line actually looks like — then you can make an informed call.
Roots Keep Blocking Your Drain?
Mr. Clog offers CCTV inspection, root cutting, foaming treatments, and pipe relining across Sydney.