By Matthew Baring-Gould, Kingscliff-based drainage plumber. Servicing Tweed Heads for 4 years. 5.0 stars across 173 Google reviews. Licensed NSW 383340C and QLD 15036450. ABN 74 605 392 348.
Blocked sewer at a Brisbane property, repeat tree root problem. Set up the hydrojet on the left-hand side at the inspection opening, extended downstream. Hit the blockage at around 4 metres, which is exactly where the original earthenware line met the newer PVC. The join had either been done poorly or had worked loose over time, and the tree roots had found the gap.
What the customer called us for
Owner called us out. The property had tree roots in the sewer previously and the drain was backing up again.
What we found when we got there
Hit the blockage at around 4 metres downstream from the inspection opening. That is right where the earthenware line meets the newer PVC section. The join between the two materials is a known weak spot: one pipe is clay, the other is plastic, and no coupler ever seals them to the same tolerance as a straight join in a single material. Tree roots had found that gap.
Why we did it this way
Earthenware-to-PVC transitions are one of the most reliable places to find tree roots on an older Brisbane property. Earthenware was laid up until the 1970s. When sections failed they were typically dug out and replaced with PVC, leaving a clay-to-PVC coupling in the middle of the line. That join is not as tight as a single-material join and it moves differently with the ground. Over decades, every one of those joints becomes a candidate for root ingress. Knowing that pattern is why we go straight to the transition point when we hear ‘blocks every year, tree roots’.
What we did on site
- Set up the hydrojet on the left-hand side of the property.
- Undid the inspection opening.
- Extended the hydrojet downstream.
- Hit the blockage at around 4 metres, at the earthenware-to-PVC transition.
- Switched to the root ranger attachment and cut out the root mass.
- Ran the CCTV camera through and confirmed the line was clear.
- Flagged the transition join as the long-term fix target for a future repair or reline.
The result
Line cleared on the day. Customer has a camera report, the location of the transition join marked, and the explanation for why the roots keep coming back to the same spot.
If you have the same issue
If you have an older Brisbane property with a tree-root blockage that keeps coming back, the problem is almost always a cracked junction or a clay-to-PVC transition join. Clearing the roots is the first step. Repairing or relining the join is the only way to stop the next callout. Call Matty on 0447 188 394 or request a quote.
Customer names and addresses have been withheld. Individual results vary. Drain Masters Plumbing is licensed in NSW (383340C) and QLD (15036450).
Frequently asked
Why do clay-to-PVC joins leak more than clay-to-clay or PVC-to-PVC?
The two materials have different thermal expansion, different surface textures, and different standard outside diameters. The coupling between them relies on a flexible rubber seal that works well new but ages differently on each side. Over decades, the seal loses grip on one side first and the join opens.
How do you locate a transition join without digging?
The CCTV footage shows the material change clearly: smooth white PVC on one side, rough brown clay on the other. The camera’s inbuilt transmitter lets us surface-locate the exact point with a locator wand.
Can the transition join be fixed without digging it up?
Yes, in most cases. A pipe reline runs a resin-infused liner through the full section, sealing the transition join from the inside without excavation. On a driveway or path, that is usually the cheapest permanent fix.
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