Are you QBCC licensed?

Yes. Plumbing and drainage work is carried out under QBCC occupational licence PD21658, held by Jamie Gary Moore in both the plumber and drainer classes and current to 1 September 2027. The number can be checked on the QBCC licence register before you engage us.

What causes repeated drain blockages?

Repeat blockages in the same line almost always indicate a structural defect rather than what was flushed: tree roots entering at a joint, a cracked or partially collapsed section holding solids, or a sag that has removed the fall.

Is drain relining better than replacing the pipe?

Relining suits long runs of structurally sound pipe with cracks or root intrusion, and it avoids opening driveways and gardens. A fully collapsed or badly deformed section has no host pipe to line against, so excavation and replacement is required.

How is a blocked drain located without digging?

The line is cleared with high-pressure jetting, then a CCTV camera records the defect while an above-ground locator marks its position and depth on the surface. Only the section needing repair is then excavated.

Guide 04 · Failure & repair

Blocked, cracked and collapsed drains

A drain that blocks repeatedly has a structural defect, not a usage problem. Jetting clears the line so a CCTV camera can record the cause — root intrusion, a cracked or displaced joint, a sag that has removed the fall, or a collapse — and the footage determines whether a section repair, a reline or full replacement is the honest answer.

Last reviewed September 2026 · Based on JMP Group field work in South East Queensland

Symptom, cause and the repair that follows

What you notice	Usual cause	Repair
Blockages every few months	Roots entering at a joint, or a cracked section trapping solids	Replace or reline the affected length and remove the root path
Sewage surcharging at the outside gully	Full blockage downstream, sometimes in the authority's main	Clear, camera, then establish which side of the connection owns it
Every fixture draining slowly	A sag in the line, insufficient grade, or heavy scale	Re-lay the section to correct fall and record the new inverts
Soft ground or a sinkhole in the yard	A leaking or collapsed pipe washing out its bedding	Excavate, replace pipe and bedding, compact in layers, reinstate
Gurgling fixtures with no blockage	Venting restricted, or a partial obstruction downstream	Camera the line, clear the restriction, correct the vent
Smell around the house	Broken inspection opening, dry trap or damaged vent pipe	Locate the breach, rectify it and re-test the system

Why drains fail in South East Queensland

Three local conditions account for most of the failures we excavate.

Old earthenware and terracotta pipe. Houses built before PVC became standard sit on short lengths of earthenware with mortared or rubber-ring joints. The material is brittle, the joints are numerous, and both are an open invitation to roots.

Reactive clay soil. Brisbane, Logan and Ipswich clay swells in wet weather and shrinks in drought. The ground moves, the pipe moves with it, and joints open or crack — which is why failures cluster after a wet season following a dry one.

Trees planted over the alignment. Roots follow moisture and enter at the smallest defect, then thicken until they hold back solids. Cutting roots restores flow temporarily; the pipe keeps supplying water until the defect is repaired.

A fourth cause turns up on renovated properties: a drain crushed or misaligned by later construction. Footings, pier holes, driveways and pool excavations all land on top of pipework nobody located first. Service location prevents it.

Repair, reline or replace

Section repair

Excavate the defect, cut out the failed length, replace with new pipe and bedding, compact and reinstate the surface.

Right when: a single defect sits in otherwise sound pipe and the ground above can be opened.

Relining

A resin liner cures inside the existing pipe, sealing cracks and joints without excavating the full length.

Right when: a long run is structurally intact but cracked or root-affected, and driveways or mature gardens sit above it.

Full replacement

The line is re-laid end to end in new material, to correct grade, with new inspection openings and as-constructed records.

Right when: footage shows defects along the whole run, the grade is wrong, or the pipe has collapsed.

Repairing one metre of a pipe that is failing along twenty buys a few months. The footage is what separates those two situations, and it costs a fraction of the repair it informs.

What an insurer or body corporate needs

Camera footage of the defect with distance from the access point
Surface-marked position and approximate depth
Pipe material, diameter and condition of adjoining lengths
A written scope separating investigation from repair
Confirmation of whether the defect sits on private or common property

Before we arrive, what helps

Which fixtures are affected, and whether it is all of them
When the problem started and how frequently it recurs
Any previous clearing or repair work on the same line
Where the inspection openings and the overflow gully sit
Recent construction, landscaping or tree planting on the property

Questions

Will a chemical root killer fix it?

Root treatments kill what is inside the pipe and leave the entry point open. The roots return because the moisture source has not changed. Sealing or replacing the defective joint is what ends the cycle.

How long does a repair take?

A single excavated section repair is typically a one-day job once the line is located and approvals are in place. Depth, rock, concrete surfaces and service crossings extend it, and the quote states the expected duration.

Can I use the bathroom during the work?

Water use has to stop while the drain is open and disconnected. We nominate that window in advance so occupants can plan, and on longer jobs we stage the work to restore service overnight.

Does a repair need council approval?

Like-for-like repair of a damaged drain is generally maintenance. Altering the alignment, the grade or the connection moves the work into a category requiring approval. Approvals guide.

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