Drainlaying is licensed work in NZ — you cannot legally do it yourself or hire an unlicensed person to do it. Here's what drainlayers do, what it costs in 2026, and how to find a registered drainlayer near you.
What Is a Drainlayer?
A drainlayer is a licensed tradesperson who installs, alters, or repairs sanitary drains — the pipes that carry wastewater from buildings to the sewer or septic system, and stormwater drainage connecting to public stormwater infrastructure.
In NZ, drainlaying is regulated by the Plumbers, Gasfitters and Drainlayers Board (PGDB) under the Plumbers, Gasfitters, and Drainlayers Act 2006.
What Drainlayers Work On
- Sanitary drainage — sewer pipes from building to the property boundary connection
- Stormwater drainage — surface water collection, downpipe connections to public stormwater
- House drainage — under-floor plumbing, soil stacks, inspection chambers
- Septic systems and pump stations — on-site wastewater treatment installation
- Drain relining and repair — CCTV inspection, pipe patching, relining without full excavation
- Blocked drains — hydro-jetting, clearing, and repair
- Connection to council network — the physical connection at the property boundary to the public sewer
What Drainlayers Do NOT Do
Drainlayers work below ground and at the building's drainage system. Above-ground plumbing (taps, toilets, hot water systems) is plumbing work, regulated separately under the same PGDB but requiring a plumbing (not drainlaying) licence. Many tradespeople are licensed in both — check which licence your contractor holds.
Must I Use a Registered Drainlayer?
Yes. Under the Plumbers, Gasfitters, and Drainlayers Act 2006, drainlaying work must be supervised by a registered drainlayer. This means:
- A registered drainlayer (or licensed certifier) must personally supervise the work
- The registered drainlayer signs off a Certificate of Compliance on completion
- The work must comply with NZS 4404:2010 (land development and subdivision infrastructure) and local council requirements
Doing sanitary drainlaying work without a licensed drainlayer's supervision is an offence under the Act. Councils will not accept connections to the public network without a compliance certificate.
Check a drainlayer's registration: PGDB Register
Drainlaying Cost NZ 2026
| Work type | Typical cost |
|---|---|
| CCTV drain inspection (per property) | $350–$700 |
| Blocked drain clearing (hydro-jet) | $300–$600 |
| Drain repair — small crack or root intrusion | $800–$2,500 |
| Drain reline (no-dig, per metre) | $300–$600/m |
| New sewer connection — house to boundary | $3,000–$8,000 |
| Under-slab drainage — new build | $4,000–$12,000 |
| Stormwater drainage system — residential | $3,000–$10,000 |
| Septic tank installation | $8,000–$25,000+ |
| Inspection chamber installation | $1,000–$2,500 |
| Emergency call-out (blocked drain after-hours) | $350–$600 call-out + hourly |
All prices ex-GST. Prices vary significantly by soil conditions, depth, and whether excavation is required. Hard or rocky ground adds 30–80%.
Common Drainlaying Jobs for Homeowners
Blocked Drains
The most frequent call-out. Signs: slow drainage from multiple fixtures (indicates a main drain blockage, not just a fixture), sewage smell, gurgling, overflows at inspection chambers.
Most drainlayers carry hydro-jet equipment (high-pressure water) to clear blockages. A CCTV inspection shows whether roots, cracks, or settled pipes are the underlying cause.
Root Intrusion
Tree roots grow into drain joints and cause recurring blockages. Solutions: root-cut and re-block (temporary), drain reline (longer-lasting), or excavation and replacement of the affected section.
Drain reline (no-dig rehabilitation) inserts a new pipe within the existing one — no excavation required for accessible sections. Costs $300–$600/m but saves substantial excavation cost.
Old Clay or AC Pipes
Older NZ homes (pre-1980) often have clay earthenware or asbestos cement (AC) drains. These have aged well in many cases but can be brittle, settled, or heavily root-infested. CCTV inspection before buying an older home is strongly recommended.
AC pipes must be handled by licensed workers using correct PPE. Do not break or cut AC pipe yourself.
New House Connections
New builds and additions need a new or extended drain from the building to the boundary connection point. This requires: 1. Council application for connection 2. Licensed drainlayer installation 3. Council inspection before backfilling (in many councils) 4. Certificate of Compliance on completion
Septic System Replacement
Rural and lifestyle properties on septic. Modern septic systems (multi-chamber treatment with a disposal field) are designed for the site's soil permeability and wastewater load. The design, installation, and connection require a licensed drainlayer and council consent.
How to Find a Drainlayer Near You
Verify registration first: PGDB Register at pgdb.co.nz — enter the company or individual's name to confirm they are currently registered.
What to look for: - Current PGDB registration (licensed drainlayer or licensed certifier) - Insurance — public liability minimum $1M - Familiarity with your local council's requirements - CCTV equipment (for diagnosis before committing to major excavation)
Find a drainlayer near you: Drainlayers NZ | Post Your Job Free
Frequently Asked Questions
Can I do my own drainlaying in NZ? No. Sanitary drainlaying work must be supervised by a person registered under the Plumbers, Gasfitters, and Drainlayers Act 2006. Doing this work without a registered drainlayer's supervision is an offence. Only very minor maintenance (clearing a trap, for instance) may be done by homeowners.
How much does a drainlayer cost per hour in NZ? Registered drainlayers typically charge $90–$140/hr + GST for on-site time. Most jobs are quoted as a fixed price per job rather than hourly — request a written quote with scope and price before work begins.
How do I know if my drain is blocked or broken? Blocked: multiple fixtures draining slowly, sewage smell, gurgling sounds. Likely a blockage in the main drain. Broken: wet patches in the garden above the drain line, subsidence, tree root problems. A CCTV inspection ($350–$700) diagnoses the issue before spending on repairs.
What is a Certificate of Compliance for drainlaying? The COC is signed by the licensed drainlayer confirming the work complies with the Act and applicable standards. Councils require it before accepting connections to the public network. You should receive a COC on completion of any consented drainlaying work — keep it with your house records.
Do I need a building consent for drainlaying? Work within the building (under-floor drains, new fixtures) typically requires a building consent and a plumbing and drainage inspection. Work outside the building connecting to the council network requires council approval for the connection, and a drainage COC from a registered drainlayer. Check with your local council before starting.
Related: Plumber Cost NZ | Drainlayers NZ | Post a Job Free