Delivering high-quality, safe, and reliable, commercial and residential plumbing and drainage services for over 30 years.

Solutions at Scale

Grantham Group

Four Divisions.
One Trusted Name.

A person adjusting plumbing valves and gauges on a wall-mounted heating or water system in a utility room.

Trusted Plumbing, Drainage, and Hydro Solutions

Over 30 Years of Plumbing & Drainage Excellence

Grantham Group has delivered large-scale plumbing and drainage solutions across New Zealand for over 30 years.

With a team of 35+ experts and a reputation built on trust, safety, and performance, we are your partner of choice for complex commercial builds, high-end residential projects, and long-term maintenance contracts.

Find Out More

Multi-division plumbing and drainage services backed by over three decades of proven experience.

Assorted metal pipes and fittings on a work surface, some with threaded ends and a circular metallic component with bolts.

Plumbing

A yellow excavator digging into the soil at a construction site during daylight, with bare trees and a partly cloudy sky in the background.

Drainage

Worker in white coat and gray gloves is using a pipe inspection camera on a pipe underground, with the camera display showing inside the pipe, on a gravel surface.

Hydro

Residential Homes | Apartments | Subdivisions | Medical | Retail | Warehousing | Food Outlets | Offices | Hotels | Schools | Community Buildings | Infrastructure | Agricultural | Food Processing | Property

Architectural rendering of Takanini Library building with black and wood exterior, large overhanging roof, vertical wooden poles, and landscaped area around it.

Takanini Library by Architect: Pacific Environments

Expertise Across Every Sector

From residential builds to complex commercial developments, Grantham Group delivers plumbing and drainage solutions built for purpose, performance, and longevity.

Our team works across new builds, refurbishments, and fitouts supporting architects, builders, and property owners with the same precision and care, no matter the scale.

Projects

Auckland, Waikato, Christchurch and Queenstown,

With services across New Zealand, our experienced teams bring the skills, equipment, and project management expertise to support your next build on time, on budget, and to the highest standard.

Map of New Zealand with five location markers labeled 'GP,' 'GH,' and 'GD' in the Auckland, Waikato, Christchurch and Queenstown regions.

Plumbing: Auckland, Waikato, Christchurch, Queenstown
Hydro Services: Auckland, Waikato
Drainage: Auckland, Waikato

Our Valued Clients

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