Allco Projects - Auckland Central Library

Auckland Central Library

Project Requirements

This project required the refurbishment of existing concrete flat-roof as part of its maintenance plan to preserve the building.


Industry Sector



Allco’s Hydrotech MM6125 and Casali Torch On.

Project Details

Project Name: Auckland Central Library

Applicator: Sansom Construction Systems

Architect: Babbage Consultants Limited

Products Used: Hydrotech MM6125, Casali Torch On Membrane

Completed: December 2021

The Project 

Project Requirement:

To refurbish and waterproof the existing roof in order to preserve the building, its heritage and its contents for years to come. Removal of the existing old membranes from the main roof area including parapets and skylights structures, application of new waterproofing systems suitable for the development of a roof garden with the aim to improve storm water runoff, air quality and to set the example for other business and councils going forward.

Allco Solution:

The Library zero fall roof and green roof requirement meant our Allco’s Hytrotech membrane was the ideal solution for the ambitious project with the installation carried by one of our most experienced installers Sansom Construction Systems Ltd.

The existing old membrane was removed in entirety, the exposed concrete was cleaned and prepared for the application of Hydrotech MM6125. The roofing areas, parapets and main plantroom roofs were waterproofed with a combination of our Hydrotech and Casali membranes.

A large portion of the roof area is covered by a garden systems and the remaining areas are covered by gravel ballast provide both aesthetic appeal and protection for the waterproof membrane against foot traffic.
Allco has been able to work closely with the Babbage Consultants and our applicators Sansom Construction Systems Ltd on the green roof design requirements, providing the necessary support and technical expertise throughout the project.

Sansom is very proud to have been part of this iconic project with Allco Waterproofing. Allco’s Hydrotech was selected as the ideal membrane due to its proven track record on zero fall roofs and green roof overlay. The continued support and input from Allco’s Technical Advisors and Sansom’s experience, in combination with selecting the right waterproofing membrane, were key factors in the project’s success. – Steven Van Rhoon (Director, Sansom Construction Systems).

More than 2000 plants have been planted on the roof of the Auckland Central library in the CBD, creating the first Auckland Council “green roof” of its kind and size in the City of Sails and over the coming months, a further 300 to 400 plants will be planted to improve the overall coverage. Hopefully, it’s the start of many more green roofs in Tāmaki Makaurau.