Homestar is New Zealand’s environmental and energy rating for both new and existing homes, which is administered by the New Zealand Green Building Council (NZGBC). The aim of Homestar is to improve the performance and reduce the environmental impact of new and existing homes in New Zealand, making them warmer, healthier, and more comfortable places to live. Homestar encourages homeowners to make informed decisions that will improve the performance and comfort of their home. Homestar covers a wide range of topics including energy efficiency, water harvesting and efficiency, sustainable building materials, design, renewables, waste management and site usage such as native plantings and permeability. Qualified Homestar Assessors work with homeowners and designers to first complete a Design Rating for the home, which then gets confirmed as a Built Rating once the project has been completed to plan.

Earthwool® glasswool is the only product in New Zealand with GreenTag Level “A” rating, and qualifies for points under the Materials section of Homestar. It can also be used in Greenstar rated projects, which is the rating tool for commercial buildings such as office blocks.