G4/AS1, 5th edition

G4 Ventilation Acceptable Solution G4/AS1 Fifth Edition provides a compliance pathway for meeting the ventilation performance requirements of Clause G4 of the New Zealand Building Code, specifically for the ventilation of buildings and gas-fuel appliances. The scope of the document includes natural, mechanical, and combined ventilation systems for spaces within buildings, as well as specific provisions for gas-fuel appliances and flue locations. It is suitable for a wide range of building types, including residential and commercial. It references New Zealand and Australian standards and includes modifications to those standards. The fifth edition has been published in standalone format with improved clarity, consistent structure, and updated terminology. The acceptable solution references the Building Product Specifications for air handling systems. The fifth edition also includes minor amendments to correct formatting, grammar, and cross-references.