AS 4254.1-2012 Ductwork for air-handling systems in buildings, Part 1: Flexible duct
Standards Australia
Supersedes: AS 4254-2002 Ductwork for air-handling systems in buildings
Supersedes: AS 4254-2002 AMDT 1 Ductwork for air-handling systems in buildings
Supersedes: AS 4254-2002 AMDT 2 Ductwork for air-handling systems in buildings
Draft Designation: DR AS 4254.1After consultation with stakeholders in both countries, Standards Australia and Standards New Zealand decided to develop this Standard as an Australian Standard rather than an Australian/New Zealand Standard.
Independent studies in both Australia and the USA have estimated thermal energy losses in the vicinity of 20% to 40% in flexible duct systems due to ineffective air and vapour sealing, poor installation practices and insulation being thermally deficient for the application into which it is installed.
The current NCC requires different thermal ratings for insulation used on flexible duct, depending on the climate zone and the application it is installed into. This, in conjunction with the increased energy efficiency requirements for new constructions, along with rising costs of energy is driving the requirement for more efficient flexible duct systems.
This Standard is Part 1 of a series on ductwork for air-handling systems, as follows:
AS
4254 Ductwork for air-handling systems in buildings
4254.1 Part 1: Flexible duct
4254.2 Part 2: Rigid ductwork
The main changes from the 2002 edition of AS 4254 are summarized as follows:
(a) Definition for ‘flexible duct system’ has been added.
(b) Flexible Duct Compliance Report Summary (FDCRS) has been modified and has become mandatory. Copies of original NATA test reports referenced in the FDCRS shall be provided upon request.
(c) Requirements for flexible duct in wet areas, such as bathrooms, toilets and laundries, have been modified.
(d) Requirements for applying duct tape to provide total air and vapour seal have been modified.
(e) Requirements for validity period for test results have been added.
(f) Mandatory requirements for labelling of flexible duct have been added.
(g) Requirements for installation have been modified.
(h) Requirements for hanger support and load distribution systems have been modified.
(i) Layout has been restructured.
The term ‘normative’ has been used in this Standard to define the application of the appendix to which it applies. A ‘normative’ appendix is an integral part of a Standard.
Originated as part of AS4254-1995. Previous edition part of AS 4254-2002. Revised in part and redesignated as AS 4254.1-2012.
This Standard specifies requirements for materials, construction and installation, including some aspects of performance, for flexible duct for air-handling systems in buildings and facilities. It covers—
(a) dimensional stability (deformation and deflection) under positive or negative pressure applications and static loads;
(b) leakage under positive or negative pressure;
(c) support; and
(d) fire hazard requirements.
This Standard does not cover the following:
(i) Noise generation and transmission.
(ii) Exposure to damage from—
(A) transportation and handling;
(B) weather and temperature extremes;
(C) flexure cycle;
(D) chemical corrosion; and
(E) other in-service conditions specific to the installation.
(iii) Impact loading, such as—
(A) fire;
(B) earthquake;
(C) sudden stoppage of airflow; and
(E) resistance to
Contents:
Section 1: Scope And General
Section 2: Construction And Installation
Appendix A: Flexible Duct Compliance Report Summary
Ventilation and Air Conditioning.
Air Conditioning and Mechanical Contractors Association; Australasian Fire and Emergency Service Authorities Council; Australian Building Codes Board; Australian Institute of Refrigeration Air Conditioning and Heating; Chartered Institution of Building Services Engineers; Consumer Electronics Suppliers Association; Department of Health and Human Services, Tas.; Engineers Australia; Facility Management Association of Australia; NSW Health Department; Plastics and Chemicals Industries Association; Plumbing Industry Commission..
