SURFACE FIRE PERFORMANCE OF INSULATION IN PLENUMS AND DUCTS  

As a result of the amendments to NZBC C/AS2-AS7, in particular Table 4.1 Surface Finishes there have been some changes to Masterspec insulation sections.

The requirement for acoustic insulation or pipe insulation within an air handling plenum to have a group number has been removed from Table 4.1 in most Acceptable Solutions except for NZBC C/AS2 and AS3.  In this case under NZBC C/AS2 or AS3 only, a Group Number of 3 is still required.  This means that under the Acceptable Solutions a plenum, such as a ceiling space acting as an air plenum, does not require the insulation to have a group number, except for those under NZBC C/AS2 and AS3.

Unlike air plenums, ducts for HVAC systems are still included in Table 4.1 of NZBC C/AS2 to AS7, which states the internal and external duct surface maximum permitted Group Numbers allowed.  For ducts in protected shafts (excluding lift shafts) only the duct internal surface requires a Group Number, to NZBC C/AS2-AS7, 4.17.11 Air Ducts.  Under NZBC C/VM2, Appendix A, A1.4, a duct complying with the fire hazard properties of AS 4254, is deemed to have a Group Number of 1S.

Please note there is a difference between the Acceptable Solutions and the Verification Method VM2.  Using NZBC C/VM2 under Design Scenario (IS), non-combustible materials like some insulation (when tested to AS 1530.1 or ISO 1182) are deemed to have a Group Number 1 or 1S, without the further evaluations of Appendix A.  This means that for designs using VM2, tested, non-combustible insulation can always be considered as Group Number 1 or 1S.  However in the Acceptable Solutions there is no mention of the status of non-combustible insulation, so it would seem that a Group Number test will be required to prove the Group Number, when necessary in the Acceptable Solutions.  A complicated Alternative Solution may be able to combine the two aspects and overcome the issue, if no Group Number testing has been done.

Note:

  • NZBC C/AS1 is not included in the above as it does not have a Table 4.1.
  • Foamed plastics or combustible insulation have other requirements and in most exposed situations must be tested and have a Group Number.

The Masterspec acoustic insulation sections and mechanical duct and pipe insulation sections have now been updated.

NZBC C/AS2 (1 July 2014) Click the image for a larger file


NZBC C/AS3 (1 July 2014)  Click the image for a larger file



  »GOOGLE VERIFIED
  »ENGINEERING TERMS AND CONDITIONS
  »REVISITING OUR HERITAGE
  »FURTHER CHANGES PROPOSED TO NZBC C PROTECTION FROM FIRE
  »REDUCING PARTITION WALL FAILURE IN SEISMIC EVENTS
  »BUILDING CODE UPDATED REFERENCES
  »MEDIUM DENSITY HOUSING RESOURCE PAGE
  »SPECIFICATIONS HOW-TO
  »DETAILED ENGINEERING EVALUATION TOOLS FROM SESOC
  »BIM FOR ALL - DUMMIES OR NOT
  »MASTERSPEC'S PRODUCT RANGE SUPPORTS MULTI-DISCIPLINARY TEAMS
  »SPECIFICATIONS AND CONTRACTS
  »BUILDING ACT 2004 AMENDMENTS
  »SURFACE FIRE PERFORMANCE OF INSULATION IN PLENUMS AND DUCTS
  »CHANGES TO THE BUILDING ACT – HOW DO THEY AFFECT ARCHITECTS, DESIGNERS AND DESIGN/BUILD
  »WHAT IS THE PURPOSE OF A SPECIFICATION???
  »NZBC C PROTECTION FROM FIRE - AMENDMENTS DECEMBER 2013
  »AMENDMENTS TO NZS 4211
  »STRENGTHENING NEW ZEALAND’S STANDARDS SYSTEM – TRANSITION PROJECT
  »2014 INTERNATIONAL BIM REPORT
  »UPDATED GUIDANCE FOR EXEMPT BUILDING WORK
  »TACTILE GROUND SURFACE INDICATORS (TGSIS)
  »STREAMSIDE PROTECTION AND GUIDES TO RESTORATION
  »SEISMIC RESTRAINTS FOR GAS, WATER HEATERS & APPLIANCES
  »CHANGES TO NZBC C PROTECTION FROM FIRE - 1 JULY 2014
  »CHANGES TO H3.1 FOR SOLID TIMBER FRAMING
  »FIRE SAFETY AND DESIGN – FURTHER READING
  »AS 3566.2 WITHDRAWN BY STANDARDS AUSTRALIA BUT IN E2/AS1?
  »AIR CONDITIONING REFRIGERANT SAFETY
  »WHAT IS GOING ON WITH HEALTH & SAFETY?
  »FURTHER WORKED EXAMPLES TO ACCOMPANY THE SEISMIC DESIGN OF RETAINING STRUCTURES GUIDANCE
  »PASSIVE HOUSING – GENERAL DESIGN PRINCIPLES
  »SPECIFYING FIRE BLANKETS
  »DESIGN AND BUILD - REASONS FOR CONSENT DELAYS
  »AS/NZS 2312 SPLIT UP AND AMENDED
  »FIRE PERFORMANCE OF FLOOR COVERINGS LAID OUT
  »CODEMARK CERTIFICATION POPULAR WITH PRODUCT PARTNERS
  »LOW EMISSIVE GLASS COATINGS - SURFACE 2 OR 3 – WHAT SHOULD IT BE?
  »INTERIOR NOISE CONTROL - TRYING TO UNDERSTAND ACOUSTICS
  »MASTERSPEC INTERVIEW: ANDREW MAYNARD
  »DRAINAGE, LAYING OUT THE OPTIONS
  »ELECTRONIC LEAK DETECTION OF MEMBRANES
  »INTERIOR ELEMENTS - BUILDING CODE REQUIREMENTS CHECKLIST
  »NEW GENERIC SECTION 4239 SOFFIT CLADDING
  »SECTIONS CHANGE AS SOME INSULPRO PRODUCTS REBRANDED AS MAMMOTH
  »MASTERSPEC RELEASE 12 NEW SERVICES ENGINEERING WORK SECTIONS.
  »STRUCTURALLY FIXED CAVITY BATTENS
  »CHANGES TO THE LAMINEX GROUP
  »WORK SECTION UPDATES AND DELETIONS FOR JULY 2015
  »ALTERNATIVE TEST METHODS FOR ACHIEVING NZBC C GROUP NUMBERS.
  »CONCRETE SLABS - FREE JOINTS OR SHRINKAGE CONTROL JOINTS???
  »DRAINAGE GENERAL NAME CHANGE
  »ROOF SAFETY MESH - AS/NZS 4389 UPDATED
  »PLUMBING AND DRAINAGE - AS/NZS 3500.1 AND AS/NZS 3500.2 UPDATED
  »NEW BASIC SECTION FOR PLYWOOD AND PARTICLEBOARD FLOORS
  »GREEN BUILDING REQUIREMENTS IN THE RESIDENTIAL SECTOR
  »NEW SECTIONS FOR MASTERSPEC BASIC AND INTERIORS USERS
  »HEAT PUMP WATER HEATERS NOW AN OPTION
  »WELDING GALVANIZED OR THERMAL SPRAYED STEEL
  »MAJOR CHANGES TO THE CARPENTRY BASED SECTIONS IN MASTERSPEC BASIC AND INTERIORS
  »A COLLECTION OF COUNCIL DEVELOPMENT, SUBDIVISION AND ENGINEERING GUIDES
  »NEW NZS 4407 - ONE ROAD AGGREGATE STANDARD TO UNITE THEM ALL
  »PLUGGING INTO ELECTRIC CARS
  »PUTTING MORE INTO 2242 BACKFILLING
  »AS/NZS 3500.4 HEATED WATER SERVICES UPDATED
  »MAJOR CHANGES TO THE CONSTRUCTION CONTRACTS ACT
  »AS/NZS 1668.1 VENTILATION AND AIR-CON FIRE AND SMOKE CONTROL
  »HEALTH AND SAFETY AT WORK ACT 2015 AND THE SPECIFICATION
  »COMPATIBILITY AND ADHESION OF WET SEALS AND SILL TAPES IN WINDOW INSTALLATIONS
  »JMF TIMBER WINDOW AND DOOR JOINERY CAN BE SPECIFIED ON A ‘TEST’ BASIS
  »STEEL STRUCTURES - NZS 3404.1: 1997 VERSES NZS 3404.1: 2009
  »ASBESTOS REMOVAL NEW LICENCE REGIME
  »MBIE PRODUCT ASSURANCE SEMINARS FOR SUPPLIERS/MANUFACTURERS
  »RESIDENTIAL CONSTRUCTION HANDOVER
  »A BIG MONTH OF CHANGES TO STANDARDS
  »INTERNATIONAL BIM OBJECT STANDARD TO BE RELEASED
  »NON-COMPLIANT CONCRETE REINFORCEMENT
  »TIPS FOR SPECIFYING FIXED AUDIENCE SEATING
© 2017 Construction Information Limited
Construction Information Limited Construction Information
Powered by streamSWEET CMS  
Feedback