Access the Code of Practice online

This registration will be required once-only per browser/device, which is achieved using a cookie stored on your device.

There is no password required, and your information will not be shared with any third parties.

Please register and accept the terms for the NZMRM online COP
By ticking this box you confirm that you have read and accept the Terms listed below


Disclaimer

Although the information contained in this Code has been obtained from sources believed to be reliable, New Zealand Metal Roofing Manufacturers Inc. makes no warranties or representations of any kind (express or implied) regarding the accuracy, adequacy, currency or completeness of the information, or that it is suitable for the intended use.

Compliance with this Code does not guarantee immunity from breach of any statutory requirements, the New Zealand Building Code or relevant Standards. The final responsibility for the correct design and specification rests with the designer and for its satisfactory execution with the contractor.

While most data have been compiled from case histories, trade experience and testing, small changes in the environment can produce marked differences in performance. The decision to use a particular material, and in what manner, is made at your own risk. The use of a particular material and method may, therefore, need to be modified to its intended end use and environment.

New Zealand Metal Roofing Manufacturers Inc., its directors, officers or employees shall not be responsible for any direct, indirect or special loss or damage arising from, as a consequence of, use of or reliance upon any information contained in this Code.

New Zealand Metal Roofing Manufacturers Inc. expressly disclaims any liability which is based on or arises out of the information or any errors, omissions or misstatements.

If reprinted, reproduced or used in any form, the New Zealand Metal Roofing Manufacturers Inc. (NZMRM) should be acknowledged as the source of information.

You should always refer to the current online Code of Practicefor the most recent updates on information contained in this Code.

Scope

This Code of Practice provides requirements, information and guidelines, to the Building Consent Authorities, the Building Certifier, Specifier, Designer, Licensed Building Practitioner, Trade Trainee, Installer and the end user on the design, installation, performance, and transportation of all metal roof and wall cladding used in New Zealand.

The calculations and the details contained in this Code of Practice provide a means of complying with the performance provisions of the NZBC and the requirements of the Health and Safety at Work Act 2015.

The scope of this document includes all buildings covered by NZS 3604, AS/NZS 1170 and those designed and built under specific engineering design.

It has been written and compiled from proven performance and cites a standard of acceptable practice agreed between manufacturers and roofing contractors.

The drawings and requirements contained in this Code illustrate acceptable trade practice, but recommended or better trade practice is also quoted as being a preferred alternative.

Because the environment and wind categories vary throughout New Zealand, acceptable trade practice must be altered accordingly; in severe environments and high wind design load categories, the requirements of the NZBC will only be met by using specific detailing as described in this Code.

The purpose of this Code of Practice is to present both Acceptable Trade Practice and Recommended Trade Practice, in a user-friendly format to ensure that the roof and wall cladding, flashings, drainage accessories, and fastenings will:

  • comply with the requirements of B1, B2, E1 E2 and E3 of the NZBC;
  • comply with the design loading requirements of AS/NZS 1170 and NZS 3604 and with AS/NZS 1562;
  • have and optimised lifespan; and
  • be weathertight.

COP v24.03:Revision-History; 2019-August

19.18 2019 – August 

The following updates to the NZ Metal Roof and Wall Cladding Code Practice (COP), are effective 1 August 2019.

Major Revisions

  1. The main clause 17.1 Metal Cladding Testing was substantially revised to give more practical guidance for testing in accordance with the NZ MRM Code of Practice.
  2. The main clause 13 Safety has been substantially revised and updated to closer reflect the Health and Safety at Work Act 2015, referencing the documents Worksafe: Working on Roofs and Worksafe: Working at Height in New Zealand.
  3. The sub-clause 14.20A Fixing Aluminium  has been substantially revised to better reflect good trade practice and manufacturers’ recommendations.

Summary of other changes in this update

 

19.18A Revision Detail - 2019 - August

CategoryClause Number (at time of update)Clause (As of current publication)Details
4 - Clause Inserted 19.18 2019 – AugustSummary of Changes – August 2019 
1 - Minor Errata10.510.5 Building AirtightnessMinor erata: changed 36.2  to 3602
0 - Clause Removed9.4Penetration PositioningClause is now included in Penetration Design.
2 - Editing and rearrangement9.59.4 Penetration DesignRevised clause. Penetration Positioning is now included in this clause.
1 - Minor Errata14.814.9 Setting Out Typo correction
4 - Clause Inserted9.69.5 Boot FlashingsChanged the word profile to profiles for consistency with the rest of the document.
4 - Clause Inserted 9.4.2.4 Penetration Flashings ReferenceNew clause to compare penetration flashing options.
2 - Editing and rearrangement9.5.39.4.1.2 Under-Soaker Back FlashingsClause renamed for consistency.
1 - Minor Errata9.5.4.39.4.2.3 Cricket Back CurbsChanged kerb to curb for consistency.
1 - Minor Errata8.38.4 Flashing CoverCorrected a misprint, removed <20mm from aprons, category B.
1 - Minor Errata14.13.414.14.4 Fastener Allowance for ExpansionFixed 8 mm for style consistency.
2 - Editing and rearrangement14.12.114.13.1 NailsPhoto of Nail Pull-Out inserted.
4 - Clause Inserted 14.20.1 Painted AluminiumNewly created clause dealing with Painted Aluminum products
4 - Clause Inserted 14.20.2 Recommendations for Fixing AluminiumNewly created clause setting out COP recommendations for fixing aluminium claddding.
0 - Clause Removed13Site PracticeClause removed. Topics previously discussed in Site Practice is now dealt with in more detail in various clauses under Installation.
3 - Substantial change to recommendation13.113 SafetySafety has been updated in accordance with the Health and Safety at Work Act 2015 (HSWA 2015).
3 - Substantial change to recommendation13.1.113.2 ResponsibilitiesClause updated in accordance with the Health and Safety at Work Act (HSWA) 2015.
3 - Substantial change to recommendation13.1.713.4.1 ScaffoldingClause has been substantially revised in accordance with Worksafe: Working at height in New Zealand.
3 - Substantial change to recommendation13.1.1013.4.3 Safety MeshThis clause has been substantially revised in accordance with Worksafe: Working at Height in New Zealand. 
4 - Clause Inserted 13.4.6 Safety HarnessNew clause.
4 - Clause Inserted 13.4.7 Soft Landing SystemsNew clause.
2 - Editing and rearrangement14.2114.22 Tools Of The TradePicture added: Turn Up and Turn Down Tools.
2 - Editing and rearrangement9.5.29.4.1.1 Over-Flashed (Watershed) Back FlashingsClause has been renamed.
0 - Clause Removed13.1.2TrainingClause removed. Whole main clause (Safety) has been substantially revised in accordance with HSWA 2015 and Worksafe guidelines.
0 - Clause Removed13.1.5Limitations Of Fall Arrest And Travel RestraintClause removed. Whole main clause (Safety) has been substantially revised in accordance with HSWA 2015 and Worksafe guidelines.
0 - Clause Removed13.1.4Residential And Light Commercial RoofingClause removed. Whole main clause (Safety) has been substantially revised in accordance with HSWA 2015 and Worksafe guidelines.
0 - Clause Removed13.1.13Roof Access During ConstructionClause removed. Whole main clause (Safety) has been substantially revised in accordance with HSWA 2015 and Worksafe guidelines.
0 - Clause Removed13.1.12Joining Safety MeshClause removed. Whole main clause (Safety) has been substantially revised in accordance with HSWA 2015 and Worksafe guidelines.
0 - Clause Removed13.1.11Steel FixingClause removed. Whole main clause (Safety) has been substantially revised in accordance with HSWA 2015 and Worksafe guidelines.
0 - Clause Removed13.1.9Personal SafetyClause removed. Whole main clause (Safety) has been substantially revised in accordance with HSWA 2015 and Worksafe guidelines.
0 - Clause Removed13.1.8Mobile ScaffoldsClause removed. Whole main clause (Safety) has been substantially revised in accordance with HSWA 2015 and Worksafe guidelines.
0 - Clause Removed13.1.6AccessClause removed. Whole main clause (Safety) has been substantially revised in accordance with HSWA 2015 and Worksafe guidelines.
4 - Clause Inserted 13.4.5 Mechanical Access PlantNew clause.
4 - Clause Inserted 13.4.4 Safety NettingNew clause.
4 - Clause Inserted 13.3.3 Weather ConditionsNew clause.
4 - Clause Inserted 13.3.2 Assessment of Existing Roof CladdingNew clause.
4 - Clause Inserted 13.3.1 Safe Access to RoofsNew clause.
4 - Clause Inserted 13.3 Working on RoofsNew clause.
4 - Clause Inserted 13.2.4.1 Other People's ResponsibilitiesNew clause.
4 - Clause Inserted 13.2.4 Other PeopleNew clause.
4 - Clause Inserted 13.2.1 PCBUNew clause.
4 - Clause Inserted 13.2.3.1 Workers' ResponsibilitiesNew clause.
4 - Clause Inserted 13.2.3 WorkersNew clause.
4 - Clause Inserted 13.2.2.1 Officer ResponsibilitiesNew clause.
4 - Clause Inserted 13.2.2 OfficersNew clause.
4 - Clause Inserted 13.2.1.1 PCBU ResponsibilitiesNew clause.
4 - Clause Inserted9.5.59.4.2.5 Penetration Flashings on Corrugated ProfilesThis clause has been revised and renamed to specifically show sheetmetal flashings on corrugated profiles.
4 - Clause Inserted 3.15.4 Standing SeamNew clause.
4 - Clause Inserted 3.4.4 Secret-fixed ProfilesNew clause.
2 - Editing and rearrangement14.3.214.3.2 Wet Storage DamageRemoved reference to "Fretting".
2 - Editing and rearrangement2.12.1 DefinitionsUpdated Glossary item: "Fretting"
2 - Editing and rearrangement4.124.11 Inert CatchmentInserted photo "Localised Damage due to Inert Catchment".
1 - Minor Errata14.414.4 Site SafetyFixed link: Safety
1 - Minor Errata14.514.5 HandlingMinor grammatical fix.
1 - Minor Errata14.7.114.7.1 Storing Product with Strippable FilmGrammar fix.
1 - Minor Errata14.7.214.7.2 Using Strippable FilmGrammar fix.
1 - Minor Errata14.114.11 OverhangDrawing tidy up.
4 - Clause Inserted 17.1 Metal Cladding TestingNew Clause, to replace Testing.
4 - Clause Inserted 17.1.1 Standards: AS Standards and COP Testing StandardNew clause.
4 - Clause Inserted 17.1.2 Test RequirementsNew Clause
4 - Clause Inserted 17.1.2.1 Supporting Structure and EquipmentNew Clause
4 - Clause Inserted 17.1.2.2 Test Set-upNew clause.
4 - Clause Inserted 17.1.2.2.1 Number of SpecimensNew clause.
4 - Clause Inserted 17.1.2.2.2 Width of SpecimenNew clause.
4 - Clause Inserted 17.1.2.2.3 Number of SpansNew clause.
4 - Clause Inserted 17.1.3 Testing ProcedureNew clause.
4 - Clause Inserted 17.1.3.1 UDL TestingNew clause.
4 - Clause Inserted 17.1.5 Publishing ResultsNew clause.
4 - Clause Inserted 17.1.5.1 Allowance for VariationNew clause.
0 - Clause Removed17TestingThe entire clause Testing has been substantially revised and published as Structural Testing to give better guidance on testing according to the Code of Practice Standards.
0 - Clause Removed17.2Background to ScopeThe entire clause Testing has been substantially revised and published as Structural Testing to give better guidance on testing according to the Code of Practice Standards.
0 - Clause Removed17.1ScopeThe entire clause Testing has been substantially revised and published as Structural Testing to give better guidance on testing according to the Code of Practice Standards.
0 - Clause Removed17.3General Methods Of Testing Sheet Roof And Wall CladdingThe entire clause Testing has been substantially revised and published as Structural Testing to give better guidance on testing according to the Code of Practice Standards.
0 - Clause Removed17.4Commentary On 16.3The entire clause Testing has been substantially revised and published as Structural Testing to give better guidance on testing according to the Code of Practice Standards.
0 - Clause Removed17.5Determining Wind load Span GraphsThe entire clause Testing has been substantially revised and published as Structural Testing to give better guidance on testing according to the Code of Practice Standards.
0 - Clause Removed17.6Specific Methods Of Testing Sheet Roof And Wall CladdingThe entire clause Testing has been substantially revised and published as Structural Testing to give better guidance on testing according to the Code of Practice Standards.
0 - Clause Removed17.7Wind and Point Load TestingThe entire clause Testing has been substantially revised and published as Structural Testing to give better guidance on testing according to the Code of Practice Standards.
0 - Clause Removed17.8Method: Resistance To Wind Pressures For New ZealandThe entire clause Testing has been substantially revised and published as Structural Testing to give better guidance on testing according to the Code of Practice Standards.
0 - Clause Removed17.9Background to wind load testingThe entire clause Testing has been substantially revised and published as Structural Testing to give better guidance on testing according to the Code of Practice Standards.
4 - Clause Inserted 17.1.5.3 Interpreting Point Load ResultsNew clause.
4 - Clause Inserted 17.1.3.2 Point Load TestingNew clause.
4 - Clause Inserted 17.1.1.1 UDL Load Testing StandardNew clause.
4 - Clause Inserted 9.4.2.7 Cricket Over-Flashing More Than 1 m WideNew clause.
4 - Clause Inserted 9.4.3 Dormer DetailsNew clause.
4 - Clause Inserted 17.1.1.2 Point Load Testing StandardNew Clause.
1 - Minor Errata14.2.214.2.2 OrderingPunctuation fix.
3 - Substantial change to recommendation13.1.3.113.4.2 Roof Edge ProtectionClause has been substantially revised in accordance with Worksafe: Working at Height in New Zealand.
3 - Substantial change to recommendation13.1.313.4 Working At HeightClause has been substantially revised in accordance with the HSWA 2015.  
4 - Clause Inserted 9.4.2.6 Penetration Flashings on Trapezoidal ProfilesNew clause, specifically showing penetration flashings on trapezoidal profiles.
3 - Substantial change to recommendation14.1914.20 Fixing Aluminium SheetingSection comprehensively revised to better reflect good trade practice and Manufacturer’s recommendations.
2 - Editing and rearrangement3.153.4 ProfilesInserted new Drawing: Profile Types
2 - Editing and rearrangement3.15.23.4.2 Trapezoidal ProfileRemoved drawing in favour of a more descriptive drawing: Profile Types.
4 - Clause Inserted9.5.19.4.1 Penetration Back FlashingsTable removed.
4 - Clause Inserted 17.1.4 Test ReportNew clause.
4 - Clause Inserted 17.1.5.2 Interpreting UDL Load ResultsNew clause.
4 - Clause Inserted 17.1.3.2 Point Load TestingNew clause.