The following revisions to the NZ Metal Roof and Wall Cladding Code of Practice were published on 1 December 2020.
Summary of Changes in this update:
We introduced three more responsive tools to aid in roof drainage design. They are:
- 7.1.4 Maximum Run Calculator: Calculating the maximum roof length of any profile, at any pitch, and for any rainfall intensity to achieve effective roof drainage.
- 5.8.1 Maximum Area Above Spreader Calculator: To calculate the maximum allowable area feeding into spreaders.
- 9.4.4 Maximum Area Above Penetration Calculator: To calculate the maximum allowable area above roof penetrations.
The rest of this update consisted of fixing minor errors and improvements for clarity.
|Category||Clause Number (at time of update)||Clause (As of current publication)||Details|
|2 - Editing and rearrangement||1||1 Introduction||Update Revisions Message|
|1 - Minor Errata||1.3||1.3 Standards and Related Documents||Clause renamed.|
|1 - Minor Errata||4.10.1||4.9.1 Dissimilar Metals||Formatting fix.|
|1 - Minor Errata||4.10.3||4.9.4 Compatibility Table||Removed reference to Butly Rubber into its own clause 4.9.3 Compatibility with Non-Metallic Substances.|
|2 - Editing and rearrangement||4.12||4.11 Inert Catchment||Inserted photo "Localised Damage due to Inert Catchment".|
|1 - Minor Errata||188.8.131.52||5.5.6 Asymmetrical Valleys||Punctuation fix.|
|2 - Editing and rearrangement||5.2.5||7.1.3 Roof Drainage Capacity||Clause renamed to more accurately reflect its content.|
|4 - Clause Inserted||5.4.3||5.8.1 Maximum Area Above Spreader Calculator||New online tool for calculating maximum drainage areas for spreaders.|
|1 - Minor Errata||5.5||5.4.2 Gutter Capacity Design||Grammar fix.|
|2 - Editing and rearrangement||5.6.3||5.3.2 Rainfall Intensity||Rainfall intensity maps have been added to this clause. Links to rainfall maps have been included in the calculators.|
|1 - Minor Errata||184.108.40.206||220.127.116.11 Allowance for Short-Term Intensities||Updated short-term intensity multiplication factors.|
|2 - Editing and rearrangement||5.7||5.4.7 Gutter Capacity Calculator||Renamed the clause. Other capacity calculators have been moved closer to the relevant information dealing with each topic.|
|0 - Clause Removed||5.7.1||North Island 50-year ARI, 10-minute Rainfall Intensity Map||Map moved to 5.3.2 Rainfall Intensity.|
|0 - Clause Removed||5.7.2||South Island 50-year ARI, 10-minute Rainfall Intensity Map||Map moved to 5.3.2 Rainfall Intensity.|
|3 - Substantial change to recommendation||7.1.2||7.1.2 Runoff||Clause completely revised.|
|4 - Clause Inserted||7.1.3||7.1.4 Maximum Run Calculator||New online tool to calculate maximum run for drainage of different roofing profiles.|
|2 - Editing and rearrangement||18.104.22.168||22.214.171.124 Eaves Flashing||Inserted a paragraph recommending eaves flashings in Marine Environments.|
|1 - Minor Errata||9.4.2||9.4.2 Curb Design||Introductory copy added.|
|4 - Clause Inserted||9.4.4||9.4.4 Maximum Area Above Penetration Calculator||New online tool for calculating the maximum area above a penetration.|
|1 - Minor Errata||126.96.36.199||188.8.131.52 Site Testing||Updated the graph.|
|4 - Clause Inserted||4.9.3 Compatibility with Non-Metallic Substances||A new clause, previously part of "4.10.3 Compatibility Table". Information was split since this is not part of the table or online tool.|
|4 - Clause Inserted||5.5.7 Valley Capacity Calculator||New clause created for Valley Capacity Calculator. The calculator was previously part of Capacity Calculators.|
|4 - Clause Inserted||5.7.3 Downpipe Capacity Calculator||New clause for Downpipe Capacity Calculators.|
|4 - Clause Inserted||19.11 2020 – December||New clause showing updates effective on 1 December 2020.|