The following revisions to the NZ Metal Roof and Wall Cladding Code of Practice were published on 1 March 2023.
Substantial changes to recommendations:
- 5.4.7 Gutter Capacity Calculator extended to include secret gutters, and gutter fall greater than 1:100.
- New clause 5.2A Roof Drainage Terminology as used in the COP.
- Opinion on small sheds and bay windows that do not require spouting.
- Reviewed table 7.1.1 Minimum Roof Cladding Pitch and added maximum run.
- Added design advice for scuppers in 22.214.171.124 Internal Gutter Design Features
- Added advice for minimising roof noise in 15.4.9 Standing Seam Roofing Wind Loads.
Editing and rearrangement:
- Freeboard for Internal Gutters has been increased to 30mm to align with COP calculator and E1/AS1
- 14.11A Minimum Overhang updated drawing. No change to recommendations.
- 14.17 Turndowns (Drip Forming or Drip Edging) reviewed copy to provide guidance for difficult-to-turn-down profiles, such as deep corrugated profiles.
- 2 Glossary added definitions for freeboard, internal gutters, hidden gutters, secret gutters, and raked spouting.
- Updated illustrations detailing
8.5.3C Stepped Fascia Corrugate Over Barge, 8.5.3B Stepped Fascia Corrugate Under Barge,8.5.3E Stepped Fascia Trapezoidal Over Barge, 8.5.3D Stepped Fascia Trapezoidal Under Barge, 8.5.5H Parapet — Reglet Flashing, Chase Cut, 8.5.5I Parapet — Reglet Flashing, Face Fixed, 8.5.3F Tray Roofing-Wall Connection and 5.5.6A Valley Baffle.
Other changes consisted of small fixes for clarity and grammar.
|Category||Clause Number (at time of update)||Clause (As of current publication)||Details|
|3 - Substantial change to recommendation||5.3.7||5.4.7 Gutter Capacity Calculator||Gutter Capacity Calculator now supports calculation where gutter fall is greater than 1:100, and has an option for Secret Gutters (i.e. where a roof slopes towards a raking wall or barge).|
|3 - Substantial change to recommendation||7.1.1||7.1.1 Minimum Roof Cladding Pitch||Revised and renamed table 7.1.1A Minimum Pitch for Generic Metal Roofing.|
|4 - Clause Inserted||5.2 Roof Drainage Terminology||New clause to clarify COP usage of terminology pertaining to Roof Drainage.|
|4 - Clause Inserted||126.96.36.199 Designing for Climate Change||Newly introduced clause, recommending NIWA's HIRDS-tool.|
|4 - Clause Inserted||188.8.131.52 Bay Windows||New clause discussing drainage for Bay Windows.|
|4 - Clause Inserted||184.108.40.206 Outbuildings||New clause to give guidance on roof drainage for outbuildings.|
|2 - Editing and rearrangement||1||1 Introduction||Updated Revisions Message|
|2 - Editing and rearrangement||2.1||2.1 Definitions||Added definitions for Freeboard, Internal gutter, Hidden gutter, Secret gutter, and Raking Spouting.|
|1 - Minor Errata||3.5.2||3.5.2 Wind Load||Fixed broken link.|
|2 - Editing and rearrangement||220.127.116.11||18.104.22.168 Internal Gutter Design Features||Added clarifying text regarding scuppers.|
|2 - Editing and rearrangement||5.4.6||5.5.6 Asymmetrical Valleys||Included details drawing for installing a .|
|2 - Editing and rearrangement||8.3||8.4 Flashing Cover||Added clarification of rib cover to 8.4K Apron Flashing Cover — Trapezoidal.|
|2 - Editing and rearrangement||8.4.2||8.5.3 Barge And Verge||Added illustrations showing details for:8.5.3B Stepped Fascia Corrugate Under Barge; 8.5.3C Stepped Fascia Corrugate Over Barge; 8.5.3D Stepped Fascia Trapezoidal Under Barge; 8.5.3E Stepped Fascia Trapezoidal Over Barge; and 8.5.3F Tray Roofing-Wall Connection.|
|2 - Editing and rearrangement||8.4.4||8.5.5 Apron Flashings||Added illustration showing 8.5.5H Parapet — Reglet Flashing, Chase Cut and 8.5.5I Parapet — Reglet Flashing, Face Fixed.|
|1 - Minor Errata||14.16||14.16 Stop-ends||Minor edit for clarity.|
|2 - Editing and rearrangement||14.17||14.17 Turndowns (Drip Forming or Drip Edging)||Edited copy to provide guidance for difficult to turn down profiles, such as deep corrugated profiles.|
|4 - Clause Inserted||19.4 2023 – March||Revision and updates active 1 March 2023.|