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 5.4.5.1 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.
19.7A Revision Detail - 2023 - March
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 | 5.3.2.1 Designing for Climate Change | Newly introduced clause, recommending NIWA's HIRDS-tool. | |
4 - Clause Inserted | 5.4.1.1 Bay Windows | New clause discussing drainage for Bay Windows. | |
4 - Clause Inserted | 5.4.1.2 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 | 5.3.5.1 | 5.4.5.1 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 | 19.7 2023 – March | Revision and updates active 1 March 2023. |