Code of Practice v3.0 Online
The NZ Metal Roof and Wall Cladding Code of Practice is a comprehensive design & installation guide, and a recognised related document for Acceptable Solution E2/AS1 of the NZ Building Code.
The following updates to the NZ Metal Roof and Wall Cladding Code Practice (COP), are effective 1 December 2019.
Major Revisions
- For this update, the COP section 5 Roof Drainage and all its sub-clauses have been substantially revised. The updates focussed heavily on creating new online tools for calculating Roof Drainage, Gutter Capacity, Downpipe Capacity and Valley Capacity, which are located in 5.4.7 Gutter Capacity Calculator.
Summary of other changes in this update
- All the content in 5 Roof Drainage has been updated to provide clarity and brevity, and detail drawings are updated.
- The previous methods of capacity calculations, using two distinct methods based on standard sizes, have been removed and replaced by online calculator in 5.4.7 Gutter Capacity Calculator.
- New clauses have been added for 17.1.3.2 Point Load Testing and 17.1.1.2 Point Load Testing Standard under 17.1 Metal Cladding Testing.
- The Glossary has been updated with 2.1A Definitions for Swiss Gable, Finial, and Profiled Washer; and some minor edits to refine definitions and grammar fixes.
19.13A Revision Detail - 2019 - December
| Category | Clause Number (at time of update) | Clause (As of current publication) | Details |
|---|---|---|---|
| 2 - Editing and rearrangement | 1 | 1 Introduction | Update Revisions Message |
| 2 - Editing and rearrangement | 2.1 | 2.1 Definitions | Revised definition of "Load Spreading Washer", added a new item "Profiled Washer", added definition for "Finial", minor grammatical fixes. |
| 2 - Editing and rearrangement | 5 | 5 Roof Drainage | The entire Roof Drainage-clause had been revised. |
| 1 - Minor Errata | 5.1 | 5.1 NZBC: Clause E1 — Surface Water | Formatting |
| 4 - Clause Inserted | 5.4 Gutters | New clause. | |
| 4 - Clause Inserted | 5.4.1 External Gutters (Spouting) | New clause. | |
| 2 - Editing and rearrangement | 5.5.5 | 5.4.4 Concealed Fascia Gutters | This clause had been completely revised and renamed. |
| 2 - Editing and rearrangement | 5.5.4 | 5.4.5 Internal Gutters | Clause completely revised. |
| 4 - Clause Inserted | 5.4.5.1 Internal Gutter Design Features | New clause. | |
| 2 - Editing and rearrangement | 5.6 | 5.5 Valleys | Valleys had been completely revised and divided into smaller, more specific, sections. |
| 4 - Clause Inserted | 5.5.1 Valley Fixing | New clause. | |
| 4 - Clause Inserted | 5.5.2 Valley Design | New clause. | |
| 4 - Clause Inserted | 5.4.3 Internal Corners | New clause. | |
| 2 - Editing and rearrangement | 5.6.2 | 5.5.3 Bifurcated Valleys | The clause had been revised. Valleys are now discussed in smaller, more specific, clauses. |
| 4 - Clause Inserted | 5.5.5 Changing Angles in Valleys | New clause. | |
| 4 - Clause Inserted | 5.5.6 Asymmetrical Valleys | New clause. | |
| 4 - Clause Inserted | 7.1.3 Roof Drainage Capacity | New clause. | |
| 3 - Substantial change to recommendation | 5.5.7 | 5.4.6 Secret Gutters | Clause revised, for brevity and clarity. |
| 4 - Clause Inserted | 5.6 Rainwater Heads, Sumps, and Overflows | New clause. | |
| 2 - Editing and rearrangement | 5.8.1 | 5.6.1 Rainwater Heads | Clause revised, now providing more information. |
| 2 - Editing and rearrangement | 5.8 | 5.6.2 Sumps | This clause has been revised. |
| 2 - Editing and rearrangement | 5.8.2 | 5.6.3 Overflows | Clause renamed, Outlets are now discussed under Outlets and Downpipes. |
| 4 - Clause Inserted | 5.7 Outlets and Downpipes | New clause. | |
| 4 - Clause Inserted | 5.7.1 Placement of Downpipes | New clause. | |
| 4 - Clause Inserted | 5.7.2 Capacity Table for Common Size Downpipes | New clause. | |
| 2 - Editing and rearrangement | 5.5.1 | 5.4.2 Gutter Capacity Design | Clause has been revised and edited. |
| 4 - Clause Inserted | 5.4.2.2 Maximum Gutter Length | New clause. | |
| 2 - Editing and rearrangement | 5.5.2 | 5.4.2.3 Gutter Support Systems | Clause revised. |
| 4 - Clause Inserted | 14.18.9 Gutter Installation | New clause. | |
| 2 - Editing and rearrangement | 5.2 | 5.3 Roof Drainage Design | Clause had been completely revised. |
| 2 - Editing and rearrangement | 5.3.1 | 5.3.1 Catchment Area | Caluse has been completely revised. All calculations are now under a new clause Capacity Calculations. |
| 2 - Editing and rearrangement | 5.5.8 | 5.4.2.1 Gutter Fall | Clause revised and renamed. |
| 3 - Substantial change to recommendation | 5.3 | 5.3.2 Rainfall Intensity | Clause had been completely revised, with updated Rainfall Intensity Maps at the end of the main Clause, Roof Drainage. |
| 4 - Clause Inserted | 5.3.2.3 Allowance for Short-Term Intensities | New clause. | |
| 4 - Clause Inserted | 5.3.2.2 Duration | New clause | |
| 2 - Editing and rearrangement | 5.3.2 | 5.4.7 Gutter Capacity Calculator | The old clause, Capacity Calculations, replaced by a new clause of the same name but including new online tools. |
| 4 - Clause Inserted | 5.7.1 North Island 50-year ARI, 10-minute Rainfall Intensity Map | New clause. | |
| 4 - Clause Inserted | 5.7.2 South Island 50-year ARI, 10-minute Rainfall Intensity Map | New clause. | |
| 4 - Clause Inserted | 8.3 | 8.3 Flashing Cover | Adjusted spacing in Table 8.3A |
| 2 - Editing and rearrangement | 8.4.4.3 | 8.4.4.3 Step Apron | Removed reference to "Fortress Fasteners" in drawing A: Step Apron Details. |
| 4 - Clause Inserted | 8.4.4.4 | 8.4.4.4 Eaves Flashing | Drawing 8.4.4.4A renamed to Gutter Flashing. |
| 2 - Editing and rearrangement | 12.2 | 12.2 Purlin Creasing | Inserted photograph. |
| 4 - Clause Inserted | 17.1.2 | 17.1.1.2 Point Load Testing Standard | New Clause. |
| 4 - Clause Inserted | 17.3.2 | 17.1.3.2 Point Load Testing | New clause. |
| 1 - Minor Errata | 18.8 | 18.8 Sheet Metal Work For Roofing Contractors. | Clause revised for gender neutrality. No significant changes. |
| 4 - Clause Inserted | 19.13 2019 – December | Summary of Changes – December 2019 | |
| 0 - Clause Removed | 5.3.2.1 | Method 1: Gutter and Downpipe Capacity Determined by Graph | These methods have been replaced by online capacity calculating tools. |
| 0 - Clause Removed | 5.3.2.3 | Method 2: Gutter and Downpipe Capacity Determined by Calculations | These methods have been replaced by online capacity calculating tools. |
| 0 - Clause Removed | 5.3.3 | Roof Cladding Capacity | These methods have been replaced by online capacity calculating tools. |
| 0 - Clause Removed | 5.4 | Snow | Clause removed, Snow and hail are comprehensively discussed in Snow Loads. |
| 0 - Clause Removed | 5.4.1 | Hail | Clause removed. Leaf guards and maintenance are discussed under Gutter Maintenance. |
| 0 - Clause Removed | 5.5 | Gutters | The clause had been removed. Gutters are now discussed in more detail in a separate clause for each type, under the main clause Types of Gutter. |
| 0 - Clause Removed | 5.5.3 | Eaves Gutters | Clause deleted. Now discussed under External Gutters. |
| 0 - Clause Removed | 5.6.1 | Valley Catchment | This clause had been replaced with the newly developed online tool in Valley Capacity Calculations. |
| 0 - Clause Removed | 5.7 | Downpipes | Information previously contained in this clause is now discussed in Outlets and Downpipes. |
| Out-of-band updates 16/12/2019 | |||
| 2 - Editing and rearrangement | 5.4.2A | 5.7.2 Capacity Table for Common Size Downpipes | Removed obsolete column for Roof Area Drained as the online calculator replaces this. |
| 2 - Editing and rearrangement | 5.7 | 5.4.7 Gutter Capacity Calculator | Added link to Common Sized Downpipes. |