Recycled and alternative materials currently allowed on Transport Agency projects
The list below of surface and pavement standards outlines the recycled materials currently allowed on Transport Agency projects. The list also provides limitations by volume of mass and relevant comments with regards to the material use.
Overview of recycled materials allowed by the NZ Transport Agency
M3 - Sub-base aggregateM3 - Sub-base aggregate
| Material type | Allowed | % by mass | Comment |
| Various | Yes | No restriction | There is no standard TNZ/M3, as the variety of materials satisfactory for sub-bases is too wide to set a national or regional standard specification. TNZ/M3, however, provides guidance on developing a local specification for sub-base aggregates. Generally, there is no upper limit for recycled material content. Local specification using recycled material other than glass will need to be approved by the appropriate regional council. |
M4 - Basecourse aggregateM4 - Basecourse aggregate
| Material type | Allowed | % by mass | Comment |
| Recycled crushed concrete (RCC) | Yes | No restriction | RCC use must be approved by the appropriate regional council. |
| Glenbrook melter slag | Yes | No restriction | Slag use must be approved by the appropriate regional council. |
| Reclaimed glass | Yes | 5% | Proportions of cullet in excess of 5% may be used at the discretion of the NZ Transport Agency National Pavements Manager, provided that the requirements of the T/15 specification have been satisfied. |
M6 - Sealing chipM6 - Sealing chip
| Material type | Allowed | % by mass | Comment |
| Glenbrook melter slag | Yes | No restriction |
M10 - Dense graded stone mastic asphaltM10 - Dense graded stone mastic asphalt
| Material type | Allowed | % by mass | Comment |
| Recycled asphalt pavement (RAP) | Yes | <15% | No restrictions. |
| 15% - 30% | Needs to meet mixed design requirements. | ||
| >30% | Requires approval of the NZ Transport Agency National Pavements Manager. | ||
| Coarse recycled aggregate material | Yes | No restriction | Subject to the engineer's approval (includes slag or glass, or other materials approved by the engineer). |
For further information contact environment@nzta.govt.nz .