tags: #publish
links: [[Property Resources]], [[Gardening and Landscaping Resources]]
created: 2020-09-23 Wed
---
# Arsenic-treated timber - Copper Chrome Arsenate (CCA)
- Used to be used for weatherproofing exterior timber
- Must not drill, sand or burn
- Not really a risk of leaching into soil
- Somewhat termite and borer resistant
- No longer permitted for residential uses in Australia, but don't have to replace existing uses. Not actually restricted in NZ
It's no longer considered suitable for water-/flood-exposed uses anyway: from a flood assessment document in a DA:
> **Ancillary Structures (steps, pergolas etc)**: Suitable water-tolerant materials, such as masonry sealed hardwood and corrosive resistant materials, should be used. Copper Chrome Arsenate (CCA) treated timber is not suitable material.