Are there special timber treatment requirements for NZ Radiata timber in tropical conditions, especially insect attack?

Use CCA treated timber for termite protection, H2 is for framing timber, H3 (not H3.2) for above ground exterior and H4 or H5 for ground contact.

Australian standards are usually applied with regards to dealing with termites in the Pacific Islands.

AS 1604.1 for sawn and round timber, AS/NZS 1604.2 – AS/NZS 1604.5 for reconstituted wood products, plywood, LVL and glue laminated products.

These standards would meet or exceed likely requirements in tropical areas where termites are a hazard.

Standards New Zealand: Timber Treatment –