Frequently Asked Questions

What species of timber is predominantly produced in New Zealand?

Radiata pine comprises more than 90% of the volume of timber produced in NZ. It is followed by Douglas fir which accounts for about 4%.  Almost all the commercially produced timber in New Zealand is grown from plantation forests that are managed in a sustainable manner to ensure that forestry will continue to be available for generations to come.

What are the physical characteristics of New Zealand Radiata pine (NZRP)?

NZRP is a medium-density coniferous species that has undergone substantial development in its characteristics since being first introduced to the country from California, USA, in the 1930’s.  It is a versatile species, with properties that make it ideal for use in construction, millwork and joinery, as well as being preservative treated for resistance to insect and fungal attack in all exposed situations.

What are the strength properties of NZRP that allow its use in construction?

There are a number of different grades with varying structural properties. Please refer to the Website www.verifiedtimber.co.nz for a description of the properties for the various grades.

What properties make NZRP suitable for appearance uses such as in joinery, millwork and furniture?

NZRP has a very even texture and has small differences in density when comparing spring wood and summer wood. This makes it ideal for machining, such as moulding, planing and turning. Comparative tests with other species demonstrate that NZRP is ideal for routing, sanding, finger-jointing, gluing and nail holding.

How does NZRP achieve durability equal to the most naturally durable timber species?

NZRP is not a naturally durable species. However, the sapwood is extremely permeable to wood preservative solutions, making NZRP the most treatable of all species. Total penetration of preservatives ensures that the treated wood can withstand attack by insects and decay in the most extreme hazards.

New Zealand’s timber treatment industry operates at the highest levels of wood preservation quality and verification.  Standard specifications for preservative treatment define degrees of hazard to which the wood will be exposed and appropriate levels of preservative treatment are set to enable the treated wood to resist the defined hazards.

What about painting and staining NZRP?

The even texture of NZRP means that it holds paint and stain to an excellent standard of finish. Oil or water-based stains are accepted to a high level of consistency and evenness, and paint adheres well to a smooth and even finish.

Is NZRP dry and stable?

Extensive research has been conducted into the drying properties of NZRP.  As a result, there is widespread knowledge amongst New Zealand timber producers about kiln drying technology that will achieve the best quality of dry timber for given end uses.  Different drying cycles have been developed for structural timbers, for decorative timbers, and for timbers that are to be remanufactured or machined.

What are the standard sizes of NZRP?

NZRP is sawn to standard dimensions or call sizes. These apply to timber that is sawn and not planed, dressed or dried. Timber that is kiln-dried and planed or dressed are required to meet standard dimensions as in this table (mm);

Standard lengths range from 2.4m to 6.0m in increments of 0.3m, the most common lengths being 4.2m to 6.0m.

What Hazard class does the Timber need to be treated to for protection against Insect and Fungal attack?

Refer to the Hazard Class table on this website and also www.nztpc.co.nz