In New Zealand, Western Red Cedar timber finds versatile applications. Its natural resistance to decay and insects makes it ideal for outdoor projects like decking, fencing, and cladding and, with excellent insulation properties, it’s utilised in doors and windows. The timber’s exceptional durability ensures longevity in the country’s varied climate conditions. It’s also favoured for interior design, crafting furniture, and creating intricate woodwork due to its fine texture and rich colour.
Uses
- Weatherboarding
- Shingles
- Shakes
- External joinery
- Window frames and sashes
Selection Factors
- Corrosive to iron. Stainless steel, copper or silicon bronze fastenings are necessary
- Accepts paint and stains well
- Sanding dust can be an irritant
- Avoid using where water run-off from cladding will be in contact with unpainted galvanised steel, or zinc/aluminium coated steel as it will cause accelerated corrosion
- A relatively light, soft but durable timber. Can be left unpainted.
| Common names | Western red cedar (WRC) |
| Species | Thuja Plicata |
| General description | – Heartwood is pale to dark brown – Sapwood is pale – A non-resinous straight grained, low-density softwood. New Zealand-grown timber is more knotty and coarser grained than imported timber – Softwood |
| Origin | North-west of North America |
| Sustainability | Practically all WRC is imported from Canada or the USA. If a sustainable source is required, certification should be obtained from the supplier. A small amount of good-quality cedar is plantation-grown in New Zealand but needs careful selection |
| Availability | Readily available in a range of sizes |
| Durability & treatment | The heart timber is moderately durable. Sapwood can be treated. New Zealand-grown WRC can be less durable depending on growing conditions and age of trees when felled |
| Drying | Kiln drying usually follows air drying down to 30% MC |
Technical Specs
| Physical Characteristics | ||
|---|---|---|
| Shrinkage | Tangential | 5.0% |
| Radial | 2.4% | |
| Strength group | Unseasoned | S7 |
| Seasoned | SD8 | |
| Density | 360 kg/m3 | |
| Hardness | 1.5 | |
| Durability Class | Highly durable |