Softwood or Hardwood Timber?
Wood has two classifications: softwood and hardwood. Softwood is (unsurprisingly) softer and grows faster, thus more sustainable and much less expensive than hardwood. The Pine we use is pressure-treated to resist insect damage (borer etc.), whereas Macrocarpa is naturally borer resistant. Hardwood on the other hand is more expensive, but will withstand the elements and resist insects and decay much better.
Softwood - Density
- Radiata Pine (New Zealand) = 500 kg/m3
- Macrocarpa (New Zealand) = 550 kg/m3
Hardwood - Density Vitex (Solomon Islands) = 800 kg/m3
- Kwila (Indonesia) = 870kg/m3
What is Treated Pine Timber?
Treated Pine is a process when Radiata Pine is pressure-treated to resist decay, bora and fungi. This process requires the timber to be fully saturated to insure adequate treatment of the whole board. While it will remain in good structural condition for many years, the initial green colour will fade and the surface will grey over time.
Harmful effects of Weathering on Wooden Outdoor Furniture
Over time, the natural colour of all wooden outdoor furniture naturally weathers to a soft, silver grey when left exposed to the elements. This process takes 6-12 months (depending on your specific climate and how much the furniture is exposed to the elements). The natural imperfections that are inherent features of natural wooden furniture become more pronounced over time, giving a rich, natural and warm appearance.
Expansion and contraction of timbers will occur with changes in humidity and temperature. This can cause timber to split which is natural and not considered a fault. In humid/wet/subtropical climates the timber will likely expand and contract more often, thus causing the grain to rise, split, check or crack. This is a part of the weathering process for outdoor wood furniture. It will not affect the durability of your furniture.
To help prolong the life and protect your wooden furniture, regular maintenance and cleaning is recommended.
- Placement: Select a location for your wooden outdoor furniture (especially unfinished pine) that is away from direct sunlight and heat sources. Unfinished pine is susceptible to cracking and shrinking when exposed to extreme heat or extreme variations of temperature and moisture. It is ideal to place your unfinished pine furniture where environmental conditions are moderate and stable. Consider sealing the feet of items that often sit in damp/wet conditions.
- Cleaning: Regularly clean your wooden outdoor furniture to avoid decay. Do not use a pressure cleaner / water blaster which can strip out the softer wood fibres and protective oils in the timber.
- Protection: Apply a protective wood oil with a clean cloth at least twice a year, it will likely require oiling more often in summer, should the timber appear to be drying out (Consult the documentation provided with your chosen protective coating for more information.)
- Storage: To prolong the life of your furniture, store in a cool, dry location when not in use or during periods of extreme weather. Furniture Covers do stop harmful UV rays and protect from rain, however they also create a sauna like environment for the furniture.
Breathable protective oil coatings are often regarded as the best approach to protecting wooden furniture, as the oil prevents moisture from being absorbed through the pores whilst allowing the grain of the wood to breathe naturally.
Wood preservative oils are varied, from natural to synthetic to hybrid formulas, from clear to tinted colour tones, with or without anti fungi pesticides and/or insect repellents. However, remember that first and fore mostly you should be after a high-performance moisture repellent that coats and treats the wood and is absorbed rather than smothering or skinning on the surface.
Wood stains are applied to give the desired appearance rather than to prolong the lifespan of the timber. If the timber seems wet, it is essential to leave the wood to dry before applying a stained finish.
Paint and varnishes will protect from the elements, but may crack/blister over time and often cause the wooden furniture to have a dead/plastic/non-natural look.
Always consult the documentation provided with your chosen protective coating for more information.