A number of sustainable exotic plantation timbers are grown in New Zealand. Macrocarpa, which is often used as an all-purpose term for cypresses, is one of the most popular interior timbers for its warm golden-brown tone and natural resistance to borer. Lawson’s cypress, a paler cypress, is also popular for a more Scandinavian effect. There are also a huge number of imported wood options. These can usually be sourced as sustainable plantation timber with well-recognised certifications, though they have the obvious drawback of needing to be transported long distances to get here.
Wood panels come in several types – plywood, which is made of very thin sheets of wood glued together to give the sheet strength and warp-resistance, and medium-density fibreboard (MDF), particle board and oriented strand board (OSB), which are made from sawmill waste held together by resins. MDF contains the smallest wood particles, and OSB the largest. Recycling sawmill waste is a positive for the environment; however, the main drawback for these products is that the resins used in them usually contain formaldehyde, a known carcinogen that can off-gas into the environment.
There are some formaldehyde-free products, but most panels carry an emissions rating for the amount of formaldehyde they release. Ask for panels with a rating of E0 or E1, which are the highest standards for indoor air. Check to ensure the product you’re specifying carries a sustainable forestry certification. Some products carry Environmental Choice certifications, but just because one product in a range carries it doesn’t mean all will, so check every product. Choose natural finishes that use plant-based oils, tree resins and waxes.