If a designer understands where raw materials come from, they can understand the environmental concerns associated with that material.
In the context of timber and man-made boards, the original source is a tree. Trees are grown all over the world - some are for timber produce, and others could be for paper. They can be categorised as hardwood and softwood.
Hardwood is harvested from deciduous trees. These types of tree lose their leaves in autumn and take a long time to grow, around 60 years (sometimes up to 100). Hardwoods include beech, oak, mahogany, balsa and jelutong.
Softwood is harvested from coniferous trees. These trees remain evergreen all year and take around half the time to grow, 25 to 30 years. Softwoods include Scots pint, Western red cedar and paraná pine. As trees are felled, it is important to plant new ones so that the timber source is sustainable.
Manufactured boards are made from particles and fibres of natural timbers that are bonded together using resin to form sheets. Manufactured boards often make use of waste wood materials and inlcude plywood, medium-density fibreboard (MDF), chipboard and hardboard.
Once a tree has been chopped down, the branches are removed, so only the trunk of the tree remains. The full length of a tree might be too long to transport and work with, so the tree may be cut to a more manageable length. The tree trunks are transported to a sawmill, where the trees are cut to usable planks. This process is known as conversion.
At this point the timber can be sold. If the timber has been freshly cut, it is sold as ‘green’ timber due to the high water content. If the timber has been dried out before being sold, then it has been ‘seasoned’. Some seasoning can be done by leaving it to ‘air season’, and sometimes the timber is ‘kiln seasoned’.
Plywood is made by gluing at least three layers of sheet timber together at right angles to each other - this is called laminating. Plywood is considered to be a strong board as the grain of the timber sheets are glued together in different directions.