A timber mill is a factory with power-driven machines that transform logs into lumber. The process consumes energy and produces emissions, but the embodied energy of the raw materials is stored in the finished product, so the process is considered sustainable.
A log is a large branch or trunk of a tree. Typically, it’s felled, then cut into smaller sections, known as fagots, that are transported to the sawmill in lorries or railcars. The logs are then processed into timber products, such as wood panels for walls, fencing and construction materials. At the mill, each log is inspected and processed to achieve maximum yield. This includes debarking and bucking, where logs are cut into boards using equipment such as circular saws and bandsaws.
The size of the fagots and how they are cut determines whether they will be used for construction or for furniture making. Some of the fagots may be used for mulch or pulp. Others might be chipped and used as fuel for kilns that dry timber for use in construction. Others are turned into oriented strand boards (OSB), which is a substitute for plywood. For details on Portsmouth Timber Merchants, contact a site like https://www.timbco.co.uk/
The fagots that aren’t used for construction or OSB are used to make sawdust, which is turned into paper and cardboard, and other items. The mills also recycle scrap timber, a process called edging. The edging removes irregularities from the ends of timber and squares up rough lumber pieces to uniform dimensions.
Once the lumber is prepared for drying, it’s stacked in a kiln, which allows the natural moisture content to evaporate and prevent warping or other damage. The stacked lumber is then inspected and graded for quality. The grading is done visually and mechanically using a series of strength tests. The higher the grade, the stronger and more desirable the timber. As the lumber is kiln dried it’s sorted into boards of different sizes and grades. Some of the sorted timber is destined to be rafters, or roof beams, while some will become utility poles for holding up electrical wires. Poles and rafters are graded for height, diameter and straightness.
Other products produced from the timber include pallets, construction materials and timber frame panelling. The mills also treat the timber to provide fire and rot resistance, if necessary. The harvested timber is then transported to a building site for construction or to another supplier for further treatment.