While the terms "timber vs lumber" may be synonymous in some cases, they have different meanings, which depend on the region. Basically, timber is considered wood in a natural form or wood only partially prepared. Lumber is a piece of wood prepared for further use.

In the United States, the term “lumber” means boards and planks used in construction for building, framing, floors, and furniture. The term “timber” may refer to trees ready for harvesting or large wood pieces. In the UK and some other countries, the term “timber” is used for describing processed wood that is used for constructing buildings. Timber and lumber are important materials for constructions, carpentry, furniture-making, etc. They have to be selected taking into account various criteria like project, size, strength, appearance, and terminology of the region. Understanding the difference between "timber vs lumber" will help to choose a proper wood product.