Timber (also known as construction timber) is wood that is used as a building material for the construction of buildings and other structures. Depending on the form and degree of processing, a distinction is made between different construction timber products, which are categorised as solid wood, glulam and engineered wood. Various standards define quality requirements and properties that the construction timber products must fulfil, depending on their use. Higher quality classes are sometimes differentiated from construction timber as so-called solid structural timber. The disposal of construction and demolition timber (waste wood disposal) is regulated in the Waste Wood Ordinance.