Material take off

Material Take Off (MTO) is a term used in engineering and construction, and refers to a list of materials with quantities and types (such as specific grades of steel) that are required to build a designed structure or item. This list is generated by analysis of a blueprint or other design document. The list of required materials for construction is sometimes referred to as the Material Take Off List (MTOL).

Material take off is not limited to the amount of required material, but also the weight of the items taken off. This is an important factor when dealing with larger structures, allowing the company that does the take off to determine total weight of the item and how best to move the item (if necessary) when construction is completed.

Definition used by the ISA (Instrument Society of America):
A Material Take Off (MTO) is the process of analyzing the drawings and determining all the materials required to accomplish the design. We then use the material takeoff to create a bill of materials (BOM). Inspection does not aid in creating a bill of materials. Procurement and requisition are activities that occur after the bill of materials is complete.
Reference: Whitt, Successful Instrument and Control System Design, ISA Press, 2004.