The bay method of estimating
The bay method of estimating, is an approach used to estimate, costs, materials amounts, quanitities or volumes where a certain elements are repetitive. The term bay usually refers to a compartment or section of a building that repeats, as such it is often used for buildings that have multiple and similar visible compartments such as factory units, warehouses, garages or transport interchanges.
The quantities of materials and/or labour, and thus costs of a single compartment is calculated by estimating in detail through measurements off drawings or 3D models (in the case of BIM, often using material take-off). Then the single unit value is multiplied by the number of compartments or units to be constructed. The individual compartments, units, rooms, elements or bays of the building should be identical or at least very similar for the estimating method to be accurate.
There are many different types of estimating with the bay method of estimating being just one approach. It is worth noting that, in general traditional approaches to the estimating of building quantities have changed with the introduction of CAD, to 3D CAD and modelling, and through to the employment of Building Information Modelling or BIM.
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