The necessity of specifications are the following:

(i) The cost of an unit quantity if work is governed by its specification.

(ii) A work is carried out according to its specification and the contractor is paid for the same. Any change in specification changes the tendered rate.

(iii) As the rate of a work is based on specification a contractor can calculate the rates of various items of works in a tender with his procurement rates of materials and labor. Thus tender paper without specifications of works is baseless.

(iv) The necessity of specification is to verify and check the strength of materials of a work involved in a project.

(v) Specification is an essential contract document is required for arbitration or court cases.