By the nature of the construction project is working with a normal aberration. In work must be done under the rules it is the contract figure item and other details, according to the agreement.
The nature of the construction work that is normal tolerances. The work is to be done under rules that contract forms and other details of the agreement.
The nature of the construction project is a work with error is normal. Both work to do under the rules, it is a promise, form items and other details according to agreement.