The estimator should have knowledge of works, labor, reliability, and possible faults, and his cost statements must be based on _______.

Purpose of the Estimate

• Construction estimating is the process of forecasting a project’s costs. However, true project costs are only known once the project is completed.
• Accurate estimating is the foundation of profitable contracting. Accuracy must be based on several factors.
• A good estimate prevents the contractor from losing money and helps the customer avoid overpaying.
• A good estimator should have knowledge of works, labor, reliability, and possible faults, and his cost statements must be based on reliable evidence.

​The key factors that make up a successful estimate are:

1.) Selection of materials

 Residential, commercial, and industrial projects require uniquely different materials. A receptacle designed for a residential home cannot be installed in an industrial hazardous location, and the cost difference between these two types of receptacles can reach several thousand dollars.

2.) Required quantity of material

Accuracy is key to the estimating process. Quality detailed installation drawings should provide the estimator with the ability to determine accurate quantities of materials required for the project.

3.) Material pricing at the market level

The contract technical specifications provide the product manufacturers and model numbers for materials to be installed. It is paramount that the specified materials are installed as outlined in the documents. Substituting specified materials with non-specified products can be costly to the contractor. 

4.) Labor requirement

The estimator must have a full understanding of labor units. Each item required to build a project has an associated labor unit. Labor units require adjustment due to the conditions of installation.

5.) Equipment, tools, and consumables

Equipment such as lifts, generators and trenching machines must be included in rental costs if you do not own the equipment. Consumables are materials and tools that the estimator doesn’t include in his take-off. These items are difficult to quantify. Consumables are real project costs and should be included in the estimate.