# Mechanical Estimating and Costing

Mechanical estimators create budgets for projects in a variety of industries. They must have strong budgeting skills to prepare accurate estimates that meet deadlines. They may also need to travel to job sites to complete onsite measurements.

Unit Price and Schedule Estimating breaks a project into small increments of work and determines the cost of each piece of work. Then these costs are added together to find the total estimate.

## Cost Analysis

Cost analysis is a key part of the mechanical engineering and plant construction process. It helps ensure that products are delivered at an appropriate price to satisfy customer requirements, while simultaneously allowing companies to analyze, control and optimize costs continuously. Cost calculations must be flexible, accurate and reliable to support the variety of product variants that may be required.

An effective cost estimate depends on the type of project being analyzed and its status in the acquisition cycle. The four major analytical methods used to develop cost estimates include Analogy, Parametric (Statistical), Engineering (Bottoms Up) and Actual Costs.

In analogous estimating, unit costs are estimated using historical data for an analogous system or subsystem. This method is relatively easy to use but tends to be less accurate than parametric estimating. In the Engineering Estimate technique, a system is broken down into lower-level components and each is costed using engineering development models or actual costs. This is the most comprehensive approach but can be time consuming and difficult to manage.

In parametric estimating, unit costs are estimated by developing regression or statistical models that link inputs (such as labor and materials) to outputs (project completion times). The resulting model yields an expected unit cost for each of the system components, with the total project cost based on the sum of these unit costs.

## Market Analysis

Efficient estimating techniques are required to ensure construction projects can be completed on time and within budget. This is especially important in the case of complex projects where the scope of work is not well understood. Hence, it is essential to understand different cost estimation methods and choose the right one for your project.

The choice of an estimating technique should be based on what the company wants to achieve from the study. For example, the study may be designed to support a price discussion with a customer or provide information that will assist in planning future projects. The price of the study should also be based on its ability to deliver these business results.

Some of the most important estimating techniques include the use of commercial unit price data and a project comparison approach. The latter relies on a database that contains the costs of previous project types with similar scope and characteristics. The result is an estimate of the cost of a new project that can be compared to the cost of similar previous projects.

Other estimating methodologies include the use of empirical estimation and regression analysis. Empirical estimation uses statistical techniques to estimate the best parameter values for an assumed cost function. Typically, this is done by finding a correlation between the size of the project and its construction cost. This method is a good fit for the early design phase when it can be used to calculate an interim estimate from quantity takeoffs.

## Site Analysis

The site analysis process is one of the most important aspects of mechanical estimating and costing. In fact, it can save architects and builders significant time and money in the long run. It also helps them avoid costly mistakes. In order to make the most of this process, it’s important to understand what it involves and how it works.

The initial site analysis involves looking at a number of different factors, including location, type of land, weather conditions and availability of utilities. It can help determine whether a project will be financially viable and identify potential problems that can affect the final design. This will allow the architects to make changes before the work begins, which can prevent a lot of headaches down the road.

Once the initial site analysis is complete, it’s time to start working on a pre-bid estimate. This will typically include the CSI MasterFormat design stage estimating methodologies and be organized using WBS quantities. Ideally, this will be ready for bidding as soon as the design drawings are at least 10% complete.

The engineer’s estimate is based on a list of items and quantities from which the total construction cost is determined. It may be prepared by a professional estimating firm as part of the design team or on behalf of the owner. Common estimating software programs include R.S. Means, Micro Computer-Aided Cost Engineering Systems (MCACES) and SUCCESS Estimator.

## Scheduling

As a mechanical estimator, you will work with the project manager and the project engineer to develop cost estimates for mechanical systems for new construction and renovation projects. You will also be responsible for creating a schedule and budget for the entire project. This process requires strong knowledge of mechanical systems, construction methods and materials.

In the scheduling process, you will develop a critical path schedule and identify the activities that are essential to the project completion. You will then prepare a schedule based on the availability of resources, such as workers and equipment. The schedule will be updated as the project progresses to ensure that it stays within budget. You will also use a schedule analysis technique to examine the possible float in the project’s duration and to identify any activities that can be delayed.

Mechanical estimators will also prepare activity cost estimates, which include the direct costs of constructing the project and indirect costs. These include the costs of planning, investigation, studies and design; land or right-of-way acquisition; and administrative and quality control functions.

There are various methodologies for estimating costs in the early design stages of a project, including order-of-magnitude estimates, parametric estimating and analogous estimating. These estimates will become more accurate as the design process continues. Other popular methods for estimating the cost of a facility at an early stage are to compare it with similar facilities using project benchmarking, factor estimating or by cost modeling.