Stonemark Logo Building Confidence

Construction Estimator vs. Project Manager: Do You Know the Difference?

In this article, we will discuss and compare the functions of construction project estimators and project managers. Both are equally vital to the construction process and their employer. Both handle budgets and risks. Sometimes, their duties align and even merge.

Yet, there are many unique distinctions between these roles. Read on to find out more!

What does a construction estimator do?

Estimators price building projects based on drawings and specifications. The way they perform this task differs based on where they work. Those with a General Contractor (GC) will price a wide range of items on a higher level, while those employed by a Subcontractor will mainly focus on their specific trade. While developers, engineers and design professionals and other entities routinely employ estimators, we will focus on their work with builders in this post.

Estimating for a General Contractor

A GC’s estimator strives to draw up an overall estimate for the building. This master estimate includes separate trade line items that eventually include quotes from subcontractors, as well as the GC’s general conditions and requirements, overhead and fee. It’s this estimate that the owner will get during bidding, use to pick the GC, and base their project’s budget. The project’s delivery method usually guides the approach to getting prices for various scopes of work.

1. Lump-sum pricing

Most traditional design-bid-build construction contracts follow lump sum pricing. Here, the GC’s estimator sends out the drawing package to the subcontractors bidding on the job. The subcontractors price the drawings and return a lump sum quote for their portion of the work. Meanwhile, the GC’s estimator typically prepares a control estimate to accumulate all of the costs. With all subcontractors bids received, the GC plugs their numbers into the master estimate, includes their own GC costs and submits their proposal for the entire project.

2. Unit rate pricing

Design-build projects are quite different. Their design evolves as the GC works on the estimate. This parallel flow allows the design to be tweaked to fall in line with quality and budget expectations. To facilitate design decisions, one must know more general unit rates for the supply and installation of various building components. To this end, the estimating team requests unit rate quotes from subcontractors, rather than a lump sum quotation.

While unit rates are instrumental to a budget-conscious design, they’re also less precise than lump-sum quotes, are typically a bit inflated and are more subject to change. This “padding” by subcontractors is meant to offset future design changes that may leave their quotes short of the actual construction costs.

On complex projects, GCs may merge the senior estimator and risk manager roles. When the design-build delivery method is used, a GC may also appoint a senior estimator to liaise with the design team.

Estimating for a Subcontractor

While a GC’s estimator needs the trades’ quotes to build their estimate, the subs’ estimators do the real number-crunching. Whether they’re working on a lump sum or a unit rate project, they must measure quantities and price the required materials, labor, and equipment. The process is typically more detailed than that of their GC peers on the trade level, while on the GC level the emphasis is on including all potential costs and line items.  Many GC estimates for large projects are hundreds of pages long.

What are a project manager’s duties?

Where an estimator is most concerned with a project’s direct and indirect costs, the project manager answers for its delivery and oversees the entire process from conception to close. A project manager’s duties closely mirror the project cycle. Let’s take a look at the tasks these professionals take on during each project phase.

1. Concept

During the concept phase, feasibility is a critical variable in deciding if a project should proceed. Some clients may conduct this study internally or outsource it to a project management firm. In either event, a project manager may perform various assessments to determine if building the project is constructable and economically viable.

2. Planning

This is a remarkably busy time for the project manager. The project manager must come up with:

  • the project plan
  • the resource plan
  • the financial plan
  • the scheduling plan
  • the quality management plan
  • the risk plan
  • the communications plan

With these plans in place, the project is all set for the next, equally busy phase: execution.

Note that planning is also the estimator’s time to shine: this is when their efforts gradually become the financial baseline for construction.

3. Construction Execution

This is where those plans from the previous stage get carried out. The project manager must ensure the delivery of the “product,” i.e., the building, to the customer. During the execution phase, the project manager sets goals, manages the project staff, drafts contracts, and creates the baseline schedule.

Again, GCs on design-build or CM projects may employ estimators during execution to award subcontracts.

4. Monitoring and control

Although it’s sometimes viewed as a separate step, the monitoring and control phase takes place during construction execution. In this stage, the project manager ensures the quality of work and strives to keep construction on time and budget. Their job involves tracking construction progress and managing changes.

5. Project close

With construction finished, the project manager must ensure that:

Post-close, the project manager typically oversees the proper filing of all pertinent documents, produce a final project report, and chair a lessons-learned session with the team.


Estimators and project managers play integral roles in building projects. The former forecast costs, the latter oversees planning and construction. Their paths cross when a project’s budget and risk register are involved, when their duties may align and even interchange. That said, project managers see the project from start to finish, whereas estimators are most active during planning and later in execution.

Share this: Share on Facebook Share on Linked In Share on Google Plus Share on Twitter
What is Construction Management?
What is Construction Management?

Professional construction project management is a super fine-tuned system designed to facilitate planning, coordination and control of a project from the early stages all the way to project closeout and completion. Qualified construction managers use specialized project [...]

read more
Top 10 Benefits of Professional Construction Management
Top 10 Benefits of Professional Construction Management

Thе bеnеfitѕ of professional соnѕtruсtiоn mаnаgеment include highly skilled рrосеѕѕes that facilitate рlаnning, сооrdinаtiоn аnd соntrоl of a project frоm inсерtiоn tо соmрlеtiоn. A professional construction manager will balance the competing needs оf соѕt, ѕсоре аnd [...]

read more
Popular Blog Posts
Connect With Us