Cost certainty in projects comes from a handful of conversations that happen early, or fail to happen at all, and the difference shows up months later when two sides realize they were never aligned when it came to the cost and pricing. Most of what follows will sound familiar. The hard part isn’t learning it; it’s doing it consistently and trusting the process.
When a collaborative delivery (CMAR, PDB, FPDB) project kicks off, the first move is nailing down scope, generally by dividing the project into a work breakdown structure. Additionally, the project team can start working on the process and the “rules” for how the individual parties will be working toward development and ultimate agreement on the guaranteed maximum price (GMP) or lump-sum price. Even so, cost conversations may not start until three to six months into the contract. That gap is part of why an early baseline or rough order of magnitude estimate can be a benefit (a point covered in more detail below).
Understanding scope and agreeing on the rules go hand in hand—not only what scope of work is required, but how to quantify it. That means agreeing on how cost will be quantified and what it’s based on, labor and equipment rates, and whether rates are monthly or hourly with adjustments. Using the same rate basis before the estimate starts is what makes early numbers comparable. Even though there may be a difference of opinion on the exact number of hours required per construction task, the individual estimating teams need to be using the same rates for comparison purposes or it will be difficult, if not impossible, to compare and reconcile. When there’s disagreement on that basis, the instinct should be to address it immediately rather than letting it surface later.
Here’s an example of what can happen when that doesn’t happen: If both sides aren’t working from the same equipment rates or the same subcontractor and material pricing plugs, alignment doesn’t happen. Each side ends up estimating from a different set of numbers. An electrical scope estimated at roughly $15 million using one basis might come in at $7 million using another—a case where two sides realize they were never pricing the same scope of work. Beyond the number gap, that kind of mismatch breeds mistrust between the parties.
Avoiding a difference in assumptions isn’t complicated. Kickoff meetings should lay out the work breakdown structure, state the rate basis the contract requires, share initial plug rates for subcontractors, and explicitly invite pushback before the estimate moves forward. Numbers can still be adjusted later as more information becomes available. The point is doing it together in an open and transparent manner that reduces the chances of preventable differences surfacing later. Once those assumptions are agreed on, the project needs a way to preserve that alignment as decisions are made and the design evolves. That’s where a shared scope document creates a single, shared understanding of what’s really being priced and gives both sides a working reference they can return to when questions arise later.
If alignment on an assumption is not possible, the difference should be documented and reflected in the estimate. Without that alignment, the client and contractor are evaluating different assumptions, different pricing inputs, and ultimately different versions of the project.
Opening the Estimate
Open book means sharing the thought process behind the estimate and the planned approach for building the job. Understanding a number requires visibility into the assumptions, production rates, crew structures, equipment selections, and construction approach that produced it. An open-book process may seem straightforward and simple in theory, but without alignment on deliverables and the process for evaluating them, uncertainty around project cost grows and friction between the project team follows.
The goal is to walk through the estimate together, including crew sizes, equipment choices, and build approach, so that even if there’s disagreement with a decision, the reasoning behind it is understood.
There’s a second half to open book that often gets overlooked. Rather than disclosure moving one direction, open-book practice must include an openness to hearing the other side as well. One of the biggest challenges in the industry is avoiding the belief that there’s only one right way to do something.
As practitioners we need to help our clients understand that trusting the process is key to achieving cost certainty. This requires both sides to share information in ways they may not be accustomed to, and that takes trust.
Finding Cost Drivers
Ask what causes uncertainty later in a project and many of the largest gaps are found in general conditions and general requirements, the parts of a proposal that don’t get the same attention as design or construction methodology. Bringing counterparts along as decisions evolve helps maintain alignment and strengthens the partnership.
General conditions are especially prone to this because they typically receive less attention early in the process. Teams naturally gravitate toward design and construction means and methods, even though general conditions can significantly impact cost. Inattention has a real cost, and it’s not a small one. General conditions can represent a significant share of total project cost, potentially tens of millions of dollars depending on the size and duration of the job.
Here’s an example that comes up repeatedly: A general condition specification seems insignificant to a client at first glance. But when the specified work is priced out and results in a seven- or eight-figure cost, the reaction is shock and awe. The contractor hears, “How can this cost so much?,” but the application of the requirement as written hasn’t been exactly followed by the other side. Many requirements stem from valid lessons learned. The important thing is understanding the value they provide relative to their cost.
There’s a compounding issue here too. Sometimes one departmental group within an agency will agree that a requirement is unnecessary, only for it to reappear later because another group never signed off on removing it. Alignment on general conditions needs buy-in from other departments within the client’s organization and the end operational users, not just whoever happens to be in the room. The conversation that keeps surfacing, and the one worth building into any early scope discussion, is wants versus needs. Pricing expectations on general conditions often don’t align early on. Reviewing them with a wants-versus-needs lens and putting a number next to what they add up to turns an abstract line item into something a client can weigh directly.
Another item that gets asked early is whether there’s room to deviate from specified mechanical or treatment equipment, and the answer depends heavily on the client. Some clients have a strong preference for a specific brand or system, often tied to familiarity, spare parts, or interchangeability with existing infrastructure, while others are more open to new technology and equipment.
Comfort has a cost. Familiar equipment can simplify operations, maintenance, and spare-parts management, but those benefits may come with a premium. Understanding that tradeoff helps clients make intentional decisions about when consistency and familiarity outweigh opportunities to evaluate alternative solutions.
This creates a tension between cost certainty and innovation. The highest level of cost certainty occurs when the client says, “This is exactly what I want.” The pricing is known, and both parties are estimating the same solution. At the same time, that decision can reduce opportunities to evaluate alternatives that may be lower cost. Exact, predefined outcomes produce highly predictable pricing, while exploring alternatives introduces additional variability and opportunities for savings. It’s up to the project team to discuss this early, find the project’s balance between innovation and predetermined materials and equipment, and realize how this will affect cost certainty.
Those conversations are often more productive when operators are involved early. Rather than starting with makes and models, useful questions are: “What isn’t working today?” and “Where would you like to see improvements?” Answers related to maintenance access, daily operations, spare parts, or reliability often provide the context behind equipment preferences and help distinguish operational requirements from historical habits.
Managing Risk
An early baseline estimate, ideally within 45 to 60 days of contract execution, gives both sides a read on whether pricing is trending toward the available budget. Waiting longer doesn’t create an immediate crisis, but it can affect the realization of any early budget concerns. As schedules and design decisions advance, the ability to pivot becomes more difficult, and that difficulty can become a cost.
The early baseline estimate, or ROM, provides direction by highlighting where costs are concentrated and where additional attention may be needed at the beginning of the process. If the budget is significantly higher than the ROM, that gap is useful information on its own, especially once it’s paired with a sense of where the cost is concentrated. If the budget is significantly lower than the ROM, it provides early insight into where the cost drives may lie.
When developing an early estimate, it can be broken down at a rough level to determine whether a significant portion of the cost is likely tied to materials, labor, equipment, or general conditions. That breakdown tells the contractor and client where costs are concentrated and where effort should be spent reducing them. For example, if materials are likely driving the budget, project teams can focus their efforts there rather than equally across every category. The exercise identifies cost drivers sooner, helping both sides focus as design develops.
Breaking costs into buckets—general conditions, civil, structural, mechanical, and risk—is a valuable exercise for both the contractor and the client. The value in “bucketizing” stops both sides from relitigating every line item when the real gap sits in one or two areas. It also helps identify design areas worth revisiting. If mechanical equipment is three times the amount of the client’s estimate, that’s where attention should be focused first. It makes everything relative.
Contingency is meant to cover genuine uncertainty. Cost certainty depends on alignment between contingency, risk items, and estimating assumptions, which means contingency amounts need to be realistic, not overblown or understated. An overblown or understated placeholder number carries unresolved disagreement into a later stage of the project, often until contingency is needed. Shared contingency raises the stakes further by introducing questions about when the contingency will be used, how it will be managed, and who has authority over it. Without clear agreement on those issues, ambiguity tends to surface as disagreement at the exact moment the money is needed.
Sustaining Certainty
Cost certainty is built through a series of estimating decisions: agreeing on the scope of work, the rate basis before pricing begins, being transparent about how the estimate was built, taking general conditions as seriously as physical scope, being honest about what innovation costs and what comfort costs, running an early baseline estimate before optimism sets the budget, listening to the people who will operate the facility, and treating contingency as a real number tied to actual risk. Together, these decisions create a shared understanding of scope, assumptions, risk, and cost drivers before major design and construction decisions become difficult to change.