Change Orders in Construction: A Complete Guide to the Process
Almost no construction project finishes exactly as it was drawn. Site conditions shift, owners change their minds, materials become unavailable, and design documents turn out to have gaps. When any of that happens after a contract is signed, the formal mechanism for adjusting the agreement is the change order. Understanding change orders in construction is essential for anyone who wants to keep a project on schedule, on budget, and out of a dispute.
This guide explains what a change order is, why they happen, the main types, and how a disciplined process protects everyone involved.
What Is a Change Order in Construction?
A change order is a written amendment to the original construction contract that documents a change to the scope of work, the contract price, the project schedule, or some combination of all three. Once signed by the relevant parties, usually the owner and the contractor, it becomes part of the binding agreement.
The key word is "written." A verbal instruction to add an extra wall or upgrade a finish might feel like enough on a busy site, but without documentation it creates exactly the kind of ambiguity that leads to payment disputes and litigation. A change order in construction turns an informal request into an enforceable record of what was agreed, what it costs, and how it affects the completion date.
A complete change order generally captures a description of the change, the reason for it, the cost adjustment, any time extension, and the signatures of the authorized parties. Industry bodies such as FIDIC publish standardized contract frameworks that define how these adjustments, often called variations in international contracts, should be valued and approved.
Why Do Change Orders Happen?
Change orders are not a sign of failure. On complex projects they are almost inevitable. The causes tend to fall into a few recurring categories.
Design errors and omissions. Drawings and specifications are produced before a single shovel hits the ground, and they are rarely perfect. When a detail is missing, contradictory, or impossible to build as drawn, the work has to be corrected, and that correction flows through a change order.
Unforeseen site conditions. Excavation reveals rock, groundwater, contaminated soil, or buried structures that no one anticipated. Renovation work uncovers outdated wiring or structural problems hidden behind walls. These discoveries frequently require additional work that was never in the original scope.
Owner-requested changes. The client decides to upgrade finishes, reconfigure a layout, add a room, or change a system after construction has started. These discretionary changes are among the most common drivers of change orders.
Regulatory and code changes. A new code requirement, a permitting condition, or an inspector's interpretation can force modifications midway through a build.
Material availability and pricing. When a specified product is discontinued or delayed, substitutions are needed, and those substitutions often carry cost and schedule implications. Price volatility is a common trigger too, and some teams use price-locking tools to reduce the swings that would otherwise force a change order.
Because the causes are so varied, mature teams treat change orders as a normal part of project delivery rather than an exception to be feared. The goal is not zero change orders but a fast, transparent process for handling them.
The Main Types of Change Orders
Not every change order works the same way. Understanding the different types helps teams choose the right approach for the situation in front of them.
Additive and Deductive Change Orders
The simplest distinction is direction. An additive change order increases the scope and usually the price, for example adding a new section of landscaping. A deductive change order removes scope and reduces the contract value, such as deleting a planned feature to save money. Many change orders contain both, adding one item while removing another.
Lump Sum Change Orders
Here the contractor prices the change as a single fixed amount agreed before the work proceeds. This gives the owner cost certainty but requires enough detail to price accurately.
Time and Materials Change Orders
When the full scope is not yet clear, the work proceeds on a time and materials basis, with the contractor billing for actual labor and materials plus a markup. This is common for emergency repairs or investigative work where the extent of the problem is unknown until the work begins.
Unit Price Change Orders
For repetitive work measured in defined units, such as cubic yards of concrete or linear feet of pipe, the change is priced using pre-agreed unit rates from the contract. The final cost depends on the quantities actually installed.
Construction Change Directives
A construction change directive is a specific tool used when the owner needs work to start immediately but the parties have not yet agreed on price or time. It instructs the contractor to proceed while the commercial terms are negotiated in parallel, preventing delays during disputes over value.
The Construction Change Order Process
A reliable change order process follows a predictable sequence. Skipping steps is where projects get into trouble.
- Identify the change. Someone, often the contractor, architect, or owner, recognizes that the work needs to differ from the contract documents. The trigger is documented clearly.
- Submit a change request. The party initiating the change submits a formal request describing what needs to change and why. On many projects this starts as a request for information when the issue is a question about the design.
- Price and assess the impact. The contractor estimates the cost and the schedule impact. This is where accuracy matters most. Estimating tools help contractors and remodelers produce fast, defensible estimates, while construction financial software helps smaller businesses tie the pricing of a change directly to their overall project margins.
- Review and negotiate. The owner and their representatives review the proposed cost and time. There may be back and forth before agreement is reached.
- Approve and sign. Once both sides agree, the change order is signed and becomes part of the contract. Platforms like Procore and Autodesk Construction Cloud are widely used to route change orders for digital approval and keep a clear audit trail.
- Execute and track. The work continues and the change is tracked through to completion and payment. Field management tools help teams capture what actually happened on site, which is invaluable if the change is ever questioned later.
The discipline of moving through these steps in order, and documenting each one, is what separates smooth projects from contentious ones.
How Change Orders Affect Cost and Schedule
Every change order carries two kinds of impact, and teams often focus on one while ignoring the other.
The cost impact is the obvious one: the direct price of the added or removed work, plus any markup for overhead and profit. But there is also a less visible cost in disruption. Stopping and restarting work, resequencing trades, and remobilizing crews all carry expense that a simple materials estimate misses.
The schedule impact can be just as significant. A change that adds only a small amount of work may still push out the completion date if it sits on the critical path or forces other activities to wait. Time extensions need to be negotiated alongside cost, not as an afterthought.
There is also a cash flow dimension. Change order work is performed before it is formally approved and paid, which can strain a contractor's working capital, especially for smaller firms. Early payment and supply chain financing solutions exist precisely because the gap between doing the work and getting paid for it can be punishing. Strong change order management keeps that gap as short as possible by getting approvals signed quickly.
Best Practices for Change Order Management
Good change order management is less about avoiding changes and more about handling them cleanly and quickly. A few principles consistently separate well-run projects from troubled ones.
Document everything in writing and never let work proceed on a verbal instruction alone. Use a standardized form so that every change order captures the same information every time. Respond to change requests promptly, because delay is itself a cost. Price changes transparently, breaking out labor, materials, and markup so the owner can see what they are paying for. Track the cumulative impact of change orders against the original contract, since a series of small changes can quietly transform the budget. Finally, agree on the schedule impact at the same time as the cost, rather than leaving time extensions to be argued about at the end.
Centralizing all of this in a single system, rather than scattering it across emails and spreadsheets, is a significant improvement most teams can make. A clear audit trail is a strong protection against disputes.
Common Pitfalls to Avoid
Even teams that understand the process well fall into a handful of recurring traps. Knowing them in advance is one way to avoid them.
Proceeding on a promise. The most expensive mistake is starting work on a casual verbal go-ahead and documenting it later, or never. Without a signed change order, the contractor may never be paid for the work, and the owner may dispute that they ever approved it. Always wait for a signed document so payment is protected.
Confusing a change order with a change directive. A construction change directive forces a contractor to proceed with urgent changes before the price and time are fully agreed. This often leads to disputes, so it is critical to track time and costs meticulously while executing a directive.
Using non-standard forms. Industry-standard documents, such as the AIA G701 Change Order form from the American Institute of Architects, are widely recommended to prevent the ambiguities and disputes that come from improvised paperwork.
Pricing before the scope is clear. Quoting a fixed lump sum for a change that is still poorly defined often leads to a loss for someone. When the extent of the work is genuinely unknown, a time and materials or construction change directive approach protects both sides until the scope settles.
Ignoring the schedule impact. Teams routinely negotiate the cost of a change and forget the time, then argue at the end of the job about a completion date that quietly slipped weeks earlier. Every change order should state its effect on the schedule, even if that effect is zero.
Letting approvals pile up. Performing change after change while approvals sit unsigned is how contractors end up financing the owner's project out of their own pocket. The longer the backlog, the harder each one is to reconstruct and justify.
Underestimating the ripple effects. A change rarely affects only the trade doing it. Moving a wall touches electrical, plumbing, and finishes. Pricing only the direct work and missing the disruption to other trades is a common way that change orders end up underwater.
Conclusion
Change orders in construction are not a problem to be eliminated but a process to be managed well. They are the formal, enforceable way that a project adapts to the inevitable surprises of building in the real world, whether that means an unforeseen site condition, a design correction, or an owner who wants something better than the original plan.
The projects that handle change orders successfully are the ones with discipline: clear documentation, fast and transparent pricing, prompt approvals, and a single source of truth for tracking it all. When that discipline is in place, a change order stops being a source of conflict and becomes simply another step in delivering the building. Investing in a strong change order process, supported by the right estimating, financial, and field management tools, pays for itself many times over across the life of a project. Treat change orders not as an interruption to the work but as part of how the work gets done well.
FAQs
What is a change order in construction?
A change order in construction is a written amendment to the original contract that modifies the scope of work, the price, the schedule, or all three. Once signed by the authorized parties, it becomes a binding part of the agreement.
What is the difference between a change order and a change directive?
A change order is signed only after both parties agree on the cost and time impact. A construction change directive instructs the contractor to begin work immediately while those terms are still being negotiated, which prevents delays when an agreement cannot be reached quickly.
Who can approve a change order?
Only the parties authorized in the contract, typically the owner or their designated representative and the contractor. The specific approval authority and dollar thresholds are usually defined in the original agreement.
Are change orders bad for a project?
Not inherently. Change orders are a normal part of construction, especially on complex projects. Problems arise from poor handling, such as undocumented verbal changes or slow approvals, rather than from the existence of change orders themselves.
How can change orders be reduced?
The most effective levers are thorough design and constructability review before work begins, clear and complete contract documents, early identification of site conditions, and a defined process so that genuine changes are handled efficiently rather than expanding into disputes.
Do change orders always increase the project cost?
No. Additive change orders increase cost, but deductive change orders remove scope and reduce the contract value. Many change orders combine both, and the net effect depends on the specific change.