What Causes Construction Change Orders—and How to Avoid Them

Construction change orders are often viewed as an unavoidable part of the building process. While some changes are necessary due to unforeseen conditions or evolving project requirements, many change orders can be traced back to issues that could have been identified and addressed before construction even began.

For owners and developers, change orders typically mean one thing: additional cost and additional time. Understanding what causes them is the first step toward minimizing their impact on your project.

What Is a Construction Change Order?

A change order is a formal modification to the original construction contract. It may involve changes to the scope of work, materials, schedule, design, or pricing after construction has already started.

When properly managed, change orders provide a structured way to handle necessary project adjustments. However, excessive change orders can quickly derail budgets and timelines.

The Most Common Causes of Construction Change Orders

1. Incomplete or Inaccurate Design Documents

One of the leading causes of change orders is incomplete plans and specifications.

When drawings lack detail or contain conflicting information, contractors are often forced to seek clarification during construction. In many cases, the resulting changes require additional labor, materials, or redesign efforts.

For example, a structural detail may conflict with an architectural drawing, or key dimensions may be missing entirely. Once construction is underway, resolving these issues usually comes at a premium.

How to avoid it:

• Conduct thorough design reviews before bidding.

• Involve contractors during the design phase.

• Allow adequate time for coordination between architects and engineers.

2. Unforeseen Site Conditions

No matter how carefully a project is planned, hidden site conditions can create challenges.

Examples include:

• Poor soil conditions

• Underground utilities that were not documented

• Environmental concerns

• Existing structural deficiencies during renovations

These discoveries often require changes to the construction approach, resulting in additional work and costs.

How to avoid it:

• Perform comprehensive site investigations.

• Invest in geotechnical studies when appropriate.

• Conduct detailed inspections before finalizing project budgets.

3. Owner-Initiated Changes

Sometimes the owner decides to make changes after construction has started.

This may include:

• Upgrading finishes

• Modifying layouts

• Adding new features

• Changing materials

While these changes may improve the final product, they often impact schedules, labor requirements, and procurement timelines.

How to avoid it:

• Finalize major decisions before construction begins.

• Establish a clear project vision early.

• Evaluate the cost and schedule impact of every requested change.

4. Material Availability Issues

Supply chain disruptions can force substitutions or redesigns when specified materials become unavailable.

A product selected during design may have extended lead times or may even be discontinued by the time construction begins.

How to avoid it:

• Verify availability during the design phase.

• Identify acceptable alternatives in advance.

• Procure long-lead items early whenever possible.

5. Scope Gaps and Assumptions

When project requirements are not clearly defined, different parties may make different assumptions about what is included.

For example, a contractor may price a project based on one interpretation of the plans while the owner expects additional work to be included.

These misunderstandings frequently lead to disputes and change orders.

How to avoid it:

• Clearly define project scope.

• Document responsibilities and expectations.

• Review bid packages carefully before issuing contracts.

6. Regulatory and Code Requirements

Building codes, permitting requirements, and regulatory reviews can occasionally trigger project changes.

In some cases, authorities having jurisdiction may require modifications that were not anticipated during design.

How to avoid it:

• Engage code consultants early.

• Coordinate with permitting agencies during design.

• Stay informed about local code requirements.

The Best Strategy: Focus on Preconstruction

The most effective way to reduce change orders is to invest in thorough preconstruction planning.

Projects that involve contractors early in the design process often experience fewer surprises because construction expertise is applied before critical decisions are finalized.

During preconstruction, contractors can help:

• Identify constructability concerns

• Verify budgets

• Review material availability

• Coordinate trades

• Reduce design conflicts

Many of the most expensive change orders are not caused by construction mistakes—they are caused by planning gaps that existed long before ground was broken.

Final Thoughts

Change orders are sometimes unavoidable, but they should not be accepted as a normal cost of doing business.

The majority of costly project changes stem from incomplete planning, unclear scope, design coordination issues, or decisions made too late in the process.

Owners and developers who prioritize thorough preconstruction planning, early contractor involvement, and detailed project coordination are far more likely to deliver projects on time and within budget.

The cheapest change order is the one that never has to be written.