Construction Change Orders: Why the Work Is Not the Problem, the Paperwork Is

How contractors handle scope changes without losing money, why a change order is an authorization chain rather than a form, and what Florida law says about getting paid for work nobody signed off on. Reference content for contractors, project managers, and the teams who bill and track their jobs.

The most expensive words on a jobsite are “while you’re here, can you also.” A homeowner says it standing in the kitchen. A general contractor says it to a sub between phone calls. The crew, wanting to be helpful and not wanting to stop, does the work. Weeks later the invoice for that extra work goes out, and the answer comes back: nobody approved that. Now the contractor has paid for labor and materials, has no signed authorization, and is arguing over money instead of building.

That is the change order problem, and notice what it is not. It is almost never a dispute about whether the work happened or whether it was good. It is a dispute about authorization: who agreed to the change, at what price, before it was done. The work is rarely the problem. The paperwork is the problem, or more precisely, the missing paperwork. A change order is the mechanism that turns “extra work” into “billable work,” and contractors who treat it as an afterthought give away profit one favor at a time.

Quick Answer: What to Do the Moment Scope Changes

When work comes up that is not in the original contract, the sequence matters more than the speed:

Stop before starting. Do not begin out-of-scope work on a verbal request. The moment to get paid is before the work, not after.
Identify who can actually authorize it. Only the person named in the contract as authorized to approve changes can bind the other party. A site superintendent saying “go ahead” may not count.
Price it in writing. Scope of the added or deleted work, the cost, and the schedule impact, itemized.
Get the signature before the work. Once signed by the authorized parties, a change order generally becomes a binding amendment to the contract, carrying the same legal weight as the original.
Then open a budget line for it. Track the change order as its own line in your job costing, separate from the original contract, so you can see how scope growth is moving the job.

The single rule that prevents most change order losses is the fourth one: signature before work. Everything else is detail around that rule. A contractor who follows it has a billable amendment; a contractor who skips it has a favor he will fight to get paid for.

What a Change Order Actually Is

A change order is a written agreement that modifies a signed construction contract, changing the scope, the price, the schedule, or some combination of the three. Once signed by the authorized parties, it generally becomes a legally binding amendment, the same contract, now adjusted. On projects using the standard American Institute of Architects documents, the change order form is the AIA G701, and on larger projects it typically requires three signatures: owner, contractor, and architect.

But describing a change order as a form misses what makes it work, and what makes it fail. A change order is not really a piece of paper. It is an authorization chain. Three things have to line up: a change to the work, agreement on what that change costs and how it affects the schedule, and a signature from someone with the authority to bind the party paying for it. The form is just where those three things get recorded. When a change order dispute happens, it is almost always because one link in that chain was skipped, usually the signature, usually because the work felt small or urgent and stopping to paper it felt like bureaucracy.

This is why the most disciplined contractors treat the change order process as a reflex rather than a chore. The reflex is simple: new work that is not in the contract does not start until it is authorized in writing by someone who can authorize it. Everything expensive about change orders traces back to a moment when that reflex did not fire.

The Three Words That Cost the Most: “Authorized,” “In Writing,” “Before”

Each of the three links in the authorization chain fails in a predictable way, and each failure has a name on the invoice nobody pays.

Authorized. Not everyone on a project can approve a change. The contract names who can, and a change agreed to by someone without that authority may not bind the owner. A homeowner’s spouse, a tenant, a site superintendent, a project engineer: any of them might say “yes, do it,” and none of them might have the contractual power to commit the money. Before treating a change as approved, a contractor needs to know the request came from the person the contract actually empowers to make it. On public projects this is stricter still, which the Florida section below covers.

In writing. A verbal “go ahead” feels like agreement in the moment and evaporates in a dispute. The point of writing is not formality; it is that memory and good intentions do not survive a payment fight. A written change order records what was agreed while everyone still agrees, so that when the relationship cools, the document speaks instead of two people’s recollections. Many contracts contain a clause stating that all modifications must be in writing and that oral or field directives are not binding, and that clause exists precisely because field directives happen constantly.

Before. This is the link that breaks most often and costs the most. Work done before authorization is a bet that the owner will agree to pay afterward, and that bet is made at the worst possible moment to negotiate, after the leverage is gone. Before the work, the contractor can decline to proceed without an agreement; after the work, the contractor is asking to be paid for something already received. The same change order is a negotiation before the work and a plea after it.

What Florida Law Says About Unsigned Changes

Florida treats this differently depending on whether the project is public or private, and the difference matters enough that a contractor should know which set of rules applies before the first change comes up.

On public projects, Florida is strict. Under the doctrine of sovereign immunity, recognized by the Florida Supreme Court in County of Brevard v. Miorelli Engineering, a government entity generally cannot be bound by an oral or implied change to its contract. The change has to be an express, written change order. A contractor who does extra work for a public owner on a verbal instruction, without a written change order, is in a weak position to get paid. The law does not allow the government to be bound the way a private party might be. Public construction contracts are written around this, with explicit provisions for how the owner or its agent requests changes in writing.

Florida also added a contractor protection here. Effective for contracts entered into on or after July 1, 2025, Florida Statute section 218.755 requires a local government to respond promptly to change orders. When a contractor submits a price quote for a change order that the local government requested or issued, and the quote meets the statutory and contractual requirements, the government must approve or deny it in writing within 35 days of receiving it. A denial has to specify what is deficient and what would fix it. And there is a real consequence for silence. If the local government fails to respond within the deadline, the statute provides that the change order and price quote are deemed approved, and the government must pay the quoted amount once the change is complete. The statute was created because contractors were submitting change order proposals, incurring the cost of preparing them, and then waiting indefinitely for a response. The 35-day rule puts a clock on the public owner, with approval as the default if the clock runs out.

On private projects, the picture is less absolute. Many private contracts contain a “no oral modification” clause, but Florida courts will sometimes enforce an oral modification anyway, particularly where the owner watched the changed work happen, accepted it, and said nothing, so that refusing to pay would be inequitable. This is not a strategy to rely on; it is a fallback that turns into litigation. The reliable path on private work is the same as on public work: get it in writing and signed before proceeding. The difference is only in what happens when you do not, and on a public project the answer is often that you simply do not get paid.

	Public project	Private project
Oral or implied change	Generally cannot bind the owner (sovereign immunity)	Sometimes enforceable, but only through a dispute
What is required	Express, written change order	Written change order is the reliable path
Contractor protection	35-day response rule (Fla. Stat. 218.755)	Depends on the contract
Risk of skipping it	Often simply unpaid	Litigation over what was agreed

Because this is where construction overlaps with contract law, the specific rules that apply to any one project depend on the contract and the facts. A contractor facing a real dispute over an unsigned change should talk to a construction attorney rather than rely on a general description.

Pricing the Change Without Giving Away the Markup

A change order is also where contractors quietly lose margin even when the paperwork is right. The added work gets priced for its direct cost, the labor and materials, and the overhead and profit that should ride on top get left off because the change feels small or the contractor is hurrying to keep the job moving.

A change order should be priced the way the original bid was: direct labor at the burdened rate, materials, equipment, and the overhead and profit markup that the business needs to stay solvent. To make that concrete with illustrative numbers: say a change adds $2,000 of burdened labor, $1,000 of materials, and $500 of equipment time, for $3,500 in direct cost. A contractor who bills that $3,500 has covered his costs and earned nothing for the disruption, the rescheduling, and the office time the change consumed. The same change with a 15% overhead and profit markup bills at about $4,025, and that $525 is not padding; it is the margin the original bid carried on every other dollar of work, applied to the new work too. The standard AIA process is explicit that a contractor should not be made to absorb the general conditions and overhead that belong in the markup, and should also not double-charge for work already covered by the original contract. Both errors happen. The first gives away money; the second invites a fight. A change priced cleanly, with the same cost structure as the original bid, is both fair and defensible.

There is a related trap on the timeline. A change that adds work often adds days, and a change order that adjusts the price but stays silent on the schedule sets the contractor up to absorb the blame for a delay the change itself caused. The schedule impact belongs in the change order alongside the price, even when it is zero, stated explicitly so there is no argument later.

How a Change Order Moves Through Job Costing

A signed change order is not the end of the process. It is the beginning of a tracking problem, and contractors who paper the change perfectly and then fold it into the job invisibly lose the ability to see what scope growth did to the project.

The discipline is to track each change order as its own budget line, separate from the original contract value, rather than blending it into the existing numbers. There are two reasons. First, the original contract amount stays clean, so the contractor can always see the baseline he bid against and compare it to where the job actually landed. Second, the change orders become visible as a group, which is how a contractor learns that a particular kind of job, or a particular client, generates constant scope creep that the original bids never account for. A job that finishes on budget after three change orders did not finish on budget; it finished over the original scope, and only separate tracking shows that.

This is the point where change orders connect to the rest of a contractor’s financial picture. The job cost report has to absorb the change: new cost codes or budget lines for the added work, so that actual costs on the change can be tracked against the change order’s own budget rather than muddying the original. The work-in-progress schedule has to absorb it too, because an approved change order adjusts the total contract value, and a WIP report still measuring progress against the original contract amount will misstate how complete the job is. Real-time job cost data also works the other way. When costs on a cost code start running past the budget because conditions in the field changed, that variance is often the early signal that a change order is warranted. The contractor catches it while there is still leverage to negotiate, rather than after the cost is already absorbed.

The Field Is Where Change Orders Are Won or Lost

Every rule above is an office rule, and change orders do not break in the office. They break in the field, in the gap between the moment a change is needed and the moment it is authorized.

The crew is on site, the owner points at something, the work is obviously needed, and stopping to generate a written change order feels like getting in the way of progress. So the crew proceeds, intending to paper it later, and later the details are fuzzy and the owner remembers the conversation differently. The fix is not a better form. It is a field habit: the people on the jobsite have to understand that out-of-scope work does not start until it is authorized, and that this rule protects their company’s ability to get paid, not just the office’s filing system. Digital change order tools help here, because an owner can approve a priced change from a phone in under a minute, which removes the main excuse for proceeding without authorization. But the tool only matters if the field reflex exists first.

This applies with particular force to subcontractors. A general contractor who lets a sub perform out-of-scope work without a written change order can end up paying the sub for work the GC cannot bill back to the owner, because the authorization chain broke at the GC’s own level. The rule the GC enforces upward, get it in writing before proceeding, has to be enforced downward too.

What Disciplined Change Order Management Looks Like

The contractors who do not lose money on change orders are not the ones who avoid changes; changes are normal, and almost every job has them. They are the ones for whom the authorization chain is automatic. New work that is not in the contract stops until someone with authority approves it in writing, at a price that includes overhead and profit and states the schedule impact, all of it settled before a tool comes out. The signed change order then opens its own budget line, flows into the job cost report and the WIP schedule, and stays visible as a separate number through closeout.

None of that is complicated. What makes it hard is that every link in the chain is easiest to skip at exactly the moment skipping it feels reasonable: the work is small, the client is friendly, the crew is already there, the paperwork can wait. The whole discipline comes down to refusing that reasonable-feeling shortcut, every time, because the shortcut is where the money leaks. The change order is not the bureaucracy that slows the work down. It is the difference between work you did and work you get paid for.

This article is general information, not legal, tax, or accounting advice. Construction contract law, lien rights, and public-procurement rules are complex, fact-specific, and change over time. Statutes and rules cited here, including Florida Statute section 218.755, reflect the law as understood at the time of writing and may since have changed. Whether an oral or unsigned change is enforceable, and what a contractor’s rights are in any particular dispute, depend on the specific contract and circumstances. Nothing here creates a professional relationship or should be acted on without consulting a licensed Florida construction attorney or a qualified accounting professional about your specific situation.