A change order is a written amendment to your construction contract that states what work is being added or removed, what it costs, and how it affects the schedule — signed by both parties before the work happens.
A change order is a written amendment to your construction contract that states what work is being added or removed, what it costs, and how it affects the schedule — signed by both parties before the work happens. Verbal changes are how remodels end in disputes. The document is the whole protection.
Change orders have a bad reputation, and part of that is earned. But most of the anger around them isn't about the change itself. It's about finding out afterward, at a number nobody discussed, on an invoice that arrives at the end.
Quick answer
Every change order needs seven elements. Missing any one of them creates a dispute later.
Sign before the work happens, not after. That's the rule that does the actual work.
Three causes of change orders are legitimate. One is not.
Track a running contract total, not a list of separate slips of paper.
The seven elements of a real change order
A change order that's missing any of these is an invitation to argue. Use it as your acceptance checklist.
# | Element | What it must say |
|---|---|---|
1 | Reference and number | Sequential number tied to the original contract, e.g. "CO-004 to Contract dated 3/14" |
2 | Description of the change | Physical description of added and deleted work, in the same detail level as the original scope |
3 | Reason | Why this is happening — owner request, concealed condition, code requirement, or design conflict |
4 | Cost | The dollar amount, ideally broken into labor, material, and markup. Credits shown as negatives. |
5 | Schedule impact | Days added or "no change to completion date." Never left blank. |
6 | New contract total | Original sum, prior changes, this change, revised total. Running math on every one. |
7 | Signatures and date | Both parties, dated before the work begins |
Element 6 is the one homeowners most often let slide, and it's the one that keeps you oriented. When each change order restates the running total, you always know what the project costs today. Without it, you're reconstructing the number from a folder of paper in month four.
Three legitimate causes, and one that isn't
1. You changed your mind. Completely normal. You saw the space framed and want the shower niche moved. That's a change order, priced and signed. No drama.
2. A concealed condition was discovered. Rot behind the tub, a drain that isn't where it should be, undersized framing. This is exactly what your contingency exists for.
3. A code or inspection requirement surfaced. The inspector requires an upgrade that wasn't in the original scope. Common in older homes, where opening a wall can trigger requirements for what's now exposed.
And the one that isn't: work that was always necessary but was left out of the bid. If a bathroom remodel bid contained no line for a new shower valve, the valve was never optional — it was omitted. That's an estimating miss, not a change in the work. It's worth a direct, calm conversation about who absorbs it. This is also precisely why normalizing bids before you sign matters so much: most illegitimate change orders were visible as blanks in the bid weeks earlier.
The rule that prevents most disputes
Nothing gets built before the change order is signed.
It sounds rigid on a jobsite where a crew is standing around waiting. It's still the rule. The moment you allow "we'll write it up later," you've given up your ability to say no to the price — because the work is already in your house and you're being asked to pay for it retroactively.
For genuinely urgent items — an active leak, an unsafe condition — agree on an emergency protocol in advance: the contractor may stabilize the condition immediately up to an agreed dollar cap, with documentation and a change order to follow within a set number of days. That's a reasonable exception written into the contract, not an ad-hoc concession made under pressure.
How change order pricing usually works
There are three common structures, and your contract should say which applies:
Lump sum. A fixed price for the change. Clearest for the homeowner. Best when the work is well defined.
Unit price. A rate per unit — per square foot, per fixture, per linear foot — established in the original contract. Good for changes in quantity.
Time and materials with a cap. Actual cost plus an agreed markup, with a not-to-exceed number. Appropriate when the extent genuinely can't be known until work is underway. Always insist on the cap and on receipts.
Markup on change orders is normal and legitimate — the contractor is carrying overhead, coordination, and risk on the added work. What should be consistent is the rate. If the contract states overhead and profit at a given percentage, change orders should use that same percentage.
Common mistakes
Approving by text message. A text saying "sounds good" is not a priced, scheduled, signed document. If your contractor uses a project app that captures the same seven elements with an electronic signature, that works. A thumbs-up emoji does not.
Leaving schedule impact blank. Small changes accumulate into weeks. If each one says "no change," get it in writing so the completion date holds.
Not tracking the running total. Nine changes at $900 is $8,100, and it never felt like a big decision.
Batching changes at the end. Insist on issuance within a few days of the triggering event, while the facts are fresh and you still have leverage.
Your action plan
Before signing your contract, confirm it defines the change order process, the markup rate, and the emergency protocol.
Set up a single tracking sheet: number, date, description, cost, days added, running total.
Require the seven elements on every change order you're asked to sign.
Sign before work starts. Every time.
Reconcile your contingency balance against the running total weekly.
File every signed change order with the contract and keep them after closeout.
Frequently asked questions
Do I have to sign a change order?
You have to sign it before that work proceeds, but you don't have to sign one you disagree with. You can decline the change, ask for a revised price, request a different approach, or ask for the cost breakdown. Signing is your approval, not an obligation.
Can a contractor charge for extra work without a signed change order?
That depends on your contract and on your state's law, and some states have specific requirements for home improvement contracts. Practically, this is why the sign-first rule exists — it removes the question entirely instead of leaving it to be resolved after the fact.
How much markup is reasonable on a change order?
Whatever your contract states, applied consistently. The number varies by market, company structure, and project type. The thing to watch isn't the percentage in isolation — it's whether change order markup matches the rate used in the original contract.
What's the difference between a change order and an allowance overage?
An allowance overage happens when you select a product costing more than the amount the contract allowed for it. The work didn't change; the material cost did. Many contractors document overages through change orders anyway, which is good practice because it keeps the running total accurate.
How many change orders are normal on a remodel?
There's no universal number, and it depends heavily on how complete the original scope was and how old the house is. A tight scope on a newer home may see very few. An older home with layout changes will see more. A high count isn't automatically a red flag — a high count with vague descriptions is.
Should change orders come out of my contingency?
Change orders for concealed conditions and code-triggered requirements should. Change orders for upgrades you chose should come from your selections money. Keeping those separate is what lets you know whether you're actually over budget or just spending on things you decided you wanted.
Keep going
Change orders are cheapest to prevent. Start with a complete scope of work, fund them properly with the right contingency, and catch the omissions early by comparing bids line by line.
Plan your project with better information.
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This content is provided by Smart Tools Construction Academy for general educational purposes. It is not project-specific construction, engineering, architectural, legal, tax, environmental, or safety advice. Codes, permits, licensing rules, costs, conditions, and accepted practices vary by project and jurisdiction. Consult the applicable building department and qualified licensed professionals before making project decisions or performing hazardous or regulated work.
