Raise it the hour you find it, put it in writing before anyone touches the work, and hand it over standing in the room rather than by text at 9pm. The customer you lose is almost never the one who got a change order. It is the one who got a surprise line on the final invoice. The average remodeler nets 6.3% (NAHB Remodelers' Cost of Doing Business Study, 2024 data, published April 2026), so on a $42,000 kitchen the entire profit on the job is about $2,650 — one afternoon of unbilled subfloor repair and the lumber to do it. California requires the change order signed before the changed work begins. Massachusetts requires every modification in writing, agreed to by both parties.
When should you raise a change order?
The hour you find the condition. Not that evening, not on Friday, and never after the work is done.
There is a window that opens the moment you pull the vanity off the wall and closes the moment you start cutting. Inside that window you are a professional reporting a discovery. Outside it you are a contractor asking to be paid for work nobody agreed to. Same rot, same price, completely different conversation. That is the whole difference.
Two habits that decide which side of the window you are on:
Photograph the condition before you cover it. Soft subfloor, undersized wire, a joist somebody notched for a drain in 1974. Take the picture with your phone before the new material goes over it. A photograph ends the argument about whether the problem was real. A description of a photograph does not.
Stop work on that item only. Keep the crew moving on everything else. A contractor who downs tools on the whole job to force a signature has turned a $600 repair into a hostage negotiation, and the homeowner will remember it long after they have forgotten the money.
What has to be on a change order?
Enough that a stranger reading it in six months can tell exactly what changed, what it cost, and what it did to the finish date. California names most of it: the scope of the extra work, the cost added to or subtracted from the contract, and the effect on the schedule of progress payments.
| Line | What it stops |
|---|---|
| Change order number and date | An argument about which version was signed |
| Reference to the original contract or estimate | A document floating free of the job it belongs to |
| Description of the changed condition | "You never told me the floor was bad" |
| Description of the changed scope | Paying for a repair and expecting a remodel |
| Amount added to or subtracted from the contract price | A final invoice nobody can reconcile |
| New contract total | The homeowner doing arithmetic they will get wrong |
| Effect on the payment schedule | Fronting the material out of your own account |
| Effect on completion, in working days | The date they quote back to you in week six |
| Signature and date, both parties | Everything above being worth nothing |
One condition per change order. Do not bundle the rotten subfloor, the panel that will not take another circuit, and the tile the homeowner upgraded into a single document with one total on the bottom. Bundled, the customer has to reject all of it to reject any of it, so they argue about all of it. Separated, they sign two and think about the third.
What should you charge for a change order?
Your normal gross margin is the floor. Remodelers averaged 29.9% gross in 2024 (NAHB), and a change is more expensive to deliver than the same work priced at the start, because it arrives out of sequence, usually with a second trip to the supply house.
Work it through on a soft subfloor under a vanity:
| Line | Cost |
|---|---|
| Labor, 4 hours at a burdened rate of $58 | $232 |
| Plywood, sister stock, fasteners, adhesive | $140 |
| Supply house run, 1 hour | $58 |
| Direct cost | $430 |
| Price at a 29.9% gross margin ($430 ÷ 0.701) | $613 |
Call it $625. Then set a minimum — $250 is reasonable for most remodeling work — because writing the document, pricing it, and getting it signed takes the same twenty minutes whether the change is worth $90 or $9,000. Without a minimum you will quietly absorb every small one, and the small ones are most of them.
A position worth defending: never discount a change order to keep the peace. You are not buying goodwill, you are teaching the customer that your first number is negotiable, and there are usually four more changes coming on the same job.
How do you say it without losing the customer?
Lead with the decision, not the money. Give two real options and name what happens if they do nothing. Then leave the room.
Something close to this, said standing on the floor in question:
"I pulled the vanity and the subfloor under it is soft, about three feet out from the wall — here, look. I can't set new tile on that. Two ways to go. I cut out the bad section and sister the joist, $625, adds a day to the finish. Or I tile over it, and you'll be pulling this floor up again inside a couple of years, and I can't warranty it. I'd do the repair. Here's the change order. Take a minute with it, I'll be outside."
Four things are doing the work there. The homeowner sees the problem with their own eyes. There is a real alternative, so the answer is not a yes-or-no about money. The consequence of declining is stated plainly and without threat. And you leave, because nobody signs anything with a contractor standing over them.
The word to cut is "extra." Extra sounds like an upsell. "This wasn't in what we priced" is the same sentence and it is a fact about the scope rather than a request for money.
Is a written change order legally required?
In two of the largest remodeling states, yes, and getting it wrong is a licence problem rather than a paperwork problem.
California. The CSLB is direct about it: if the contract price or scope of work needs to change, it must be done with a written change order signed by the customer and the contractor prior to the change, which then becomes part of the contract. Business and Professions Code 7159 puts the change-order procedure itself in the list of required contract terms, on any home improvement work over $500.
Massachusetts. Contracts over $1,000 must be in writing, and any modification to the original contract must be in writing and agreed to by both parties. Section 17 of Chapter 142A makes it a prohibited act to deviate from the plans or specifications in any material respect without the owner's consent, and a violation of that chapter is an unfair or deceptive act under Chapter 93A. On a willful violation, 93A carries two to three times actual damages plus the homeowner's attorney's fees. A $900 change you did on a nod can end up costing multiples of $900 to argue about.
Write them everywhere, including the states with no statute on it. You do not get to choose which document a judge reads.
What this misses
Two states, not fifty. California and Massachusetts are named because their rules are explicit and published. Most states regulate residential contracts above some threshold and the numbers differ everywhere, so check your own board before copying a figure off this page.
Some changes should be eaten, and pretending otherwise makes you tiresome. A $40 fitting, twenty minutes of caulk, a switch plate somebody stepped on. Write a threshold down — under $100 in cost and under half an hour, it goes in the job — and then hold to it in both directions. Both directions matters.
A change order cannot rescue a bad original number. If the estimate was short before anyone found rot, the change orders are just a slower way of discovering it, which is a different problem and starts with what belongs on the estimate in the first place. Whether the document you handed over binds you at all depends on how it was worded, which is the estimate versus quote versus bid question, and the same state boards that police change orders also cap what you can take as a deposit.
The reason change orders get skipped is never that a contractor thinks they are a bad idea. It is 4pm, the joist is open, and writing one properly means a laptop that is at home. BidWalk builds the line items while you are still standing over the hole, so the document exists before the decision does.
