A Change Comes Up Mid-Job on a Commercial Contract: Decision Tree

Why this matters

On a residential job a change is a handshake you write up later. On a commercial contract it is a timed, formal process, and the contract will hold you to every step you skip. The dangerous part is that the work can be completely real and necessary and still go unpaid because you gave written notice a day late or built the extra without authorization. This tree is the order you follow the moment something on site stops matching the contract documents.

Start here: the clock is already running

The instant reality diverges from the drawings, specs, or scope, a notice clock may have started. Commercial change and claim clauses commonly require WRITTEN notice within a short window, often a handful of days from when you discover the change, and the exact count and what starts it live in your contract, so read that clause before the job, not during it. Your first move is not to grab a tool or refuse the work. It is to open the changes clause and start a dated written record today.

Two terms you need before you branch:

• Change order (CO): a signed amendment adding or removing scope with an agreed price and time. Safe to proceed.
• Change directive: a written order telling you to proceed with a change before the price and time are settled. You generally must do the work and resolve the number after.

What kind of change is it?

Branch by what triggered it.

The owner or GC asked for something not in the contract. This is a directed change. Get it in writing before you build. If they issue a formal change directive, you likely must proceed even without an agreed price, but you proceed under protest, meaning you do the work while stating in writing that you reserve your right to fair payment, and you track every hour and dollar on daily tickets. Never do directed extra work on a verbal "just do it."

The site does not match the drawings (a differing site condition). You hit something the documents did not show: rock, an unmarked line, rotten substrate, a hidden obstruction. Stop work in that area, photograph it before you disturb it, and give written notice immediately. A differing site condition is only compensable if you flag it before you cover it up or work through it. Bury it first and you have destroyed your own evidence.

The drawings and specs conflict with each other. Do not pick one and build. Submit an RFI (request for information, a written question to the design team asking them to resolve the conflict) and wait for the answer in writing. Building to your own guess makes the rework your cost.

You spot work that should be done but nobody asked for. Do not just do it and bill it. Flag it in writing, propose it as a change, and get authorization first. Unauthorized betterment is the classic way to do real work for free.

Do you keep working while the number is unresolved?

Often yes, and that is the trap coming off residential work.

• If you hold a written change directive, keep the job moving; refusing can put you in breach. Proceed documented: daily force-account tickets (a signed daily record of the labor hours, workers, equipment, and materials spent on the changed work) signed by the GC's rep on site each day.
• If it is a differing site condition or a conflict you flagged, follow the contract's stop-or-proceed instruction. Usually you stop only the affected work, keep the rest moving, and wait for written direction.
• Never let "we will sort the paperwork later" become the habit. Later is when memories fade and the person who authorized it has moved to another project.

Build the paper trail that gets you paid

Whatever the branch, the record is the same:

• Written notice inside the contract's deadline. A dated email that references the changes clause counts; a hallway conversation does not.
• Daily tickets for any time-and-materials or force-account work, signed on site by the GC's rep that day. An unsigned ticket at month-end is an opening offer, not a record.
• Photos before, during, and after, especially for anything about to be covered.
• Log the pending change even before it is approved. A change that never makes it into a pay application is money you walked away from.

Recap

1. Open the changes clause and start the notice clock the moment something differs.
2. Directed change: written authorization before you build; a formal directive means proceed under protest with daily tickets.
3. Differing site condition: document before you disturb, then notice immediately.
4. Drawing conflict: RFI, and wait for the written answer.
5. Work you noticed but nobody ordered: propose it, get authorization, then do it.
6. Keep working only where the contract requires, and paper every hour.

References

• Standard construction change and differing-site-conditions provisions (AIA A201, ConsensusDocs changes and claims clauses)
• Trade-standard force-account and daily-ticket practice
• See related: The Change-Order Discipline Commercial Work Demands; Documenting Commercial Work to Survive a Payment Dispute