Change Order
Also known as: CO · change directive
A change order is a written amendment to an existing contract that adds, removes, or modifies work, and adjusts the contract price and schedule accordingly. It applies after a contract is in place — unlike an addendum, which changes the documents before bids are due.
Where change orders come from
- Owner-directed changes — a finish selection changes, an area gets added
- Design errors or omissions — the drawings and specification disagree, or a condition isn't detailed
- Unforeseen conditions — the slab fails a moisture test, the substrate is worse than represented
- Scope you correctly excluded — the work turns out to be needed and nobody else priced it
- Schedule impacts — acceleration, out-of-sequence work, additional mobilizations
Get it in writing before the work
Proceeding on a verbal instruction is the most common way subcontractors lose money on changes. If the schedule genuinely will not wait, a written construction change directive or even an email confirming the instruction and stating that costs will follow is far better than nothing.
Why exclusions decide change orders
Whether extra work is a change order or an argument usually turns on what your original proposal said. "Moisture mitigation excluded" is a strong position. Silence on moisture is not. This is why a maintained scopes library — the same exclusions and qualifications on every proposal — is worth more to a flooring contractor than almost any other document. See the flooring takeoff guide.
Related terms
- AddendumAn addendum is a formal change to the bid documents issued by the architect or general contractor before bids are due. It can revise drawings, specifications, quantities, the scope, or the bid date, and it becomes part of the contract documents.
- Scope of WorkA scope of work defines exactly what a subcontractor is and is not responsible for on a project. In a bid proposal it is usually expressed as inclusions, exclusions, and qualifications — and it determines whether extra work becomes a change order or an unpaid dispute.
- Schedule of ValuesA schedule of values is a breakdown of a subcontractor's total contract price into individual line items, each with its own dollar value. It is submitted after award and becomes the basis for monthly progress billing — you invoice the percentage complete of each line.