What is change management on a construction project?
Change management is the procedure used to handle modifications to the scope, cost, or schedule of a project relative to what was agreed in the original contract. Instead of accepting changes verbally and arguing later about who pays for what, every modification is raised as a change order: it is described, priced, authorized, and only then executed.
The whole point of change management is to protect both parties. It protects the contractor from performing extra work the owner later refuses to acknowledge; it protects the owner from charges they never authorized and from a schedule that stretches with no explanation. A project with no change management almost always ends in conflict: work done and never billed, cost overruns with no backup, and a completion date that moved without anyone knowing why.
What is a change order and what types are there?
A change order is the document that formalizes a modification to the contract: it describes what changes relative to the original scope, how much that change costs, and what effect it has on the schedule. It is the basic unit of change management. Depending on what they do to the scope, change orders fall into two types.
- Additive change order: adds work or scope that was not in the contract (an extra wall, a deeper foundation, an additional finish). It adds to the cost and often to the schedule as well.
- Deductive change order: removes planned work or scope (a line item is cancelled, a quantity is reduced, the owner takes over a supply). It reduces the cost and can shorten the schedule.
- Change with no effect on the amount: sometimes one material or method is swapped for another of equivalent cost; even so, it is worth documenting to leave a record of the agreement.
How does each change impact cost and time?
A common mistake is to price only the money side of a change order and forget the time. Every change has two impacts you have to estimate together, because extra work not only costs more: it can also push the delivery date, and that has consequences for penalties, for resources, and for the rest of the line items.
The cost impact is priced like any other item: quantity times the unit price of the work added or removed, with its overhead and profit. The time impact is estimated by looking at how the change affects the project sequence, especially if it touches critical-path activities; extra work off the critical path may not move the schedule, but work on the critical path pushes it day by day.
- Cost impact: the amount the change order adds (additive) or subtracts (deductive) from the contract.
- Time impact: the days the change adds to or removes from the schedule.
- A change can raise the cost without moving the schedule, or move the schedule with little cost: that is why the two are priced separately.
- The changes that touch the critical path are the ones that truly push the delivery date.
How is a change formalized: the signed amendment?
Pricing the change is not enough: it has to be authorized in writing before it is executed. It is formalized through an amendment (also called a modification agreement or contract change) that both parties sign. That signature is what turns a verbal request into an enforceable commitment: it defines the new scope, the new amount, and, if applicable, the new schedule.
The order matters: first you document and sign the change order, then you execute it. Executing before you have the signature is the mistake that leaves the contractor with no basis to bill. On public projects, these modification agreements come with specific rules and limits; on private projects, the contract sets the criteria, but the logic is the same: no signature, no recognized change.
- Document the change order with its scope, cost, and time before executing.
- Have both parties sign it in an amendment or modification agreement to the contract.
- Execute the change only after the signature, never before.
- Keep the amendment with the contract: it is the backup for updating the budget and billing it in the payment application.
How do change orders affect the budget and the payment applications?
An authorized change order does not live on its own: it reconfigures the budget and gets billed in the payment applications. In the budget, each change order adjusts the contract amount: additive orders raise it, deductive orders lower it, and the original contract plus the change orders gives the current value of the project. Tracking this running total is what tells you, at any moment, what the contract is really worth.
In the payment applications, the work of a change order is billed like any other progress, but at the price agreed in the amendment: you measure the completed portion of the modified scope, value it, and include it in the period application. That is how change management closes the loop: the change is documented, it adjusts the budget, and it gets billed in the application, so no extra work falls outside billing and no reduction goes without a deduction.
- Budget: current amount = original contract + additive − deductive.
- Payment applications: the change order scope is billed at its agreed price, like any other progress in the period.
- The running total of change orders tells you how far the project has drifted from the base contract.
- Without recording the change in the budget and the application, the extra work gets built but never billed.
How to manage change orders with Matterial
Managing changes on loose spreadsheets — one order here, one amendment there, the budget out of date — is exactly what makes extra work slip through unbilled and leaves nobody sure of the current contract amount. The key is to record every change order with its cost and its time in the same place where the budget lives, so the current amount and the schedule recalculate on their own with each authorized change.
With change orders tied to the budget and to the payment applications, every piece of extra work is documented, updates the contract, and gets billed in its period — which is exactly what avoids the "we already agreed on this" arguments at the end of the job.