⚖️ Commercial & Legal Notice

Calculations for commercial planning and estimating purposes only; not legal advice. Aligned with US AIA A201-2017 § 7 and FIDIC Clause 13 variation standards.

Change Order / Variation Calculator

Calculate direct costs, overhead & profit (OH&P), bond markups, and cumulative contract sum adjustments under AIA A201 § 7 and FIDIC Clause 13.

Change Order Cost Inputs

Direct Cost (Labor/Mat/Eq, $)

General OH&P Markup (%)

Bond & Insurance Markup (%)

Original Contract Sum ($)

Change Order Valuation

CO = 5.81% of Contract

Total Change Order Value

$58,075

Adjusted Contract Sum: $1,058,075

Direct Cost Subtotal: $50,000

OH&P Markup Amount: $7,500

Subtotal before Bond/Ins: $57,500

Bond & Insurance Premium: $575

Cumulative CO Impact: 5.81%

Change Order Cost Breakdown Tier Stack

Frequently Asked Questions (FAQ)

What is a Change Order under AIA A201 § 7?

Under AIA A201-2017 Section 7.2, a Change Order is a written instrument signed by the owner, contractor, and architect stating their agreement upon a change in the work, amount of contract sum adjustment, and extent of contract time extension.

What is a Variation under FIDIC Clause 13?

Under FIDIC Red/Yellow Book Clause 13.1, a Variation is an instruction issued by the Engineer to alter, add, omit, or substitute work, valued according to Clause 12 or Clause 13.3 procedures.

How are Overhead and Profit (OH&P) markups calculated?

OH&P markup is applied to direct labor, material, and equipment costs. A typical 15% markup increases a $50,000 direct cost by $7,500 to $57,500.

Are bond and insurance premiums added to change orders?

Yes. Most public and commercial contracts allow 1% to 2% bond and risk insurance adjustment on the total subtotal of direct cost plus OH&P markup.

What is a Construction Change Directive (CCD)?

Per AIA A201 § 7.3, a Construction Change Directive orders a change in the work prior to final agreement on contract price or time adjustment.

What is the difference between additive and deductive change orders?

Additive change orders increase contract scope and sum; deductive change orders omit scope and credit the owner, typically excluding profit overhead recovery.

How does cumulative change order percentage impact contract risk?

Cumulative change orders exceeding 10% to 15% of original contract value signal scope creep, potential dispute risk, and increased surety bond exposure.

How do change orders feed into Interim Payment Certificates (IPC)?

Approved change orders modify the contract line item baseline on monthly payment applications (AIA G702/G703 or FIDIC IPC submissions).

Sources & Governing Codes

IBC 2021 Section 1011 Means of Egress & Occupant Load: IBC 2021 Section 1011 Means of Egress & Occupant Load View Standard

OSHA Standard 1926 Construction Safety Regulations: OSHA Standard 1926 Construction Safety Regulations View Standard

ADA 2010 Standards for Accessible Design: ADA 2010 Standards for Accessible Design View Standard