FAR Part 36: The Federal Acquisition Regulation Clauses That Shape Federal Construction Contracts
Federal construction contracts are governed by the Federal Acquisition Regulation (FAR) — specifically Part 36, which provides construction-specific rules, and additional clauses incorporated from other FAR parts. A federal construction contract isn't a standard commercial contract; it incorporates specific FAR clauses by reference, each of which has its own established body of case law in the federal boards of contract appeals and the Court of Federal Claims.
Contractors bidding federal construction need to know which clauses will be in the contract and what they mean in practice. The differences from commercial work are substantial — different procedures for changes, different grounds for termination, different damage recovery frameworks. A contractor who treats federal work the same as commercial work will miss claim opportunities, fail to protect rights, and run into procedural defenses to legitimate claims.
The Differing Site Conditions clause is one of the most important protections for federal construction contractors. It provides that if the contractor encounters unusual physical conditions that differ materially from what was indicated in the contract (Type I) or from conditions ordinarily encountered in work of the character provided for in the contract (Type II), the contractor is entitled to an equitable adjustment.
Two types of differing site conditions claims:
Differing site conditions types
- Type I — subsurface or latent physical conditions at the site that differ materially from those indicated in the contract documents
- Type II — unknown physical conditions of an unusual nature that differ materially from those ordinarily encountered in work of the character provided for in the contract
Type I claims are typically easier to prove because the contract explicitly indicated certain conditions and the actual conditions were different. A geotechnical report showing 10 feet of sandy soil when the contractor encountered 10 feet of rock is a Type I situation. Type II claims are harder because they require showing the conditions were outside what a reasonable contractor would expect for this type of work in this area.
To preserve a differing site conditions claim, the contractor must notify the contracting officer promptly — typically before the conditions are disturbed — and allow investigation. Proceeding without notice can waive the claim. The notice doesn't have to be perfect, but it must be timely and must identify the conditions.
The Changes clause gives the government broad authority to modify the contract unilaterally and gives the contractor the right to an equitable adjustment for the changes. Key elements:
FAR 52.243-4 Changes clause mechanics
- Government can issue written changes to the contract requirements within the general scope
- Changes can be formal (written change order) or constructive (government conduct that effectively changes the work)
- Contractor must submit a claim for equitable adjustment within 30 days after the change (subject to some flexibility for constructive changes)
- Failure to provide timely claim notice can limit or waive the claim
- Changes that exceed the general scope of the contract are outside the clause's authority
Constructive changes are a significant claim category. The government may not formally issue a change order but may, through directions, interpretations, or conduct, effectively require the contractor to perform different or additional work. Constructive change claims require the contractor to show the government's conduct effectively altered the work and that the contractor performed accordingly under protest.
The 30-day notice requirement is specific to the FAR changes clause and is often more rigorous than commercial notice requirements. Federal construction contractors track potential change events closely and submit claim notices well within the deadline.
The Default clause allows the government to terminate the contract if the contractor fails to perform. Grounds for default termination:
Grounds for termination for default
- Failure to complete the work within the contract time
- Failure to make progress so as to endanger timely completion
- Failure to comply with specified contract provisions
- Persistent failure to follow the direction of the contracting officer
Default termination has serious consequences: the government completes the work and back-charges the contractor for excess costs, the contractor loses any unpaid contract balance, and the surety (on bonded projects) is implicated. A default termination can also affect the contractor's ability to win future federal contracts — past performance ratings reflect terminations and affect responsibility determinations.
Default terminations are often contested. If the contractor can show that the failure wasn't its fault (government-caused delays, acts of God, severe weather, unusual circumstances), the default termination may be converted to a termination for convenience, with different financial consequences.
The Termination for Convenience clause allows the government to terminate the contract without specific breach by the contractor. Compensation follows a specific framework:
Federal T4C compensation framework
- Costs of completed and accepted work (at contract prices)
- Reasonable costs of work in process at termination
- Settlement expenses — costs of terminating subcontracts, legal costs, accounting costs
- A reasonable profit on completed work
- No profit on unperformed work
- Subject to dollar limits in the contract's schedule of payments and the termination itself
The federal T4C framework is more structured than typical commercial T4C provisions. The FAR specifies what's recoverable and what isn't, and decades of case law have refined the specifics. Federal construction contractors typically engage government contract specialists to prepare T4C settlement proposals because the preparation is specialized.
A termination for default that's later converted to a termination for convenience on appeal is a common dispute outcome. The difference in financial recovery is substantial — default means paying the government for excess completion costs; convenience means being paid for work performed plus settlement expenses. Contractors facing default termination should consider whether grounds for appeal exist before accepting the termination.
Most federal construction contracts include liquidated damages for delay — a specified daily amount the contractor pays if completion is late. The amount is set based on the government's estimated daily damages from delay (the government's cost of not having the facility available on time, including rent, operational disruption, and similar costs).
Federal LDs are generally enforceable if the amount is a reasonable pre-estimate of actual damages and isn't a penalty. Contractors challenging LDs must show the amount was manifestly excessive or bore no reasonable relationship to actual damages — a difficult burden. More commonly, contractors challenge the days of delay assessed, arguing that specific days were caused by excusable events (government delays, weather, etc.) that should be deducted.
Get AP insights in your inbox
A short monthly roundup of construction AP + accounting posts. No spam, ever.
No spam. Unsubscribe anytime.
Federal construction contracts typically specify key dates — notice to proceed, substantial completion, final completion. The contractor's obligations run from these dates. The Suspension of Work clause (FAR 52.242-14) gives the government the right to suspend work and provides for equitable adjustment if the suspension is unreasonable.
Suspension claims have specific requirements:
Suspension of work claim requirements
- Suspension was ordered by the contracting officer (or was constructive — conduct effectively suspending the work)
- Suspension lasted for an unreasonable period of time
- Suspension was not caused by the contractor's own acts
- Suspension caused the contractor to incur costs
Equitable adjustment for suspension can include extended overhead, idle equipment costs, and labor inefficiency costs during the suspension period. Federal case law has developed specific methodologies for calculating suspension costs (Eichleay for extended home office overhead, for example).
The Schedules for Construction Contracts clause requires the contractor to prepare and submit a construction progress schedule within a specified period after notice to proceed. The schedule is usually required to be updated periodically and is used by the government to monitor progress and assess delay claims.
The schedule is more than a project management tool — it's a contractual document with evidentiary weight. Federal delay claims typically depend heavily on schedule analysis. A contractor's entitlement to time extensions and delay damages often rises or falls with the quality of the schedule and the updates provided during performance.
The Inspection of Construction clause gives the government the right to inspect work during performance and on completion. The government can require correction of defective work, and final acceptance discharges the contractor's liability for defects except those covered by warranty provisions.
Final acceptance is a pivotal moment. It starts certain warranty periods, releases most of the retainage, and limits the contractor's ongoing obligations. But acceptance can be conditional — the government may accept with a punch list of items to be completed or corrected, and those items must still be addressed.
Federal construction disputes are governed by the Contract Disputes Act (CDA) and the Disputes clause. The framework:
Federal disputes framework
- Claim submitted to the contracting officer with supporting documentation
- Claim certification required for claims over $100,000 (certified statement that the claim is made in good faith and supporting data is accurate)
- Contracting officer issues a final decision (or fails to do so within specified time, deemed denial)
- Appeal to the Board of Contract Appeals (ASBCA, CBCA) or to the Court of Federal Claims
- Further appeal possible to the Federal Circuit
The certification requirement for claims over $100,000 is a specific federal contract concept. A deficient certification can make the claim non-existent for jurisdictional purposes. Contractors making federal claims above the threshold typically have counsel review the certification before submission.
Federal construction payment follows specific procedures. Progress payments are typically based on monthly payment estimates prepared by the contractor and approved by the contracting officer. The Prompt Payment Act applies — the government must pay within 14 days of receiving a proper invoice (for progress payments on construction) or pay interest. Subcontractors benefit from flow-down prompt payment requirements.
Retainage on federal construction is typically up to 10% and is released per the specific contract terms. Final payment requires completion of closeout documentation — releases, subcontractor payment certifications, warranty documentation, operations and maintenance manuals, and as-built drawings.
FAR Part 36 and the associated FAR construction clauses create a distinctive contracting framework for federal construction work. The Differing Site Conditions clause provides an important protection; the Changes clause establishes specific procedures for modifications; Termination for Default and Convenience have different consequences; Liquidated Damages are generally enforceable; the Suspension of Work clause provides remedies for unreasonable government-caused delays; and the Disputes clause under the Contract Disputes Act establishes the path for unresolved claims. Federal construction contractors who understand these clauses — and who preserve rights by providing timely notices, maintaining accurate schedules, and documenting claim circumstances — recover what they're entitled to. Contractors who apply commercial-contract practices to federal work consistently miss claim opportunities and concede defenses they could have preserved. Federal construction is a specialized contracting environment that rewards procedural rigor.
Written by
Jordan Patel
Compliance & Legal
Former corporate counsel specializing in construction contracts and tax compliance. Writes about the documentation layer — COIs, W-8/W-9, certified payroll, notice-to-owner deadlines — and the legal backbone behind audit-ready AP.
View all posts