A construction acceleration claim is the most expensive kind of delay claim, and the version that catches owners is the one where nobody ever used the word. It is built out of an extension request that was refused and a completion date that was insisted on anyway.
Directed acceleration is the easy case
Directed acceleration is what it sounds like. The owner asks the contractor to finish earlier than the contract requires, the contractor adds crews, shifts or overtime, and the owner pays the difference.
It is expensive but it is clean. There is an instruction, there is a scope, there is a price, and both parties understood what they were agreeing to.
The owner side questions on directed acceleration are ordinary commercial ones. What is the productivity assumption behind the overtime rate, is the premium portion separated from the base, and what happens if the acceleration does not achieve the date.
That last question is the one most often left open. An owner who pays for acceleration and does not get the date should not also be paying liquidated damages arithmetic that assumes the acceleration worked, and the change order should say so.
Directed acceleration is not the problem. The problem is the other kind.
How a constructive acceleration claim is built
Constructive acceleration has four elements, and an owner can supply all four without ever intending to.
First, an excusable delay occurs. Weather, a differing site condition, a late owner decision, anything for which the contract would grant time.
Second, the contractor requests an extension of time, in accordance with the contract.
Third, the owner refuses the extension, or does not respond, or responds so late that the response is meaningless.
Fourth, the owner continues to insist on the original completion date, usually by pointing at the liquidated damages clause.
At that point the contractor has been placed in a position where it must accelerate to avoid a penalty it does not believe it owes. The costs of doing so become a construction acceleration claim, and the fact that nobody issued an instruction does not defeat it.
The element owners underestimate is the third one. Silence is treated as refusal. An extension request that sits unanswered for two months while the contractor is told the date has not moved produces the same claim as an outright rejection, and a worse record.
Why a construction acceleration claim costs more than the delay
Granting an extension of time costs an owner the extended general conditions and whatever the delay does to revenue.
Acceleration costs the same general conditions for the shorter period, plus overtime premium, plus additional crews, plus the productivity loss that comes from putting more people into the same space.
That last component is the one that turns a large number into a very large one. Trade stacking, out of sequence work and shift work all reduce output per hour, and the reduction is not small. Studies used in claims routinely assert productivity losses of twenty to forty percent on heavily accelerated work, and while the specific percentages are always contested, the direction is not.
So an owner who refuses a 30 day extension worth $400,000 in extended general conditions can receive an acceleration claim of $1.4 million, and the 30 days may not be recovered anyway.
This is why the analysis of whether the delay is excusable matters more than the instinct to hold the date. That analysis is the subject of answering a delay claim.
A worked example
Illustrative figures. Not taken from any client project and not a quotation.
A 300 unit multifamily building. A utility connection is delayed by the provider for 41 days. The contract makes that an excusable delay.
The contractor requests 41 days. The owner, with a lease up date and a lender milestone, does not respond for nine weeks and continues to reference the completion date in monthly meetings.
The contractor accelerates: second shift on interiors, additional drywall and finish crews, weekend work on the exterior.
The claim arrives at completion. Overtime premium $610,000, additional supervision and general conditions $340,000, loss of productivity asserted at 26 percent on affected trades, $1.1 million. Total claimed $2.05 million.
It settles at $1.6 million. The project finishes 12 days late anyway.
Granting the extension would have cost the extended general conditions of roughly $520,000 and the 41 days.
The decision that produced the difference was not a decision. It was nine weeks of not answering.
What an owner should do instead
Answer extension requests on time, in writing, with a reason. An answer that grants ten of the forty one days requested, with the analysis attached, is a defensible position. Silence is not a position at all.
Separate the two decisions. Whether the delay is excusable is a contractual question about cause. Whether you want the original date is a commercial question about money. Deciding the second before answering the first is what creates the claim.
If you want the date, buy it. A directed acceleration with an agreed price, an agreed productivity assumption and an agreed consequence if it fails costs less than the constructive version, because the contractor is negotiating rather than accumulating.
Where a completion date is genuinely immovable, that constraint belongs in the contract at signature rather than in an argument in month fourteen, which is the reasoning behind reading the date before you sign in whether the completion date is real.
Testing the productivity component
The productivity loss line is usually the largest and always the softest, and an owner receiving one should ask three questions before arguing about the percentage.
What is it measured against. A claim that compares accelerated output to the tender allowance is comparing actual performance to an estimate, which proves nothing about acceleration. A claim that compares the accelerated period to the same crew on the same work before acceleration is comparing like with like, and that is a much stronger document.
Which trades are included. Productivity loss from stacking affects trades working in the same space at the same time. A claim that applies a blanket percentage to every trade on the job, including those working in areas nobody else entered, has been calculated rather than measured.
What else was happening. Acceleration rarely occurs in isolation. Where design changes, late releases or weather also fell in the same window, some part of the lost output belongs to them, and the claim should separate it rather than absorb it.
None of these questions requires a scheduling expert. All three narrow the number substantially, and asking them early signals that the claim will be read rather than settled by attrition.
The fourth question is about the crew. A productivity claim asserts that the same work took more hours than it should have. That assertion is testable against the contractor’s own cost records, which show hours booked by trade by week, and a claim that will not produce them is asking the owner to accept a percentage on faith.
An audit right over those records, agreed at signature, costs nothing and is the single provision that most changes how a productivity claim is presented two years later.
What we do
We read the time extension machinery before signature: what counts as excusable, how long the owner has to respond, and what happens to the liquidated damages clause when a request is outstanding. Where a date is fixed by a lease or an opening, we say what holding it will cost under each of those clauses. The work is the schedule and procurement risk review. Where a claim is already on the table, dispute and claims support works from the same records under the direction of your counsel.
Questions people ask
Can a contract exclude constructive acceleration?
Language attempting to exclude it is common and its effect is uncertain, because the doctrine addresses owner conduct rather than an agreed remedy. Relying on a clause to defeat a claim created by refusing a valid extension is a weak position. Answering extension requests properly is a far stronger one.
What if we think the delay is not excusable?
Then say so, in writing, within the contractual period, with the analysis that supports it. A reasoned denial is a defensible act and is the correct response when the delay really is the contractor risk. What creates the claim is not denial, it is denial without reasons or without an answer at all.
Is a no damages for delay clause enough protection?
Less than owners expect. Enforcement varies by state, several jurisdictions read exceptions into these clauses for active interference or bad faith, and some limit them by statute. They also do not apply to the contractor acceleration costs where the owner caused the underlying delay in the first place.
This is general information about construction contracts and is not legal advice.