Construction contracts · Completion, payment and warranty deadlines
Substantial completion, liquidated damages, and every date that runs from the notice to proceed.
A construction contract fixes almost nothing as a calendar date. Substantial completion is “540 days after the Commencement Date”, liquidated damages start “on the first day after the Grace Period ends”, the first payment application is due on the 25th of the first full month after commencement, and the Commencement Date itself lives in a certificate signed later. Prism reads the rules and the certificate, computes each date in code, and returns it with the clause it came from.
What comes back
Sample rows from a guaranteed maximum price contract we wrote for this page, with a Notice to Proceed of April 29, 2026, a Mobilization Date of May 11 and a Commencement Date of May 18, all fixed by the Commencement Certificate.
| Date | What it is | How it was found | The clause |
|---|---|---|---|
| May 4, 2026 | Certificates of insurance due before mobilization | Computed: 7 days before the Mobilization Date, May 11, 2026, not before the Commencement Date | “not later than seven (7) days before the Mobilization Date. Contractor shall not mobilize onto the Site until the certificates and endorsements have been received by Owner.” |
| May 18, 2026 | Commencement Date | Stated in the Commencement Certificate; the body of the contract says only that the Notice to Proceed will state it | “The Commencement Certificate, when signed, is part of this Contract and fixes those dates for all purposes of this Contract.” |
| Jun 25, 2026 | First Application for Payment due | Computed: the 25th of the first full calendar month after May 2026, then the 25th of each month | “beginning with the twenty-fifth (25th) day of the first full calendar month after the calendar month in which the Commencement Date occurs” |
| Nov 9, 2027 | Scheduled Substantial Completion Date | Computed: the 540th day after May 18, 2026. The summary of key terms says "18 months", but the contract says Article 5 controls | “achieve Substantial Completion within five hundred forty (540) days after the Commencement Date (the "Contract Time")” |
| Nov 20, 2027 | Liquidated damages begin to accrue | Computed: the first day after the 10-day Grace Period that follows November 9, 2027. Neither November 10 nor November 19 | “Liquidated damages begin to accrue on the first day after the Grace Period ends, and if Substantial Completion is achieved during the Grace Period no liquidated damages are payable.” |
| No date yet | Last day to notify a warranty defect | Not yet dated: one year from the actual Substantial Completion stated in the certificate, plus 30 days, and the certificate has not been issued | “The Warranty Period runs from the date of Substantial Completion stated in the Certificate of Substantial Completion, and not from the Scheduled Substantial Completion Date.” |
The rows are from a contract we wrote for this page, not a customer’s. Every result also carries what happens if the date is missed and the page it is on. How often Prism finds these dates is on the accuracy page.
What Prism looks for
Notice to proceed, mobilization and commencement
The three start dates, taken from the certificate that fixes them rather than the body that only promises them.
Substantial completion and the contract time
The scheduled date counted from commencement, and the change orders that add days to it.
Liquidated damages and grace periods
The first day damages accrue, after any grace period the contract gives, and the daily amount, quoted.
Payment applications and owner payment
The day of the month each application is due, and how long the owner has to pay after receiving a complete one.
Retainage
The percentage withheld, the point at which it reduces, and when it must be released after final completion.
Change-order and claim notices
How many days the contractor has to give notice of a change event, and to submit a claim, before the adjustment is waived.
Punch list and final completion
The inspection request, the punch list completion period and the final completion deadline after substantial completion.
Warranty and insurance
The warranty period, the window to notify a defect, and the certificates due before mobilization and before each policy expires.
What it will not do
Prism returns what the contract states and quotes where. It does not decide whether a delay was excusable, does not count a period stated in business days (that is returned with its rule and left for you to date), and does not fill in a term the contract leaves out. A date that runs from an event that has not happened, such as actual substantial completion, is returned with its rule and left undated. It is not legal advice, and reminders are best-effort.
Use it from an AI agent
Prism is a remote MCP server. In Claude Code:
claude mcp add --transport http prism https://prism.parad1gm.com/api/prism-mcpThen ask: “Read this construction contract and list every deadline counted from the notice to proceed or the commencement date, with the clause each one comes from.” The agent sends the document with prism_review_contract and reads the result with prism_get_contract. Setup for Claude on the web, Cursor, VS Code and A2A agents is on the agents page.
$0.50 a contract for an agent, and the first 3 are free. On the website it is $1 per contract, or $9 a month for up to 50.
Questions
Where does the commencement date come from?
From the Commencement Certificate or notice to proceed when the contract has one, because the body usually says only that the notice will state it. Every date counted from commencement is then computed from that certificate date.
The summary says 18 months but the article says 540 days. Which wins?
The one the contract says controls. Where a summary of key terms disagrees with an article and the contract says the articles govern, the article is used. Eighteen months and 540 days differ by nine days here, and the difference is the point.
When do liquidated damages actually start?
On the first day after the grace period, if the contract gives one. The scheduled completion date, the last grace day and the first damages day are three different dates, and Prism returns the right one with the clause that sets it.
What does a change order do to the dates?
Send it with amendsContractId, or add it from the contract on the site. It is read together with the contract, so days added to the contract time move substantial completion and the start of liquidated damages with it, and the superseded dates are left out.
Why is the warranty deadline undated?
Because it runs from actual substantial completion as stated in the certificate, which has not been issued. Prism returns the rule and leaves the date empty rather than assume the scheduled date will be met.
Is this legal advice?
No. It tells you what the contract says and where. Before you rely on a notice period or a damages date, read the clause it quotes and ask a lawyer.