Construction contracts, especially those using standard forms, commonly include a differing site conditions clause allowing a contractor to recover extra cost and time if it encounters subsurface or latent conditions that either materially differ from what the contract documents represented (a Type I claim) or are unusual and materially different from conditions ordinarily encountered in the type of work (a Type II claim). Without such a clause, a contractor bears the risk of unforeseen conditions under the common-law default rule, making the clause's presence and wording central to the dispute.

Litigation typically turns on whether the contractor gave timely notice upon discovering the condition, whether the condition was actually concealed or unknown rather than discoverable through a reasonable pre-bid site investigation, and whether the owner's own boring logs, geotechnical reports, or plans affirmatively represented different conditions. Owners often defend by arguing the contract disclaimed reliance on subsurface data or that the contractor should have discovered the condition during its own due diligence.

Because a differing site conditions claim usually spawns both a time-extension request and a cost claim, Juricratic tracks it as a coupled two-dial branch, letting the user separately weight the probability of entitlement (was this really a differing condition) against the probability the quantum claimed will be sustained, since the two frequently diverge.

Contractors document differing site conditions in real time with photographs, daily logs, and prompt written notice to preserve the claim, while owners and design professionals compare the contractor's evidence against the geotechnical data furnished at bid time to test whether the condition was truly unforeseeable or should have been anticipated.