Contracts

What are concealed conditions in construction?

Concealed conditions are physical conditions at the site that were hidden when the contract was signed and turn out to differ from what the contract documents showed or what a contractor would normally expect.

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Concealed conditions are the surprises behind the drywall, under the slab, or below grade: rotted framing, an abandoned oil tank, unmarked utilities, rock where the borings showed clay, or an old structure that does not match the drawings. Most contracts treat them as a risk the owner carries, through a concealed conditions or differing site conditions clause, as long as the contractor gives proper notice. Without that clause, the contractor may be stuck with the cost.

The two types most contracts recognize

The federal clause at FAR 52.236-2 is a good model because many private forms follow similar logic. It covers (1) subsurface or latent physical conditions that differ materially from those indicated in the contract, and (2) unknown physical conditions of an unusual nature that differ materially from those ordinarily encountered in that kind of work. Lawyers call these Type I and Type II conditions.

  • Type I: the drawings show one thing and you find another. The geotech report shows no groundwater at 8 feet and the excavation floods at 6.
  • Type II: the documents are silent, but what you find is unusual for this kind of work. A remodel of a 1980s house reveals a buried concrete vault no one would expect.

Notice is everything

FAR 52.236-2 requires written notice to the contracting officer promptly, and before the conditions are disturbed. It also says no adjustment is allowed unless that notice was given (the contracting officer may extend the time), and no request is allowed after final payment. Private contracts often set a specific number of days. Whatever the form, the pattern is the same: stop, photograph, notify in writing, then proceed as directed.

Worked example

A remodeler is opening a bathroom wall on a $72,000 renovation and finds the subfloor and two joists rotted from a long-term leak. The super stops work in that area, takes photos with a tape measure in the frame, and sends the homeowner a written notice that day. The change order request prices the repair at $4,800 and two extra days. Because notice went out before the framing was cut out, the homeowner can see the condition for themselves, and the change order is signed in two days. Had the crew fixed it first and asked later, the remodeler would be arguing over photos of new lumber.

Common disputes

  1. Should you have known? Owners argue a reasonable site visit or the documents provided would have revealed the condition.
  2. Disclaimers. Contracts that say borings are "for information only" or make the contractor responsible for verifying everything can undercut a claim.
  3. Late notice. Work done before notice is the most common reason a valid condition goes unpaid.
  4. Pricing. Even when the owner accepts the condition, the cost and time are often argued, so track the extra labor and equipment separately in your daily log.

Related terms

See notice of claim and delay claim. The guide how to handle differing site conditions claims walks through the notice and backup step by step. Smart Business Automator lets the field log a condition with photos and route it straight into a change order for approval.

Frequently asked questions

Are concealed conditions the same as differing site conditions?

Largely, yes. "Concealed conditions" is the phrase used in some private contract forms, and "differing site conditions" is the federal term. Both deal with hidden physical conditions that differ from what was expected.

Who pays for concealed conditions?

If the contract has a concealed or differing conditions clause and the contractor gives proper notice, the owner usually pays for the added cost and time. Without such a clause, or with strong disclaimers, the risk may sit with the contractor.

How fast do I have to give notice?

Check your contract. The federal clause requires prompt written notice before the conditions are disturbed. Private contracts often set a specific number of days.

Do concealed conditions apply to residential remodels?

They come up constantly in remodels. A good residential contract includes a hidden conditions clause that explains how discoveries will be priced and approved.

Sources

  1. Acquisition.gov: FAR 52.236-2 Differing Site Conditions
Written and edited by

Maurice Francois writes and edits construction operations guides for Smart Business Automator. More from Maurice on the Scaling Legends podcast.

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