Jacob &amp; Youngs, Inc. v. KentJacob &amp; Youngs, Inc. v. Kent Jacob & Youngs, Inc. v. Kent Jacob & Youngs, Inc. v. Kent, 230 N.Y. 239 (1921) is an American contract law case of the New York Court of Appeals with a majority opinion by Judge Benjamin N. Cardozo. It dealt with the matters of material breach and substantial performance. Facts. The plaintiff built a house for the defendant under contract. The defendant learned that some of the piping, instead of being made by the Reading Iron Company ("Reading Pipe"), was made by the Cohoes Rolling Mill Company ("Cohoes Pipe"), which was contrary to one of the explicit terms in the contract. The  defendant asked the plaintiff via the architect to do the work all over again supported by the perfect tender rule. Because the pipes had already been encased within the walls except in a few places where it had to be exposed, to replace the "Cohoes Pipe" with the contracted-for "Reading Pipe" would have meant more than the substitution of other pipe. The plaintiff would have had to demolish, at great expense, substantial parts of the completed structure. The plaintiff left the work untouched, and asked for a certificate that the final payment was due (arguing substantial performance) which was  refused by Kent. Jacob & Youngs then filed suit to collect the remaining balance. The trial court ruled in favor of Kent, which was reversed on appeal and a new trial was ordered. Holding. The plaintiff builder won and obtained a monetary judgment. Plaintiff did not have to replace the Cohoes pipes with the Reading pipes. Significance. When the defect is insignificant, the court will find that there was substantial performance and will excuse the breach of using the same type and quality of pipe which parties had agreed were the same except for brand name. Measure of damages is not  the cost to rip out the old pipe and install the new, but the difference in value which in this case is zero dollars. Jacob & Youngs, Inc. v. Kent Jacob & Youngs, Inc. v. Kent, 230 N.Y. 239 (1921) is an American contract law case of the New York Court of Appeals with a majority opinion by Judge Benjamin N. Cardozo. It dealt with the matters of material breach and substantial performance. Facts. The plaintiff built a house for the defendant under contract. The defendant learned that some of the piping, instead of being made by the Reading Iron Company ("Reading