(dissenting).
Reindl and Fullerton entered into an oral agreement whereby Fullerton would supply the materials to build a building in accordance with Reindl’s design. Testimony reflects that Reindl’s chief desire was to obtain an inexpensive building. Instead of purchasing or having constructed a hog farrowing barn, Reindl decided to build a 24' by 72' pole shed sheeted with corrugated steel. Reindl independently chose an unorthodox roof design which was essentially flat because it was cheaper than the type of roof customarily installed on farrowing barns. Reindl privately and separately contracted with third parties for electrical work, a heating system, and plumbing. Collateral to the agreement between Fullerton and Reindl, Fullerton sought and obtained the services of one Myron Lang for the purpose of assembling the building per the design of Reindl. Fullerton furnished the materials for the frame, siding, and roof of the building. Once again, acting as his own general contractor and architect, Reindl separately contracted with the said Myron Lang to pour and finish all concrete work for the building.
The trial court found that the building was constructed in a good workmanlike manner and the materials employed in the construction of the building were without defect. Several months after the building was completed, the roof began to leak. The trial court found that, indeed, the roof leaked and that the leakage was the result of the defective design. The majority opinion and I part company on the responsibility of the defective design. When an essentially flat roof on a structure is constructed in a good and workmanlike manner in conformance with the design furnished by the owner, the contractor is not liable to the owner for damage resulting from water leaking into the building due to the defective design. Sunbeam Construction Co. v. Fisci, 2 Cal.App.3d 181, 82 Cal.Rptr. 446 (1969). The majority opinion fails to recognize this rule of law, and to apply it to this set of facts, as did the trial court. For further analysis to support this dissent, see generally, Annot., 6 A.L.R.3d 1394 (1966). As for South Dakota case law, I believe Reif v. Smith, 319 N.W.2d 815 (S.D.1982), is dispositive of this case. We held in Reif that a contractor who follows the design supplied by the building owner is not responsible for damages due to the design, unless the contractor was negligent or expressly warranted the design. Negligence on Fullerton’s behalf was neither pled, proved, or found by the trial court. Reindl conceived of the unusual design for his hog farrowing barn with the goal in mind of saving on construction costs. He chose a pole shed building. South Dakota’s climate, affected by its latitude, elevation, terrain, and remoteness to mild ocean air, does not permit the farrowing out of hogs in a pole shed building on an all-year-round basis. Put another way, little pigs die when they become cold and wet. Hog farrowing barns, so that pigs are safely born with adequate protection during varying seasons, have become sophisticated and expensive. Reindl knew this. Reindl solicited price quotations for materials to build this barn and he chose Fullerton to do the job. In summary, the evidence reflects that Reindl conceived of a shortcut to farrow out sows in a cheap building, he designed a cheap building, he paid for a cheap building, and he got a cheap building. Having found out that his cheap building design did not hold up to the elements of South Dakota’s climate, he literally seeks in law to impose the costs of improving this cheap building and the burden of his swine losses while using it, on Fullerton.
Not for one minute do I accept the legal conclusion that under the state of this record, Fullerton warranted Reindl’s design as producing a good hog farrowing barn. Nor do I accept the trial court’s finding that *298“Fullerton approved” the design. The trial court hung its hat on such a theory and it is unsupported in fact. The design was the concept of Reindl and it was Reindl who approved it and insisted upon it. On direct examination, Don Werley, the manager of Fullerton Lumber, testified that he told Reindl of possible leakage problems:
Q. Now, to the best of your recollection, Mr. Werley, relate to the Court the conversation in as much detail as possible that you had with Mr. Reindl when he first talked to you about this building.
A. When he first came in, he was talking about his father — him and his father had just built a calf shelter in the yard, and he wondered if the same type of building could be used for housing hogs.
We talked about it, commenting on whether the 24-foot span would be too great. And I told him I was real afraid that snow would take it down, and, also, the fact that it was an awful low pitch to drain water. (Emphasis supplied.)
Later, in cross-examination, Mr. Werley was confronted with his deposition statement that Mr. Werley only mentioned the snow load problem with Reindl. Mr. Wer-ley reaffirmed his statement that he told Reindl of possible leakage problems and noted that during his deposition he was responding to a question regarding structural problems rather than drainage problems with the pole shed building. I find the trial court’s findings of facts and conclusions of law clearly erroneous and I am of the definite and firm conviction that a mistake was made at the lower court level.
Under the lower court and the majority opinion’s holding, Reindl recovers for 60 pigs which died in the spring of 1976 of a value of $1,875; and likewise, Reindl recovers $855 for 30 pigs which died in the spring of 1977. This totals $2,730 damages for a leaking roof designed by Reindl. Now, mind you, Reindl himself testified that he used this pole shed building as a hog farrowing barn from the spring of 1976 through the spring of 1981. Lo and behold, he further testified for each year he used the building, he experienced problems with a leaking roof, and as a result, his pigs would die. Yes, Reindl testified that he repeatedly contacted Fullerton requesting that Fullerton fix the leaking roof (rather than to crawl up upon the roof and fix it himself). I submit that when the roof leaked, it behooved Reindl to repair the leak and to not suffer more little pigs to perish in this pole shed building that was inadequately designed. Reindl did not mitigate his damages. Everyone owes a duty to exercise some common sense. When Reindl testified that he lost 30 pigs each time his sows farrowed, once in April and once in October of each year (spring of 1976 through the spring of 1981), I submit that poor judgment was exercised and that this lumber company should not be responsible for the loss of any of Reindl’s poor judgment and failure to mitigate his damages. As we correctly quoted many years ago in Gardner v. Welch, 21 S.D. 151, 157-8, 110 N.W. 110, 112-3 (1906):
“The law imposes upon a party injured from another’s breach of contract or tort the active duty of making reasonable exertion to render the injury as light as possible. If, by his negligence or willfulness, he allows the damages to be unnecessarily enhanced, the increased loss, that which was avoidable by the performance of his duty, falls upon him. This is a practical duty under a great variety of circumstances, and, as the damages which are suffered by a failure to perform it are not recoverable, it is a duty of great importance.” 1 Sutherland, 148.
See also, Stadheim v. Becking, 290 N.W.2d 273 (S.D.1980).
I note that this Court further affirms the trial court on an award of damages for breach of contract in the amount of $1,728. This figure represents the purported reasonable costs of repair to the roof. It logically follows that since Reindl designed the roof, Fullerton should not be responsible for repairing Reindl’s defective design. This is particularly true in light of the testimony that Reindl was apprised that there would *299be drainage problems because of the roof’s design.
Damages awarded for the repair of the roof approximate one-third of the cost of this building. Considering that Reindl recovers $2,730 for damages for lost baby pigs, Reindl ends up with a 24' by 72' building on his farm for virtually nothing. I consider this manifestly unjust. An owner who instructs that an inexpensively designed real estate improvement be made does not bargain for and is not entitled to receive an optimal improvement such as would be designed by an experienced engineer, therefore, the owner is not entitled to recover from the contractor anything beyond what the contract called for, a less than optimum structure. Oakwood Villa Apartments, Inc. v. Gulu, 9 Mich.App. 568, 157 N.W.2d 816 (1968). Whatever happened to the old adage “You get what you pay for”?