The plaintiff was renovating it hog facility and contracted with the defendant to install infrastructure needed to provide the building with liquid propane gas. Another defendant was contracted with to install gas lines from exterior walls throughout the interior of the building to connect heaters and other devices. An employee of one of the contractors connected the external gas lines to the building. Later, the new ventilation fans were turned on and within two hours the building caught fire. The plaintiff sued the contractors for negligence and also sought a jury instruction on res ipsa loquitur. The trial court refused to issue the instruction and the jury ruled for the contractors. On appeal, the court affirmed. The court noted that the plaintiff failed to prove that the cause of the fire was under the defendants' exclusive control. However, the court mistakenly stated that where "as here, the cause or instrumentality giving rise to the injury is unknown, the doctrine of res ipsa loquitur is simply inapplicable." In fact, it's precisely the opposite. However, the court managed to stumble into the right result. The pleading of negligence precludes the ability to also plead res ipsa loquitur. The presence of the evidence of negligence bars a res ipsa claim. TAMCO Pork II, LLC v. Heartland Cooperative, No. 14-0412, 2015 Iowa App. LEXIS 629 (Iowa Ct. App. Jul. 22, 2015).