The goal of this architectural research study is to simulate the thermal performance of a multi-story greenhouse design. To do this, the study must first verify the authenticity of digital simulation, then apply the solver technology to additional designs. It does this in three phases: The first is a quantifiable, measurable field investigation which will lead to conclusions about the varying temperatures surrounding a greenhouse facility. The study data describes a distinct difference in temperature between the interior and exterior, demonstrating a clear control of the internal environment across all weather conditions. The second phase of the study simulates the greenhouse's performance in Autodesk CFD using comparable conditions as found in the first phase. The resulting simulation data has minimal deviation from reality: 92% of the results were within 10 degrees F of the actual recorded data. In the third and final phase of the study, CFD is used to evaluate the thermal performance of three new designs. This provides an incredible amount of insight into the impact of design factors such as massing, HVAC placement and solar orientation. This study attempts to prove that digital simulation can accurately predict the thermal performance of a design. Based on the success of the three phases, it can be concluded that CFD has the ability to reflect reality in a consistent and accurate manner.