The use of protected agriculture has seen an increase due to the high demand for high quality products, especially out of season. Greenhouses are used during winter months to ensure improved environmental conditions for plant growth. The correct temperature for optimum plant production can be achieved by utilizing heating systems in the greenhouse. The use of heating systems has a substantial impact on the cultivation time, quality and quantity of the crop production. Greenhouse heating systems are generally used to increase the thermal energy storage inside the greenhouse during the day [1]. In general, greenhouses are heated by circulating hot water in pipes, or by distributed hot air in ducts. The greenhouse in this specific study contains hot-water pipes. Certain parameters must be taken into account when designing a greenhouse heating system. An important factor to consider is the placement of the pipes. It has been recommended that the temperature at plant level be uniform throughout the greenhouse [2]. The main objective of the research conducted in this paper is to numerically investigate the design effect of the use of hot-water pipes on the indoor climate of a confined greenhouse using Computational Fluid Dynamics (CFD). The influence of the distance between the hot water heating pipes is also investigated. The initial two-dimensional greenhouse cavity simulated using CFD is validated against experimental results found in the literature. The numerical model is then modified to represent a greenhouse containing benches and water heating pipes. CFD software is used to analyze the velocity and temperature distributions for the greenhouse in terms of graphs and parametric contour plots. To determine mesh independence, a mesh sensitivity analysis has been conducted. Initial results show a significant influence on the temperature and velocity distribution inside the greenhouse. The results of this study may be utilized by small greenhouse growers to support better crop production.