To enhance the throughput and Quality of Service (QoS) of indoor users, Femto cells became the best solution. The placement of a femtocell is always a challenging task due to its interference constraints with other cells. If the base stations has limited number of Femto-cells, then there is need to focus much on interference constraints. In the dense countries like India, there is a need to install more number of Femto-cells to get the proper throughput. But, the limiting factor here is frequency and interference management. This paper explained the interference management issues and hand over issues. This paper proposed method of optimal placement of Femto cell to increase the QoS in dense environment where macro-cell holds many number of Femto cells. This solution made an assumption that the interference effect was considerably strong when compared to Noise. Hence, we have not considered Noise parameter in the analysis. It was shown that the optimal placement has better throughput when compared to blind placement. Two cases were considered as blind placements and their throughput was analyzed with respect to optimal placement. The proposed method was tested in both single and multi-room buildings. Finally, it was observed that the gain of 50% was increased with respect to large buildings with many rooms.