This major research project focuses on reducing the energy consumption, by modelling a radiant floor heating system with phase change materials, in the Toronto climate. Computer generated simulations were performed using DesignBuilder software, using an example of a typical condominium in Toronto .Two south facing suites and two north facing suites were investigated. Of those suites, one north facing suite had PCM below the finished floor, as well as one south facing suite. The objective of these simulations was to determine the impact of using PCM in the condo suites. Three different types of PCM were used, in order to determine which type had the biggest energy savings. The PCMs were M91/Q21, M51/Q21 and M27/Q21. The final results showed that the suites with the M27/Q21 PCM had the lowest energy usage. A cost savings comparison was performed based on the rate of energy used and the cost of the energy, provided by the Ontario Energy Board.