In Ireland and globally, a primary concern is whether retrofitted houses perform as promised to provide occupants with better indoor environment quality (IEQ), which may affect their satisfaction and health. Although there has been growing interest in the performance of retrofitted residential buildings, a post-occupancy evaluation of performance is required as evidence of improvements. I am evaluating the performance of 100 Galway homes based on indoor temperature, humidity, and CO₂ levels. All selected homes possess a Building Energy Rating (BER) of A2 or better, aligning with stringent energy-efficiency standards. These homes are scored based on the continuous monitoring of daily average temperature and relative humidity over a duration of at least twelve months to assess compliance with established comfort zones (Temperature: 18-24°C, RH: 40-60%, and CO₂: <1000 PPM). In addition to the scoring assigned based on meeting the comfort standards, Time of Wetness (TOW) is calculated to evaluate the risk of mould development. The results of this study can be helpful in evaluating building performance, particularly when energy savings are contractually guaranteed. It underscores the importance of monitoring the indoor environment post-occupancy to ensure that energy efficiencies do not compromise the indoor climate. Building owners, Energy Service Companies, and local authorities will benefit from such type of assessment framework, as it will provide a concise, single-page assessment of building performance and contractual terms.