New England residential buildings require higher energy consumption. Additionally, air quality is inhibited in colder months as people reduce ventilation to maintain a comfortable temperature. This leads to the accumulation of CO₂, volatile organic compounds (VOCs), and particulate matter (PM2.5) in potentially harmful amounts. Also, radon is common among basements and carries potential health hazards, as the soil is one of the factors that support its formation. This research uses simulations and field tests to determine residential building energy consumption, indoor air quality, and radon concentrations. Revit and Climate Studio were used for energy performance simulation to estimate thermal loads, identify possible issues, and mitigate the concentration of these harmful chemicals. The final objective of the research is to confirm that computer simulations can match conditions found in the field.