Poorly-designed HVAC ducts can significantly impact indoor air quality in buildings. Inadequate duct sizing, improper sealing, or poorly positioned vents can lead to inefficient airflow, resulting in uneven temperatures and insufficient ventilation. This may create stagnant air pockets, leading to increased levels of dust, allergens, and pollutants. Inefficient filtration and inadequate insulation can also contribute to poor indoor air quality. To ensure a healthier living or working environment, it is essential to invest in well-designed HVAC duct systems that promote proper airflow, ventilation, and effective air filtration.