With LiDAR becoming a common occurrence on smartphones, tablets; Capturing and rendering an accurate structure of our house in 3D can be done in minutes. This removes a major friction in building simulation for home consumers i.e. constructing the building virtually(Large building planners have been using 3D simulation for decades).
Adding ventilation simulation to it can enable anyone to plan ventilation in their building. Say like after scanning the app suggests to make changes to the placements of ventilation duct, Windows, moving large structures which can obstruct air flow etc.