I"ve just received two completetly diferent suggestions for dealing with a crawl space. One is incapsulationwith a type of drain sytem the other is to let air move freely through vents to exterior. Vents are designed to open and close with temperature changes. Both companies do basement wall and foundation repair work and where recommended by a structursal engineer.
Who is correct herea? Where is the science for one or the other coming from?