You can buy heat exchangers with very high efficiency and good moisture reclamation or suppression for a slightly higher cost. The problem is usually that the c

You can buy heat exchangers with very high efficiency and good moisture reclamation or suppression for a slightly higher cost. The problem is usually that the customer does not look into the details and the construction company can increase profits by buying cheaper versions. A good modern ventilation energy exchange unit for a 300m2 house can be <30dB, >90% efficiency, and return a lot of humidity.