Abstract: A ventilation system for regulating atmospheric communication between a first space and a second space includes an airflow regulation device and a control system. The airflow regulation device is disposed in fluid communication with the first and second spaces. The airflow regulation device includes a regulator for regulating airflow and an adjustment system connected to the regulator for adjusting the regulator. The control system includes a first sensor, a second sensor and a microcontroller. The first sensor is in fluid communication with the first space to measure a first atmospheric condition. The second sensor is disposed in fluid communication with the second space to measure a second atmospheric condition. The microcontroller is in communication with the first sensor and the second sensor for comparing the atmospheric conditions. The microcontroller is in communication with the adjustment system for adjusting the regulator in response to differences between atmospheric conditions.

Abstract: A duct assembly for disposition in an attic of a building includes a first vent and a duct. The first vent defines an opening for fluidly communicating with air in an exterior of the building. The duct includes an elongated side defining a passage. The elongated side extends between a first end and a second end with the first end coupled to the first vent and with the passage in fluid communication with the opening of the first vent. The duct includes an end plate sized larger than the passage and sealed to the second end covering the passage at the second end. The elongated side includes an unperforated portion being unperforated and a perforated portion defining a hole for providing fluid communication from the opening of the first vent to the hole.

Abstract: A system and a method are described for maintaining a first pressure of a first portion of a building below a second pressure of a second portion of the building to prevent moisture from migrating from the first portion to the second portion. The system may include a pressure measuring system, an exhaust air mover, and a microcontroller. The pressure measuring system, e.g., a differential pressure sensor, may be selectively operable to calculate a pressure difference value between the second pressure and the first pressure. The exhaust air mover, e.g., a fan assembly, may be adjustable for selectively varying exhaust of air from the first portion to an exterior of the building. The microcontroller may be in communication with the pressure measuring system and the exhaust air mover to instruct the exhaust air mover to increase or decrease the exhaust of air to maintain the pressure difference at a positive setpoint.