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Mechanical Ventilation
STRUCTURE & PHYSICSbeginner
Definition
The use of fans and ductwork to move fresh air into and stale air out of a building. In well-insulated modern buildings, mechanical ventilation is essential because airtight construction prevents accidental air infiltration. Mechanical Ventilation with Heat Recovery (MVHR) reclaims heat from outgoing air to pre-warm incoming fresh air.
Example
Every certified Passive House building must include an MVHR system — typically recovering over 80% of the heat in exhaust air — making mechanical ventilation a key component of achieving near-zero energy demand.