Independent research commissioned by Passivent, the domestic natural and mechanical ventilation supplier, has highlighted that amendments to the SAP calculation tool and requirements under Part F mean that Passivent’s standard passive stack ventilation (PSV) system can cut initial installation costs by more than half, reduce the DER (dwelling emission rate) under SAP, and contribute towards an 83% saving in lifetime costs – whilst still helping achieve up to Code level six. <br> <br> Passivent’s PSV is the only domestic ventilation strategy that uses no electricity to function. It harnesses natural air movement principles, like a chimney, to ensure the home is adequately ventilated every day. Passivent PSV uses planned air paths to exhaust warm, “used’ internal air out through the roof terminal, creating a natural draught-free “suction” effect to stimulate replacement with fresh air through strategically positioned inlets. It therefore requires no operator input, cannot be switched off, is silent in operation, and has no moving parts to service or replace.<br> <br>