Housebuilders could make cost savings of almost £800 per dwelling and could achieve at least a Code level three rating, by utilising sustainable technologies beyond the conventional. <br> <br> Research by Passivent, the natural ventilation specialist, reveals that under changes to the SAP calculation method, installation of even its basic Passive Stack Ventilation system (PSV) in conjunction with a gas saver, waste water heat recovery and photovoltaic equipment can achieve capital cost savings of up to £780 per dwelling, and achieve an improved DER (dwelling emission rate) against the widely-accepted route of MVHR (mechanical ventilation with heat recovery). <br> <br> Under Passivent’s analysis, on a four-bedroom semi-detached home with three wet rooms and an airtightness of three, the PSV with gas saver and waste water heat recovery required just 0.82kW per hour of PV (photovoltaics) to achieve Code level three, and cost less than £4,000 for all of the technologies.<br> <br>