If you are undertaking a conversion of an existing building, the initial SAP Calculations must be prepared at design stage for the property and submitted to local building control before any development work commences.
Once the conversion works have been completed an as-built SAP Calculation is prepared and will incorporate any design changes that have occurred along with the finalised details regarding heating, hot water and ventilation systems that have been installed.
The finalised SAP Reports are then produced for submission to building control together with an On Construction Energy Performance Certificate (EPC) which is required by building control prior to the issue of the completion certificate and also for the subsequent sale or let of the property.