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    Extension SAP calculations need to be completed on a building extension that has glazing for more than 25% of the floor area.
    On completion of your SAP calculation you will receive and EPC certificate showing you have complied with building regulation and have passed part L1B of building regulations.

    Standard Asssessment Procedure
    Calculations Explained

    The carbon output is increased where there are areas of extensive glazing. This is due to heat the increase in heat loss. To counteract this increase in carbon output and reduce any unnecessary heat loss, certain building alterations can be implemented. 

    Installing solar panels to the exterior of the building could be used as an example of a method of balancing out the increased carbon loss. This modification to the design of the proposed extension would provide enough remedial work to pass the SAP calculation.

    With multiple years of combined experience dealing in SAP extensions, our assessors will be able to provide you with the most cost effective and time saving approach to passing your SAP calculation.

    What our
    Standard Asssessment Procedure
    Assessors need from you

    For our assessors to prepare and complete your buildings SAP calculations we will need to gather the following drawings and specifications from you;

    ​Drawings for proposed & existing dwelling;
    • Elevation, section drawings

    • Floor plans

    • Site plans

    • Windows: incl. frame material, width of gap & emissivity of glass

    • Doors: incl. frame material & width of gap

    • Heating & Cooling

    • Ventilation system

    • Hot water system: cylinder size & controls

    If there is anything you feel unclear about or you simply want to speak to one of our team members, don’t hesitate to give our office a call.