When an extension needs SAP
Extensions with glazing above the normal elemental allowance may need a SAP assessment to show that the proposed design performs no worse than a compliant reference extension. We confirm the appropriate calculation route from the drawings and Building Control comments.
Test the design before it is fixed
We model the extension, existing dwelling, glazing, fabric and heating arrangements so the impact of larger doors, rooflights and open-plan layouts is understood early. Practical options can then be tested without defaulting to unnecessary specification increases.
A clear Building Control submission
The completed assessment explains the method, assumptions and comparison result in a format suitable for the project team and Building Control. Where needed, we coordinate supporting U-value calculations and revised specifications.