Book in your SAP calculation now. We aim to complete your SAP in a 48 hour time period.

Call us on

Email us at


    A SAP calculation is required for all building conversions where a change in building materials has taken place in order to pass building regulations. The size of  the conversion may range from a large industrial unit being turned into flats, or a small loft conversion. What ever the size, we can provide the relevant SAP calculations you need.

    What is a Material Change
    to a building

    • The dwelling contains a flat where it previously did not.

    • The dwelling is used as an institution, where previously it was not.

    • The dwelling is used as a shop, where previously it was not.

    • The building contains a room for residential purposes, where previously it did not.

    • The building, which contains at least one dwelling, contains a greater or lesser number of dwellings than it did previously.

    For you to receive an EPC you must comply with building regulations to show that the building standards have been met. By completing a SAP calculation you are proving evidence to building standards that compliance has been achieved. 

    Why is it required?

    It all boils down to the health of the building’s occupants. Builders have become comfortable with the requirements for achieving low air test scores, but this has increased the necessity to ensure correctly sized purpose ventilation systems are installed – which function as they should do. It’s all well and good to have a nice air-tight build which achieves a great air leakage score, but it needs to be properly ventilated or people will have breathing difficulties.

    What’s more, if an extract unit is installed in a place where a lot of water vapour and pollutants are released, it needs to be removed to stop the spread to the rest of the building. Long-term impacts of dampness and mould can have serious effects on a person’s health, as we touched on in this article:build tight, ventilate right.

    What we need from you?

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

    • Elevation drawings
    • Floor plans
    • Section drawings
    • Site plans
    • Door specifications
    • Heating specifications
    • Ventilation specifications
    • Glazing specifications
    • Lighting specifications

    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.