SAP Calculations for Conversions

SAP Calculations for Conversions

If your project aims to develop a new dwelling from an existing one, convert a single dwelling into self contained flats, or even convert a commercial property into a dwelling, then you will likely require a Part L1b SAP Calculation (or a regional variation) to satisfy Building Regulations/Standards.

Whatever the size of your project, Elmhurst Energy Consultancy can complete SAP Calculations to ensure your conversion complies with the Building Regulations/Standards for your area. 

When are SAP Calculations for Conversions required?

A SAP Calculation would be required for all new dwellings created as a result of a 'Material Change of Use' or 'Change of Energy Status'.  

Material Change of Use

Material change of use occurs where there is a change in the purposes for which, or the circumstances in which, a building is used.

Typical examples of material changes of use include: 

  • where after the change, the building is used as a dwelling where previously it was not;
  • where after the change, the building contains a flat, where previously it did not
  • where after the change, the number of dwellings in a building is changed

Change of Energy Status 

A change in energy status will occur where a previously unheated space/building is designed to be heated in the future. A material change of use will also likely change the energy status of a building.


Elmhurst Energy Consultancy and SAP Calculations for Conversions

Unlike typical SAP Calculations, conversion calculations in SAP do not require DER/ TER (Emission Rate) calculations, as compliance for energy efficiency standards is based on controlled services/fittings as well as new, replacement, or retained, thermal elements.

Conversion calculations in SAP are advised as we can produce a valid Energy Performance Certificate (EPC) as required for a new conversion.

This basis for compliance can be stringent, however our expertise with SAP Calculations and Building Regulations/ Standards ensures we can tackle any issues quickly and find suitable solutions for our clients.


What we do to ensure compliance

To ensure compliance is met for conversions, we produce U-Values within our SAP Calculations to check if they meet the requirements provided in the technical booklets and approved documents provided by government. If these values are too high or do not meet the standards, then we will give advice to the client as to how they can be achieved.

We also ensure all lighting levels and heating systems meet the minimum requirements and, if not, we will advise you of the necessary steps to ensure that the requirements are achieved. 

Call us now on

01455 883 259

 and discuss your project with us, there’s no obligation and we’re happy to advise you.

Or why not complete our 'Get a quote' form




Related Links

SAP Calculations >SAP Calculations for Extension >SAP Calculations for New Builds >

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