Self Builders

Self Builders and Energy Efficiency Compliance 

What are SAP Calculations? Why do I need them? What is an Energy Performance Certificate?

Elmhurst Energy Consultancy has worked alongside many self builders to help them through the minefield that is Building Regulation/Standards compliance. There is no project too big or too small, and our services are provided to self builders across the UK.

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About SAP Calculations

You may or may not have heard about Standard Assessment Procedure (SAP) or SAP Calculations throughout the building process. It can be difficult for Self Builders to understand what they are and why they are required. SAP in fact plays a very important role in the design and construction of a new build property. 

Standard Assessment Procedure (SAP) 

SAP is the government approved calculation method used for the assessment of energy performance in new build homes.

It is required for Building Regulation/Standard compliance both before a property is built (Design Stage) and after (As-Built). Lack of a completed SAP Report or a report that fails to meet the compliance targets, will potentially obstruct the building development.

A SAP Energy Performance Certificate (EPC) is also produced, which provides a SAP rating displayed on a scale between 1 and 100+. A higher SAP rating represents a property with lower estimated fuel costs and carbon dioxide (CO2) emissions.


When do I need a SAP Calculation?

Once you have secured your plot and designed your home, you will need to have your building control/warrant application approved by a Building Control Officer (England, Wales, NI) or Verifier (Scotland) in order to commence construction of your project.

Certain requirements must be met in order for your application to be approved. Energy Efficiency is one such requirement which is achieved through the provision of SAP Calculations. 

Design Stage- Before you begin construction

Self BuildersA SAP assessor/ On Construction Domestic Energy Assessor (OCDEA) can provide calculations based on accurate and scaled drawings including any elevations, sections, floor plans and site plans.

The SAP Calculation will provide a Target Emission Rate (TER) and Target Fabric Energy Efficiency (TFEE) based on a standard (notional) dwelling which is the same shape and size. A proposed Dwelling Emission Rate (DER) and Dwelling Fabric Energy Efficiency (DFEE) is also calculated in order to demonstrate that the designed property does not exceed the target rates. 

You can find out more about Design Stage SAP Calculations here


As-Built Stage- After construction

NewBuildhouseOnce your property has been constructed, a final EPC is required alongside an As-Built SAP Calculation. This calculation will determine whether your self build (now constructed) still meets the requirements set by Building Regulations/Standards. 

An Air Tightness test is also completed at this stage to ensure that the property has been constructed to a good level, where the air/heat will not leak through the building fabric.

Any changes made to the property may impact the Dwelling Emission Rate (DER) and Dwelling Fabric Energy Efficiency (DFEE). If these exceed the target rates established at Design Stage, then the SAP Report will Fail and an EPC cannot be issued. It is illegal to put the property up for sale or let without a valid EPC.

You can find out more about As Built SAP Calculations here

Do I require SAP Calculations for other Building Projects?

If you are undertaking a renovation project or plan to build an extension then you may still require a SAP Calculation to ensure your project is compliant with regulations/standards. More information can be found on the pages linked below:

SAP Calculations for Extensions >  SAP Calculations for Conversions >

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