Do I Need a SAP Calculation for a New Build?

If you’re building a new build home, you might have come across the term SAP Assessment or SAP Calculation. But, does this apply to you? Do you need a SAP calculation for a new build? In this article, we take you through any SAP assessment and other assessments required for new build homes. 

So, do you need a SAP calculation for a new build home? Yes, all new build dwellings require a SAP calculation and a predicted EPC rating to be submitted for review prior to building commencing. A final EPC rating must also be submitted once the home is complete. 

Read on to learn more about SAP calculations for new builds.

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Do I Need a SAP Calculation for a New Build House?

SAP Calculations and EPC ratings are required for new build homes. Many firms will assess the property at the design stage, before building commences in order to provide advice on how to save energy, and will then guide you through the process of EPC ratings and lodgings once the house is built. 

To assess the SAP rating of a new build house, the following steps will be conducted:

  • Calculation of heat loss, considering conduction and convection heat losses
  • Determination of the amount of heat required to maintain the property at a comfortable temperature
  • Determination of the amount of energy required to provide hot water and lighting
  • Calculation of the amount of energy required to provide the heat, hot water, and lighting, considering the efficiency of the boiler and other building services
  • Calculation of the cost of energy based on standard fuel costs
  • Calculation of carbon dioxide emissions based on standard emission rates.

What’s the Difference Between SAP and EPC?

Standard Assessment Procedure (SAP) calculations are the methodology behind EPC ratings. SAP considers both the Dwelling Emission Rate (DER) and Dwelling Fabric Energy Efficiency (DFEE), as well as a variety of other factors, before being used to inform the EPC rating of a building.

EPC Ratings are the publicly available certificates that detail the energy efficiency of a home, with rankings from A-G. Rankings at the top end of the scale (A – C) are considered good and reasonably energy efficient, whereas anything below E is generally considered bad. For reference, rental properties must be rated E or above by law. 

Learn more about SAP and EPC ratings in our recent blog post here

new build house

What EPC Rating Should a New Build Be?

There is no minimum requirement for new build EPC ratings, although SAP ratings must be submitted, alongside a predicted EPC rating before building commences. 

That being said, most new build homes have a good EPC rating; 70% of new build homes have an EPC rating of A or B. In comparison, just 12% of existing homes have an EPC rating of A or B.

Are Predicted Energy Assessments Still Required?

Predicted energy assessments (PEA) are required alongside the SAP calculation that is submitted prior to building commencing. A PEA must have been submitted before an unbuilt dwelling is sold. 

PEAs provide information about the predicted energy efficiency of a building, comprising the SAP and Environmental Impact ratings. They can only be conducted by On Construction Domestic Energy Assessors (OCDEA’s) who are accredited by a Government approved scheme.

Once the building is complete, the final energy performance of the property must achieve at least the predicted energy consumption detailed in the PEA to receive its final sign-off from the building inspector.

How Long Do SAP Calculations Take?

How long SAP calculations take depends on the timeline of the project. However, many companies will aim to complete reports within 7-14 working days. We recommend that you book your assessment in good time so that any periods of waiting will not set back your project timeline.

kitchen of a new build house

SAP Calculations with RS Energy

RS Energy provides a fully supported SAP Calculations service for Architects, Developers, and Builders in England and across the UK. As accredited On Construction Domestic Energy Assessors (OCDEA), we’ll efficiently take care of your SAP calculations from design to build and EPC lodging. 
We work on new build domestic dwellings, conversions, and extensions, as well as providing energy statements, and water calculations. Get in touch with us today to learn more.

Do I Need a SAP Calculation for an Extension?

Extensions require SAP calculations as many now exceed the 25% glazing in relation to the new floor area allowance stipulated in the L1B Building Regulations. Without submitting a SAP calculation, your extension will not be compliant. 

Like with new builds, the SAP assessment should be submitted prior to work commencing.

Do I Need a SAP Calculation for a Conversion?

SAP calculations are required for all residential conversions to ensure that the conversion complies with the L1B Building Regulations. This is particularly important if you are changing the intended use of the original room/building/area as the energy performance may be affected for good or bad with building work. 

Again, the SAP calculation should be submitted before any work commences on the conversion.