What is a Good SAP Rating?

If you’re in the process of buying a new build property or are having a conversion or extension built, you may have come across the term SAP Calculations, SAP Scores, or SAP Rating.  SAP calculations simply work out the efficiency of a property, informing the wider known EPC rating. 

But what is a good SAP rating? The higher the SAP score is, the better the rating. A score of 100, for example, indicates that a property is so energy efficient that it has zero energy costs, and anything over 100 indicates that a property is actually exporting energy. The top EPC rating A would equate to an SAP score of around 92-100. 

To learn more about good SAP ratings and how they are achieved, keep reading. 

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What is a Good SAP Rating?

A good SAP score is a high SAP score. Anything in the region of 69-100 is considered to be a good score, but SAP calculations between 92-100 are the gold standard, equating to an EPC rating of A. This means that a property consumes less energy, and has a lower impact on the environment which, in turn, creates lower energy bills. 

SAP calculations inform the more widely known EPC ratings. This simply indicates how energy efficient a property is. You can see from the table below that an SAP rating of 69-100 is considered good, whereas scores below this indicate that a property requires work to make it more energy-efficient. By 2035, the aim is for all domestic properties to have a minimum rating of 69-80.

SAP ScoreEPC Rating
92-100A
81-91B
69-80C
55-68D
39-54E
21-38F
1-20G

What is the Highest SAP Rating?

The highest SAP rating is 100, equating to an EPC rating of A, however SAP ratings can exceed 100 where a property creates energy. For example, a property that is completely self-sufficient energy-wise would have a rating of 100, but if it creates energy in excess of what is required to supply the property, perhaps with the use of solar or wind power based on the property, the SAP score would exceed 100 in proportion to how much excess energy it creates. 

How are SAP Ratings Calculated?

SAP ratings are calculated based on how a property uses and loses energy across various categories, which are given a score. This information is then collated, and considered together to determine the overall SAP Rating. This is then used to help inform the EPC rating. Areas of the property that are evaluated to calculate the SAP rating include:

  • The materials used
  • The efficiency of heating systems
  • The level of thermal insulation used
  • The use of renewable energy
  • The fuel used for water, space heating, light, and ventilation
  • Air leakage and solar gains found through openings in the property
  •  C02 emissions
New Build House

How Do I Pass an SAP Assessment?

In order to pass an SAP assessment, the above considerations must be taken into account, demonstrating construction quality and low energy costs. 

A new build needs to show that the Dwelling Emission Rate (DER) and Dwelling Fabric Energy Efficiency (DFEE) is lower than the notional TER (Target Emission Rate) and TFEE (Target Fabric Energy Efficiency) in order to pass the assessment.

New build properties should take this into account during the design stage, but when working on a conversion, it needs to meet L1b regulations of which the below advice should help:

  • Double Glazing – Upgrading windows and doors can improve both energy performance and can reduce noise pollution.
  • Loft Insulation – This is easy to install, is inexpensive, and can greatly impact your SAP score. 
  • Wall Insulation – Insulating walls can improve your SAP calculation, and you may qualify for help with the cost.
  • Boiler Replacement – A new energy-efficient boiler can greatly reduce energy costs and improve your SAP score.
  • Floor Insulation – Floor insulation will help to minimise heat loss and can help to reduce heating bills. 
  • Secondary Heating Source – A secondary heating source, such as a wood-burning fire, can reduce energy costs and improve energy efficiency. 

Your current EPC rating certificate should also contain information relating specifically to your property with advice on how the EPC rating can be improved. 

It is the aim of the UK government that by 2035, all domestic properties should have an EPC rating of C or above (SAP Rating of 69-100). Undertaking some of the above tasks now may help to improve your EPC rating in time to achieve a score of C or above before this time. 

Extensions are assessed differently as we are only looking at the carbon emissions for an extension with 25% glazing, and the proposed extension, so a SAP/EPC rating is not given.

Is SAP the Same as EPC?

An SAP rating is not the same as an EPC rating, but SAP calculations inform the EPC rating. SAP calculations work out the energy efficiency and potential energy costs of a property, which is then used to work out the EPC rating – the publicly available, easy-to-read proof of the SAP calculations. 

Generally speaking, individuals do not have access to SAP calculations but do have access to EPC ratings. The EPC rating will not contain all of the SAP calculations and the details that went into those calculations but will contain information about how the energy efficiency rating can be improved with advice relating to the property in question. 

Learn more about the difference between SAP calculations and EPC ratings in our recent blog here

SAP Calculations for New Builds, Extensions, and Conversions

RS energy are SAP calculation and energy compliance experts. We provide SAP calculations for a wide range of clients on new build properties, conversions, and extensions. As accredited SAP assessors, we’re here to support you through the process of making your property more energy-efficient, both in the design and build phases. 

Get in touch with us today to learn more about our SAP calculation service.