What is a SAP Calculation?

SAP stands for Standard Assessment Procedure.

A SAP Calculation is required by Building Regulations and is the only Legal Government System in the UK that evaluates the energy rating for a property. A Standard Assessment Procedure of a home's energy efficiency (SAP) is based on a calculation that ranges from 1 to 100.

A score of over 100 would indicate that the house is a net energy exporter and has zero energy cost. A score of 1-10 means that the property is extremely inefficient and needs improvements.

The SAP calculations are based on the estimated energy costs and fuel costs of a property.

They take into account various factors such as;

  • The building and its construction.
  • The heating and hot water system.
  • The internal lighting of the property.
  • The use of renewable technologies and energy sources.

According to the Building Regulations, a SAP Calculation and a Predicted Energy Performance Certificate are required for new dwellings prior to the commencement of work. The two main formats of SAP calculations are L1A (new buildings) and L1B (extensions & conversions). The purpose of these is to produce an updated or new Energy Performance Certificate.

Note: These calculations are only necessary for residential properties.


When do I need a Standard Assessment Procedure/SAP?

SAPs are required during the design stage, when building control will require a valid SAP calculation to be submitted with a building regulations application.

Along with the SAP Calculation, MyConstructor can provide you the following, after request:

  • Advice & Guidance by our professionals on your design and compliance.
  • Improvement recommendations that can be made on the property.
  • In the long-run, and after the build is finished, we can finalise your SAP calculations and create your valid Energy Performance Certificate/EPC.

The stages of a SAP Calculation

SAP Calculations usually involve four basic stages that are as follows:


Design - Draft Stage

The information collected by the designer and given to the assessor for the SAP calculations, is used for creating a summary of the building's total floor area. This includes the various areas of the house that are affected by heat loss, such as the floor area of the living room and the heat loss walls.

The assessor then uses the data collected by the designer for the SAP calculation, to determine the building's thermal elements. These are expressed as U values and their purpose is to describe the rate at which heat moves through the building's fabric. Higher values indicate that the building loses more heat.

The information is related to:

  • The type of the building.
  • Floors.
  • Roofs.
  • Walls.
  • Openings (doors, windows etc.).
  • Main & Secondary space heating.
  • How water is generated.
  • Renewable technologies.
  • Energy efficient internal lighting.

The software used by the assessor determines if the proposed dwelling will meet the Building Regulations' Requirements, regarding the conservation of power and fuel.

It then allows the designer to modify the building's design to meet the requirements, if needed. The assessor can then use the software to model variations of the design to identify areas where the building can improve its efficiency.


Design - Final Stage

In this stage, the finalised version of the design is agreed by the assessor, the client and the designer. Then, the final design is submitted to the computer program for approval. This process can involve amendments to the design to meet the requirements of the Building Regulations.

The assessor then compiles reports about the building's design and the client submits them to the Building Control. This process can also involve the creation of a Predicted Energy Assessment, which shows the building's energy performance based on the design.


Built - Draft Stage

Most new dwellings will typically require an Air Pressure Test to determine if the building's air leakage is below 15 meters. The designer or client can then provide the results of the test and advise of any variations, if needed.

After reviewing the air pressure test results, the SAP calculation is updated to reflect the changes made to the specification. The updated version of the calculation is then used to check that the building still complies with the Building Regulations.

The building's address should be registered on the national database of property addresses maintained by the government. If it's not, the address record must be arranged.


Built - Final Stage

In this stage, the assessor then uses the SAP calculation to create an Energy Performance Certificate, or EPC for short. This report provides a rating of the property's energy efficiency based on the building’s built condition. The EPC certificate must, by UK law, be displayed in a new home that’s for sale on the open UK market.

Aside from the Energy Performance Certificate, other documents that the Building Control requires;

  • SAP worksheet report.
  • SAP data input report.

After that, the client receives the reference of the Energy Performance Certificate so that they can easily obtain a copy. The Energy Performance Certificate can be found on the government’s website for public buildings, homes, and businesses in England.

Note: Building Regulations require that an Energy Performance Certificate must be provided before a completion certificate can be issued.


What is the cost of a SAP Calculation?

There are no fixed rates for Standard Assessment Procedure Calculations. The final cost may vary depending on a different number of factors such as;

  • Is the building new or just extended?
  • What is the Energy Performance Certificate/EPC price? Prices start from £34 through MyConstructor.
  • Are there any improvements required?

Who can issue a SAP Calculation and an EPC?

SAP calculations are made by authorised and registered SAP Assessors with a certification authority. On the other hand, an EPC must be conducted by a icened Energy Assessor. In any other case, both SAP and EPC are not valid.


How long will the SAP Calculation take?

The time of the procedure is not standard and depends on the timeline of your construction project. The bigger the project, the more time is needed for the procedure to be done. Generally, UKBC aims that all the reports are completed, after request, within 5-10 working days.


How can I book my SAP Calculation online?

The process of getting an SAP, and applying also for EPCs, is incredibly simple with the help of MyConstructor.co.uk. Through our website, you can easily book a SAP Calculation and compare prices and reviews of professionals all across the UK. One of the most exciting features of our platform is that it allows you to get instant prices!


Don’t Think Twice! Hire A Professional Today

Getting ready for your construction project can be a stressful time. Before you start the process, it's important that you plan ahead and hire the help of a professional SAP Calculation Assessor.

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