Part L - SAP Calculations & SAP EPCs

SAP Calculations carried out Nationwide

If you need a SAP Calculations or a SAP Energy Performance Certificate, call us anytime.  SAP Calculations can only be issued by trained and qualified assessors.

We pride ourselves on our customer service, we believe it is important to be polite, considerate and on time when we enter a customer’s property.  You can rely on us to have your SAP Calculations ready quickly when you need it.

What are SAP Calculations and SAP EPCs?

SAP stands for ‘Standard Assessment Procedure’ and is the government’s method for calculating the energy performance of dwellings.

These calculations are only necessary for residential properties. SAP calculations measure two elements; the Dwelling Emission Rate (DER) and Dwelling Fabric Energy Efficiency (DFEE).

The calculations determine a Target Emissions Rate (TER) and a Target Fabric Energy Efficiency (TFEE) rate. The DER and DFEE must be lower than the TER and TFEE.

SAP calculations come in two formats; L1A (new builds) and L1B (extensions and conversions).  These should be completed prior to any works being carried out (the design stage) and then finalised when the property is completed (the as built stage).

How quickly can I have my SAP Calculations & SAP EPC?

It depends on the size of your property however, on average it takes about 3 days to complete.  We will require a full set of plans and  building details to start the process.


I have been using Assessment Hive for quite some time now. I find them very friendly, efficient and would definitely recommend their services to others”.
Savvas Eracleous, E & M Solicitors


“Amazing professional service everytime! extremely friendly and helpful staff, reports are done fast and to a high standard. Here at Platinum Estates, we highly recommend this company.”
Lory Godfrey, Platinum Estates


“Amazing service each and every time we instruct! extremely friendly and helpful staff.  I had SAP Calculations that needed to be done urgently. These were carried out the next day and certificates issued that day, Thanks so much”
Mehmet Bekir, Builder/Developer

4 simple steps when ordering from us

Get a Quote

Call us or get a free quote online. We are happy to answer any questions you have.

Book It

Once you let us know what you need your case will be assigned to one of our fully trained assessors.

Assess It

If an appointment is needed, your assessor will meet with you or any third party at the property.

Report It

When the assessments have been completed, we will send you the completed reports by email or post.

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SAP Calculations and SAP EPCs Explained

More about SAP Calculations and SAP Energy Performance Certificates

SAP Calculations is the Governments method for calculating the predicted energy efficiency of residential buildings.

SAP Calcs come in two formats.  Firstly, L1A SAP Calculations for new builds and secondly, L1B SAP Calculations for extensions and conversions. The primary purpose of the calculations is to produce a SAP Energy Performance Certificate.  These are also known as SAP EPC, SAP energy performance certificate and New Build EPC.

In addition, do feel free to view our blog page or our more recent SAP Calcs blog.

sap calculations

New Build Properties

In this paragraph, we explain how the SAP Calculations for New Builds are carried out.

In all cases apart from extensions that we will cover later in this article there are 2 steps.

Firstly, the Design Stage.  At this stage, we will work up preliminary SAP Calcs to see if compliance is met.

Two elements are met, the Dwelling Emission Rate (DER) and Dwelling Fabric Energy Efficiency (DFEE).

The calculations determine a Target Emissions Rate (TER) and a Target Fabric Energy Efficiency (TFEE) rate. The DER and DFEE must be lower than the TER and TFEE.

If the dwelling fails however, we will work with you to find a solution.  The solutions will take into account practically and budget

Secondly, the As Built Stage.  This stage will take place once a dwelling nears completion and air test has been carried out.  At this stage, we will use the final information and produce the SAP Energy Performance Certificate.  This is also known as EPC SAP, SAP and EPC, new build EPC, EPC for new build or SAP EPC.

It’s important that both stages take place to ensure that compliance is met and to avoid any nasty surprises that may arise later.

Above all, the relevant documents will be provided to you at all stages to ensure sign off.

In addition to this page, please feel free to view our New Builds blog.

SAP Calculations for existing properties

If you are converting a property from 1 unit to 2 or more you will also require SAP Calculations for conversions.  Local authorities may also refer to these as Part L1B SAP calculations.

Unlike the new build calculations, conversion calculations in SAP do not require DER and TER.

To ensure compliance is met for conversions, we produce U-Values within our software. This is to check if the properties meet the requirements provided in the approved documents. If these values are too high or do not meet the standards, we will work with you to meet compliance.

We will provide all the documents for you to submit to planning and building control. Once the properties are completed, we will also issue the SAP Energy Performance Certificates.

Are you extending your property?

SAP calculations for extensions are also known as Heat loss calculations for over-glazed extensions.

Part L1B of the Building Regulations presents a flexible approach for extensions. In these circumstances, you would need to compare two reports. The Notional Report (minimum standards) and The Proposed Report (actual standards).

Firstly we produce a Notional Report, the minimum standards.  Secondly we produce a Proposed Report, the actual standards.

This should prove that the CO2 from the house and extension (the Proposed Report) is no higher than the house and extension in the Notional Report.

In addition to this page, please feel free to check our Extensions Post.

What is the process and how do I instruct you?

The process is fairly straight forward.

Firstly, we will email you our quotation together with scope of works and insurance schedule.  .

Usually projects have a set of plans and specifications.

We will insert the information from the documents into our software, to produce the reports.

We will then send you the final reports with any recommendations.

Buildings that fail, no problem.

If your building fails however, we will look to work with you to achieve a pass offering practical solutions.  This Technical Consultancy is included within our fees and distinguishes us from many of our competitors.

In addition to this webpage, please feel free to view our eBooks Page for free eBook download.

Once the Calculations are complete, we will provide you with the relevant reports  This will show compliance has been met and the energy performance of the property.