Part L: SAP Calculations

Building Compliance Testing Limited can provide you with a fast and cost effective Elmhurst Certified SAP Calculations.

green tick BCTSAP Calculations

SAP stands for ‘Standard Assessment Procedure’. A SAP assessment involves using a calculation method to predict the energy performance of a building – this includes houses, flats and all other residential properties. However, it is not just required to have a SAP calculation carried out on a complete new build, it is also a requirement for certain extensions which exceed the threshold and any conversions.

This calculation works by assessing the level of energy which is likely to be used, taking into account the expected occupancy, and based on an average, comfortable way of living.

The calculation is a desk based assessment and is typically split into two parts:

The first part is the design stage. At this stage, the assessor will work up a preliminary SAP assessment based upon the proposed/assumed design and specification to see if compliance is met. If the dwelling is falling short of compliance, we work with our clients to find a solution which meets their requirements in terms or practically and budget. This is known as Predicted Energy Assessment (PEA).

SAP takes into consideration:

– Building materials

– Insulation values

– Thermal Bridging


Air Tightness

– Heating and lighting

– Renewable energy technology 

To learn more about what are SAP Calculations click here.


When Is A SAP Calculation Required

New-build SAP Calculation

Extension SAP Calculation

Conversion SAP Calculation

Over-glazed SAP Calculation

The SAP Calculation Process


A SAP Assessor commences their work by utilizing architectural plans and construction specifications in conjunction with a comprehensive HVAC (heating, ventilation, and air conditioning) specification. Consequently, the drawings must be meticulously scaled, accurate, and encompass all facets, including elevations, sections, floor plans, and site layouts.

The assessor then proceeds to create a model of the dwelling(s) within SAP software, working from these scaled plans, whether manually or electronically. This digital representation forms the foundation for SAP Calculations.

Within this model, the assessor integrates the heating, lighting, and ventilation systems, selecting specific products from manufacturer databases when applicable. Detailed thermal elements, encompassing walls, floors, roofs, and openings, are meticulously included, along with calculations for thermal junctions. Additionally, any renewable technologies and cooling systems are incorporated.

Upon finalization, the SAP calculation generates an array of comprehensive reports, spanning site layout, heat losses, energy demands, seasonal variations, CO2 emissions, renewables contributions, and numerous other aspects.


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Other Services

We can also offer a variety of other specialist services through our Partners, including:

Water Efficiency Calculations

Air Permeability Testing

Overheating Assessments

– U-value Modelling

– SBEM Calculations

-Energy Statements

Frequently Asked Questions

How do I prepare for a SAP Calculation?
  • In order for us to create your SAP and EPC, we will require the following:
    The architect’s building regulation drawings (floor plans, cross sections, elevations, site plan)
  • Construction specification details (such as a wall, floor, and roof build ups, heating systems, any
    renewable technologies installed)
  • Window specification
  • Any renewable systems being utilised
We’re friendly and knowledgeable bunch so why not get in touch for a chat. You can always contact Building Compliance Testing with any questions through phone, email or our online chat service.

Don’t worry, we don’t charge for advice given over the phone, so why not ask for a free quote?

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