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What Exactly Are SAP Calculations?

So, what exactly are SAP calculations? SAP is the abbreviation for “Standard Assessment Procedure” and is the method used by the government to calculate the energy efficiency of houses.

These calculations are only required for residential homes. In England the SAP calculations are based on two components that are The Dwelling Emission Ratio (DER) as well as the Dwelling Fabric Energy Efficiency (DFEE).

The calculations establish the TEAR (TER) and the targeted Fabric Energy Efficiency (TFEE) rate. It is important to note that the DER and DFEE should be lower than the TER and TFEE. The report only covers Wales and Scotland the report is only measuring the DER however building regulations standards are higher.

SAP calculations are available in two formats: L1A (new constructions) and then L1B (extensions as well as conversions). The primary goal of the calculations is to generate an updated or new Energy Performance Certificate (EPC).

What is the reason I need SAP Calculations?

Calculations are required under Part L (England and Wales) as well as Part L (England & Wales), Section 6 (Scotland) as well as Section 6 (Scotland), and Part F1 (Northern Ireland) of the building regulations standards. These regulations concern the preservation of power and fuel. Since their first introduction back in 1995, these rules were amended numerous times to reflect the effectiveness and availability of modern technology. It is necessary to conduct these calculations to create a new or current Energy Performance Certificate (EPC). An EPC is legally required to rent or purchase a residence house. The EPC scores the property from an A (worst quality) up to the A (best) on two aspects that are energy efficiency and the environmental impact score. As of April 1, 2018it became illegal under the law to lease any property that has either an F or G score in any of the categories.

How Do SAP Calculations Completed?

For our team to perform calculations, customers must give as much detail as they can.

This can include but isn’t included in:
Site Plan
Type of insulation and thickness
U-values of openings
Heating systems: Specification
Hot water generation
Percentage of lighting with low energy
Specification of the ventilation system
Renewable technologies
Accredited construction details

The way your SAP calculations are conducted depends on whether the project is a brand new build or an expansion or conversion. If so the calculations are separated by two reports: the L1A SAP and L1B SAP

L1A SAP Calculations Information

When you build a new building For new builds, you SAP computations will be broken down by two report: the ‘design phase as built’ and ‘design stage’.

Did You Know? You can find out more about SAP calculation extension on the website.

Design Stage Report

Before construction starts the team from our office will review and approve the construction specifications for the building.
This information is entered into calculation software to calculate TER as well as TFEE rates as well as to show that the structure can be deemed to be DER and DFEE conforming.
A “predicted energy assessment” is created.

As Built Report

After the building has been completed after which the building’s details are assessed again and any final information is added like boiler model and air tightness scores.
The final report was the EPC.

L1B SAP Calculations Information

L1B SAP calculations for conversions and extensions are split into ‘notional’ and “proposed’.

Notional Report
Our team will analyze the construction aspects of the entire property and the extensions or the conversion. Then, they’ll produce a report using benchmarked information.
In order to create the report the construction details are fed into SAP calculations software to create theoretical TER and TFEE rates as well as DER and DFEE measurement.

Proposed Report
The report proposed will utilize the benchmarked data of elements that are already in use. For new or upgraded elements our team will analyze the actual performance information.
The information is then fed into SAP calculation software to calculate the suggested TER and TFEE rates as well as DER and DFEE measurement.
The performance levels of the proposed elements have to be less than benchmarked standards to allow the property to be considered to be acceptable.
Furthermore to this, the total DER and DFEE measures should be less in the report proposed as compared to the report that was notional.
When the property’s SAP calculations show how the property’s efficiency figures are lower in the report proposed than in the actual report the new EPC is prepared, replacing the existing EPC.

What is the best time to have an SAP Calculation Be Explicitly Applied?

It is essential to carry out SAP calculations prior to when construction work gets underway. At the designing stage, you will be sure that the drawings and specifications will satisfactory result. For A SAP L1A calculations a subsequent report is required to be prepared once the construction is complete.

How Long Will the SAP Calculation Be?

It is entirely dependent on the timing that your building project. In general, UKBC will complete every report within five to ten days following the your request.

What happens if my Building Doesn’t Work?

It is illegal to lease or sell the property without having an EPC. This is why it is essential that your building has passed its SAP. It is essential to plan your SAP calculations prior to the time that construction work begins, in order in the event that the building is not in compliance with building regulations standards the SAP assessors will be able to provide you with tips on how you can improve. This can be more challenging and costly later on during the construction phase, as the range of modifications offered is less. UKBC strives to provide complete support and assistance throughout the SAP process. While many companies only perform their calculations UKBC offer our customers a consulting service to ensure that our clients have the right information and assistance they need to be successful in the SAP.