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Building regulations are constantly changing and none more so than those related to energy efficiency requirements. 2020 will see a whole raft of new legislation including changes to Part L & SAP 10.

As a consequence, we are delighted to have launched our new online Knowledge Centre which offers developers key information on all updates to energy efficiency regulations. This is proving an invaluable and informative tool for all those planning a new development. In addition, we now offer Standard Assessment Procedure (SAP) calculations designed to give accurate information for developers to assess the energy efficiency rating of new dwelling, conversions, renovations and extensions.

Implications for the Update to Building Regulations

For clients starting new developments early next year, all changes to Part L will need to be incorporated into the development plan.

This will have implications for assessors who will have to learn how to use new software. However, change to these documents aren’t always a bad thing.

Quite often, changes to building regulations (BR) are simply to refine the documents and make them clearer. Although, inevitably they do bring new criteria which must be understood and planned for if developers are achieve compliance in the respective BRs. We will break down some of the key changes to energy efficiency and highlight how this will affect developments moving forward.
It’s clear that more energy efficiency regulations increase the demand on developers to plan their projects using correct information. Navigating a project through numerous regulatory frameworks can be complex and time consuming – no more so than in reference to energy efficiency and SAP calculations.

What are SAP Assessments and How We Can Help

Standard Assessment Procedure (SAP) is the official methodology used by the Government to assess the energy efficiency rating of a new dwelling as well as conversions, renovations and extensions.

This is a mandatory requirement of Building Regulations Part L1A (new build) and Part L1B (existing) and without it, you will not be granted building sign off.

We offer a comprehensive SAP calculation that will allow you to meet full compliance with all regulatory demands. Our team of highly experienced assessors will work with you to provide all pertinent information as well as practical solutions to ensure that your development meets all the necessary BRs.

All of our assessors are OCDEA accredited and can also issue EPCs.

Most importantly, our SAP calculations will allow us to provide energy efficiency ratings for properties under Building Regulations Part L1B for conversions, renovations and extensions – offering accurate information for you to use when planning your project. We list a few examples of how SAP assessment will impact on construction projects.

SAP Assessments and Changes in fuel and CO2 factors

In the past it has been difficult to pass a SAP assessment with electric heating (eg. panel heaters/electric boiler) due to its high carbon factor. SAP 10 will remove some of this burden. It plans to reduce the carbon factor of electricity from 0.519 kgCO2/kWh to 0.233 kgCO2/kWh, essentially making it easier to pass the SAP assessment with electric heating, good news! The Bad news is that Solar PV will have less of a positive impact on the SAP results, meaning more PV will be needed to meet local planning requirements on certain developments.

SAP 10 and Overheating Risk

Designers will be encouraged to reduce heat gains in areas other than ventilation through openable windows. SAP 10 has reduced the amount of ventilation that designers can assume is being gained from open windows and will thus impact on the choices available to developers. Our team of certified assessors will be able to offer advice on the best courses of action for your particular project.

Thermal Bridging

Accredited Construction Details (ACD) is being removed and replaced with more precise thermal bridging data recording and calculations. There is little information on this so far, however we hope it will give designers a better understanding of how this affects heat loss in a dwelling.

Detailed Calculation of Thermal Mass Parameters

A key update to the Part L regulations is that developers will no longer be allowed to select a low, medium or high thermal mass as rudimental thermal mass parameter. They will need to be calculated based on build material, construction and kappa values. Again, the team here at Base Energy will be able to offer you the solutions that will allow you to plan and complete you project in full compliance of the new BRs.

Greater accuracy for Solar PV Impact

Different CO2 reduction targets should be included with all new calculations. The new formula will only factor in a PV supply to those flats directly connected.

Water Usage

A more precise estimate of water usage will be applied to the SAP calculation, inputting flow rates and fitting types.

In Summary

The new standards seek to make the planning and design calculations more accurate across the board. There is no confirmed deadline for release of the new software however, the consensus is that we can expect it in early 2020.

Both BRE and BEIS have released documentation and demo software to help you understand the changes SAP 10 is bringing and how prepare for any new technical aspects. Until SAP 10 comes into force (and once Part L Section 6 is updated), continue to use SAP 2012 for Building Regulations compliance and EPCs.

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