Ene 01 - Reduction of energy use and carbon emissions

BREEAM New Construction UK 2018 – Post-Occupancy Stage assessment - KBCN1532

Following the publication of UK NC V6 it was announced that the Post-Occupancy Stage (POS) assessment within BREEAM will close with immediate effect. While we will no longer be offering this as an assessment option, the essence and intent behind the criteria will remain. At this stage, we will not be re-issuing the UKNC 2018 manual. Therefore, reference to POS will remain within the following issues:

Ene 01 Reduction of energy use and carbon emissions (two credits for Post-Occupancy Stage)
Ene 02 Energy monitoring
Wat 01 Water consumption
Wat 02 Water monitoring

To award the relevant credits, the references to ‘Post-Occupancy Stage assessment’ should be read as ‘Post-Occupancy Evaluation’ and carried out with the same intent; to understand and close the performance gap. For assessments that have been certified at Post-Construction, are in progress or are new assessments, the Post Occupancy Evaluation process should continue to be followed, however there is no formal post-occupancy BREEAM certification stage. Rating systems such as BREEAM in-Use and NABERS UK Energy for Offices are examples of tools that can be used to measure performance in the operational phase.

18-05-23: KBCN edited to illustrate that credits can be awarded.

Calculating EPR where there are multiple BRUKL/NCM outputs - KBCN1083

Where more than one NCM output is produced for a development, which is registered as a single assessment, an area-weighted average should be used to calculate the number of credits to be awarded. This does not apply where the ‘similar buildings’ approach is used. For for projects in England assessed under UKNC V6.0, please see KBCN1618 Projects assessed under UKNC V6.1 can upload multiple BRUKL.inp files for a single assessment and the platform will perform the calculation. See KBCN1618 Each energy performance output from the NCM output (actual CO₂/m² notional CO₂/m² etc.) must be area-weighted to produce area-weighted average values entered into the scoring and reporting tool. When applying this method, please include your area-weighting calculations and outputs as supporting evidence. The following provides an example of an area-weighting calculation for two building areas A and B, each of 500m², for which separate NCM outputs are available: For building area A: Notional building heating and cooling energy demand: 230 mJ/m² Actual building heating and cooling energy demand: 200 mJ/m² Notional building primary energy consumption: 300 kWh/m² Actual building primary energy consumption: 280 kWh/m² TER: 40 kg CO₂-eq/m² BER: 30 kg CO₂-eq/m² For building area B: Notional building heating and cooling energy demand: 150 mJ/m² Actual building heating and cooling energy demand: 140 mJ/m² Notional building primary energy consumption: 200 kWh/m² Actual building primary energy consumption: 190 kWh/m² TER: 40 kg CO₂-eq/m² BER: 38 kg CO₂-eq/m² Area-weighted values for building areas A and B (of total floor area 1000m²): Notional building heating and cooling energy demand: 230*500/1000 + 150*500/1000 = 190 mJ/m² Actual building heating and cooling energy demand: 200*500/1000 + 140*500/1000 = 170 mJ/m² Notional building primary energy consumption: 300*500/1000 + 200*500/1000 = 250 kWh/m² Actual building primary energy consumption: 280*500/1000 + 190*500/1000 = 235 kWh/m² TER: 40*500/1000 + 40*500/1000 = 40 kg CO₂-eq/m² BER: 30*500/1000 + 38*500/1000 = 34 kg CO₂-eq/m² These area-weighted values are then used to calculate the overall EPR_NC value.

20 Sep 2023 - Minor corrections, applicability to INC V6 confirmed and cross-reference to UKNC V6 guidance added.
14 Jun 2023 - Note added to confirm this is integrated into the platform for UKNC V6.1 in all countries. 
24 Aug 2022 - Note added to confirm this is N/A to UKNC V6 for projects in England
07 Feb 2022 - Reference to 'BRUKL' amended to 'NCM output' to clarify for non-UK assessments
31 Oct 2018 KBCN clarified. Reference to EPRs and calculation example added

Definition of Accredited Energy Assessor - KBCN0706

BREEAM recognise that CIBSE Low Carbon Design and Simulation consultants are qualified to confirm compliance with Part L Building Regulations and are therefore qualified to produce BRUKL reports demonstrating compliance with Ene 01.

Technical manual to be updated accordingly in next re-issue.

Energy consumption and carbon emissions of untreated spaces - KBCN00049

Where the assessment contains a mix of treated and untreated spaces, untreated spaces can be excluded and the performance based on the treated spaces only. Where the entire assessment is untreated, the whole of the structure(s) must be assessed on the basis that this issue is critical for certification. BREEAM is primarily designed to assess permanent, treated and occupied structures. Untreated structures are unlikely to gain many credits when being assessed.

24/08/2022 - Applicability to UKNC V6 confirmed

Energy modelling not required for Building Regulations compliance - KBCN0487

For the purposes of demonstrating BREEAM compliance, it is still necessary to undertake energy modelling to generate the required performance data.

24/08/2022 Applicability to UKNC V6 confirmed

Energy performance assessment for part of a whole building - KBCN0596

If the assessment is only covering part of a whole building, the energy performance assessment must be representative of the part of the building being assessed. Simply taking the energy performance assessment of the whole building would not therefore comply, especially if the non-assessed parts of the building were of a different use. A separate energy assessment of the part of the building is likely to be required. The energy performance assessment must be representative of the parts of the building being assessed. This also applies to the predicted energy performance and all energy modelling for the prediction of operation energy consumption.

24/08/2022 - Applicability to UKNC V6 confirmed
Amended 01/09/2020 to cover UKNC2018 - Prediction of operational energy consumption

Exemplary credits for Post-occupancy stage - KBCN1400

The 'Four credits - Prediction of operational energy consumption' need to be achieved before assessing the two exemplary credits for 'post-occupancy stage'. This is so that the post-occupancy stage commitments have a prediction to be compared to. SH 24/08/22 Not needed for UKNC V6

GN32 Energy prediction and post-occupancy evaluation – BREEAM UK New Construction 2018 - KBCN1096

Latest version: v2.0, October 2022 The purpose of Guidance Note 32 is to describe the methodology for energy performance prediction and subsequent post-occupancy evaluation in BREEAM UK New Construction 2018. The guidance note relates specifically to the criteria within Ene 01 for:

Prediction of operational energy consumption (4 credits)
Post-occupancy stage (2 exemplary credits)

Download Guidance Note 32 View all Guidance Notes (licensed assessors only)

31-Oct-2022 - Updated following the closure of separate post-occupancy stage assessment. See KBCN1532.

GN39 Ene 01 Calculation Methodology – BREEAM UK NC 2018, V6.0, and V6.1 - KBCN1098

Latest version: v3.0, June 2023 Guidance Note 39 describes the calculation methodology for the energy performance criteria (up to 9 credits) in Ene 01 for BREEAM UK New Construction 2018, Version 6.0, and Version 6.1. Download Guidance Note 39 View all Guidance Notes on BREEAM Projects (licensed assessors only)

14-Jun-2023 - Updated for release of UK NC V6.1

LZC technologies – energy centre or other LZCs connected at a later stage - KBCN0267

If a project specifies LZCs that have been proposed in the feasibility report which reduce emissions, and/or will be connected to a site-wide energy centre operational at a later stage of the phased development, after the Post Construction Stage review has been submitted, the Energy and Pollution issues can be assessed as follows: In a phased development where the primary heating system will be upgraded at a later stage than the building being assessed, a commitment to install the new heating source must be made in the General Contract Specification (as per the BREEAM requirements). BREEAM does not specify a particular time for phasing as it is difficult to set parameters, however as a rule building users should have to wait the least time possible before they can use the upgraded heating source. For the quality audit, two Energy model outputs/EPCs must be produced at the final stage - one with the actual interim system installed for building control, and one for the BREEAM assessment which can include the predicted energy from the proposed energy centre. Additionally, the legally binding general contract specification for the new heating source must be submitted with details of the timescales proposed for the completion of the second phase of work. Where this approach is to be followed BREEAM must be consulted in each case to ensure that the arrangements are sufficiently robust to award the credits. BREEAM seeks to recognise the environmental impacts of a building's energy use throughout its life, therefore temporary arrangements can be accommodated, provided there is robust evidence on future connection to the permanent systems.

24/08/2022 - Applicability to UKNC V6 confirmed

Manual errata – up to V6 – prediction of operational energy consumption and minimum standards - KBCN1602

The technical manual refers to ‘4 credits for prediction of operational energy consumption’ as one of the requirements for achieving either Excellent or Outstanding minimum standards. This reference to 4 credits is incorrect, and will be removed in a future update. This is to make it clear that the requirement for Simple Buildings is for achieving the 'Prediction of operational energy consumption' criteria, not achieving four credits.

08-Nov-2023 - Title updated. Wording clarified.
26-Jun-2023 - This errata KBCN separated from KBCN1336.

NABERS – Compliance with the requirements of Ene 01 - KBCN1463

Undertaking energy modelling for NABERs (DfP process) can be used to demonstrate compliance for the 4 predicted energy modelling credits and also the 2 exemplary credits for committing to post-occupancy measurement of energy.

On-site LZC – whole site shared connection - KBCN1424

To be recognised in BREEAM, the on-site Low and Zero Carbon (LZC) technology must have a direct physical connection to the assessed asset. OR Where the LZC technology is;

Located on the same site,
Is owned and managed by the same organization as the assessed building, and
Where it is impractical to physically connect the assessed building to the system,

It is acceptable to allocate the renewable energy generated proportionally as a calculation of the asset's predicted energy consumption compared to the total energy consumption of the whole site. To allocate renewable electricity by proportional consumption:

Obtain the total annual renewable electricity generated on-site.
Exclude all renewable electricity which has been exported to the grid.
Determine the respective electricity consumption of all assets on the whole site (predicted for new builds and measured for existing assets).

Where consumption data is missing, renewable electricity must not be allocated to the assessed asset. In this case, it is assumed that all electricity consumed is sourced from the grid.

17-Jan-2024 - Applicability BIU V6 Ene 13 removed, as this approach is not applicable to assessing the area of PV fitted.
21-Dec-2022 - Applicability to In-Use V6 confirmed.
24-Aug-2022 - Applicability to UKNC V6 confirmed.

Parts of the building not subject to national thermal regulations - KBCN0534

Where you have parts of the assessed building which are not subject to national thermal regulations then these should be omitted from the EPR calculation.

24/08/2022 - Applicability to UKNC V6 confirmed

Prediction of operational energy consumption – Multiple (similar) buildings assessments - KBCN1479

Sampling is not appropriate to meet the aim of the criteria; it is necessary to model the predicted operational energy consumption of all assessed units. Credits are awarded for undertaking the detailed modelling, therefore there is no requirement to identify the worst performing unit and KNCN1382 is not applicable.

24/08/2022 - Applicability to UKNC V6 confirmed

Prediction of operational energy consumption – alternative route to Excellent minimum standard - KBCN1336

Where the ‘Prediction of operational energy consumption’ criteria are achieved, the minimum standard for Excellent in Ene 01 is met. This is independent of meeting any minimum credit score in the issue to achieve the Excellent minimum standard. See KBCN1602. Substantial improvement To meet this minimum standard, the asset must show a substantial improvement in operational energy performance, following the ’Prediction of operational energy consumption’ criteria. This 'substantial improvement' is defined as achieving 4 credits using amended metrics generated using the dynamic simulation modelling and for:

UK: the Ene 01 methodology that applies to your scheme version.
International: assessments using the Option 1 approach.

Amended definitions Performance is calculated based on amended definitions of an actual and a notional building: Amended actual building:

Actual fabric.
Expected actual occupancy.
Actual building servicing systems.

Amended notional building:

Notional fabric.
Expected actual occupancy.
Notional building servicing systems*.

*The notional building servicing system may be replaced with a gas boiler as the heat generation source. Where the performance improvement over the amended notional building does not achieve 4 credits, the BREEAM Excellent standard may still be met. Robust evidence must be provided showing that this level of performance improvement is not possible, based on constraints outside of the control of the project team. Additional notes for UK schemes Projects assessed under UKNC V6.1 can manually input amended figures from the modelling into the platform to demonstrate the 'substantial improvement'. See "DSM Alternative Ene 01 inputs" in BREEAM Projects for this issue. For the energy modelling and reporting criteria, the CO₂ metric can be calculated using either:

The CO₂ and primary energy factors for the Buildings Regulations version specified in UKNC 2018 / V6 or,
Using SAP 10.2 emission factors. The Government’s Standard Assessment Procedure for Energy Rating of Dwellings Version 10.2 (17-12-2021) https://files.bregroup.com/SAP/SAP%2010.2%20-%2017-12-2021.pd

08-Nov-2023 - Additional wording and link to KBCN1602 added to clarify situation for UK simple buildings.
26-Jun-2023 - Content updated to apply to International schemes. Title and wording clarified. Text on manual errata in NC 2018 3.0 moved to KBCN1602.
14-Jun-2023 - Note added to confirm this is integrated into the platform for UKNC V6.1 in all countries. 
24-Aug-2022 - Content updated and applied to UKNC V6
19-Aug-2019 - Clarification for UKNC 2018 3.0.

Prediction of operational energy consumption – risk assessment - KBCN1477

The risk assessment ensures that the asset (as designed) is able to achieve the predicted performance. It identifies where differences between the design assumptions and the operational situation could negatively impact on energy performance, and proposes how these risks can be managed. The risks that should be considered may include: - Product specification and the management of value engineering decisions. - Construction and installation considerations, particularly for complex or novel systems. - Sensitivity to occupancy assumption (particularly for speculative projects). - Appropriate commissioning of servicing systems. - Making sure end users know how to operate the building as intended. For risks that cannot be directly managed by the design team, (and may, for instance, be under the control of the contractor or asset owner), evidence should be provided showing how the recommendations of the risk assessment are communicated to these parties, and any agreed actions. The risk assessment is not intended to be a complex document. It is a list of risks to changes in the design, and how they will be managed in a practical way. The format of the risk assessment can vary, and could include: - Annotations or comments in the energy modelling report. - An addendum to the energy modelling report. - A separate document. If the risk assessment is part of another document, relevant sections and comments should be clearly highlighted so that QA can identify how the intent of the criteria has been met.

Preliminary design workshop – RIBA stage requirement - KBCN1207

In Issues 1.0 and 1.2 of the technical manual, Criterion 2 appears under the heading 'Prerequisite' and must be completed prior to the end of ‘Concept Design’ stage. Clarification of the requirements in Ene 01: The prerequisite currently states: ‘2. Prior to completion of the Concept Design, relevant members of the design team hold a preliminary design workshop focusing on operational energy performance.’ Clarified criterion (superfluous reference to 'Prerequisite' removed): ‘2. Involve relevant members of the design team in an energy design workshop, focusing on operational energy performance (see Methodology).'

This will be confirmed in the next re-issue of the technical manual, but can be applied immediately in all issues of the UK NC2018 scheme.

Registering assessments to UK NC2018 or UK NC V6 – Version of Part L - KBCN1535

BREEAM UK New Construction 2018 was developed for buildings in England which are demonstrating compliance against Part L 2013. The New Construction V6 version is intended for buildings in England which are demonstrating compliance against Part L 2021. Accordingly, UK NC 2018 will only accept 'inp' files created using Part L 2013 building regulations software for England and UK NC V6 will only accept 'inp' files created using Part L 2021 building regulations software for England. Assessments already registered to BREEAM UK NC 2018 that must comply with the Part L 2021 of the Building Regulations may follow either of the options below:

Transfer to the UK NC V6 scheme
Assess under UK NC 2018 and do two Part L models:

- Part L 2021 for statutory compliance
- Part L 2013 for BREEAM purposes

New assessments subject to Part L 2021 may register to UK NC V6 or follow Option 2, above.

10 Feb 2023 - Applied to Issue Ene 01 to improve visibility

Shell only – Installation of building services - KBCN00078

Content removed. Please refer to KBCN1488 for more comprehensive guidance.

Shell only – retail glazing not within scope - KBCN0937

Where a retail building envelope is not complete and glazing will be provided by the future tenant/(s), there are two options available: A 'Green fit-out agreement' (see Definition under this Issue in the technical manual) can be used to ensure that the performance level of the glazing used in the energy model is met in the completed building. This must be accompanied by evidence that the performance of the assumed glazing does not impose overly onerous requirements on future tenants and that it falls within the scope of glazing typically used in retail developments. Alternatively, the assessment can be based on worst permissible performance under the relevant national building regulations. In all cases, for shell only assessments, the assessment method detailed in CN1 (for UK New Construction 2014 and International New Construction 2016) and Assessment type specific note 1.3 (for UK New Construction 2018 and UKNC V6) must be followed.

24/08/2022 - Reference and applicability to UKNC V6 added
14 11 2017 Wording amended to clarify the intent

Shell only – zero net regulated carbon emissions - KBCN1101

For Shell only projects, 9 credits can be awarded when the EPR_EDratio is 0.90, without the requirement for zero net regulated CO₂ emissions applying. Shell only projects only assess the buildings heating and cooling energy demand and so credits are awarded just on this basis.

24/08/2022 Applicability to UKNC V6 confirmed

Shell only – Energy modelling requirements - KBCN1488

For a shell only assessment, only the EPR demand metric is used to determine the energy performance. Therefore, we would not expect to see improvements to equipment and services accounted for in the BRUKL/NCM calculation. It is, therefore, recommended that assessors submit a BRUKL/NCM document incorporating the fabric improvements, but which retains the equipment and services of the notional building with heating and cooling provided by multi-split systems. Credits for shell only assessments are determined by the demand metric alone. The inclusion of more efficient equipment and services may, therefore, lead to lower heat gains, a subsequent increase in demand for space heating and, hence, a lower number of credits being awarded.

28 Aug 2022 - Guidance updated and applied to UKNC V6

Similar speculative developments (Shell and Core) - KBCN1382

For speculative, Shell and Core projects there will be a significant level of uncertainty regarding equipment loads and usage patterns. Project teams should make the best estimates they can based on available data for similar projects, instead of using the National Calculation Methodology occupancy assumptions. Where sites have multiple speculative, Shell and Core buildings it is acceptable for the 'Prediction' work to be the same across all the units. The design team would need to be sure that all the units would have the same type of tenant and be used in the same way. This is in keeping with the aim of the 'Prediction' credits; to predict energy consumption as accurately as possible. If the users are known to be different, this approach would not be acceptable.

24/08/2022 Applicability to UKNC V6 confirmed

Statutory requirements for energy modelling differ from BREEAM - KBCN0127

For the purposes of BREEAM, Issue Ene 01 should be assessed using a BRUKL output based on the prevalent UK country Building regulations applicable to that scheme. This applies even when the building does not need to undertake energy modelling to comply with Building Regulations.

Where a different analysis is required for statutory compliance, due to the location of the project or registration to an earlier or later version of Part L, a different output must be produced for this purpose.

Alternatively, where applicable, the BREEAM registration could be updated to the latest version, so the same energy model output can be used for both purposes. To maintain consistency and comparability for all assessments registered to a scheme.

24/08/2022 Applicability to UKNC V6 confirmed

Use of as-designed BRUKL output for post-construction submission - KBCN0889

Where it is not possible to produce an as-built BRUKL output for the post-construction assessment, it is acceptable to produce an updated as-designed BRUKL output that accurately reflects the constructed building as evidence for the post-construction submission. A justification should be issued to QA clarifying why an as-designed BRUKL was submitted, along with confirmation from the relevant specialist that the model is an accurate representation of the final, as-built specification of the building.

24/08/2022 Applicability to UKNC V6 confirmed

[KBCN withdrawn] ~ Exemplary credit – Beyond zero net regulated carbon/carbon negative – Software output figures - KBCN1094

This KBCN has been withdrawn and is no longer valid. This is because its content is not relevant to the exemplary credits, which are based solely on carbon emissions, nor for standard credits, which are based on BRUKL inputs.

KBCN withdrawn on 05/08/2019:

For the 'Beyond zero net regulated carbon/carbon negative' exemplary credits, in order to demonstrate that up to three exemplary level credits can be awarded for Ene 01, the primary energy generated by the carbon neutral technologies will need to be calculated by applying the relevant primary energy factor.
These figures are taken from the approved building energy calculation software output.
For guidance on completing this calculation and to obtain primary energy factors please contact BRE Global.

New Construction / UK / 2018 / 03 Energy /