Methodology for establishing (Non-Residential & Residential)building proxies
ABSTRACT: The two methodologies for establishing proxies explained through examples
Document Updated: Dec 2016

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1. Introduction
There are two methods available to establish proxies for Non-Residential and Residential Buildings for the purposes of
Climate Bonds Certification.
The two methods are:1. Benchmarking against local market emissions performance
2. Proportion of total ratings/labels awardedThis document explains the two methodologies through the use of examples.

2.1. Benchmarking against local market emissions performance
The first step is to use available data to determine the emissions performance of the top 15% most energy efficient buildings(of a particular type e.g. offices) in a local market. The emissions performance of the top 15% forms the start of an “emissionsperformance trajectory” that declines to zero carbon emissions in 2050.
Data used to establish the emissions performance of the top 15% most energy-efficient buildings must satisfy the following
requirements:- It originates from a reliable source.
- There must be a sufficient sample of buildings that is representative of the market.
- Building emissions performance must reflect emissions for the full fuel cycle (scope 1, 2, and 3).
- Building emissions performance must relate to operational performance not modeled performance.
- Building emissions performance is expressed on an annual basis in kgCO2 terms.
Data could relate to statistical results from a local market survey (where the top 15% has been determined) or a raw data setof individual building emissions performance. The document “Methodology for establishing emissions performance
trajectories” provides further details on calculating the emissions performance of the top 15% using raw data.
For a proposed proxy (i.e. building standard, code or rating) to be approved by CBI, there must be evidence to demonstratethat it delivers building emissions performance in line with the emissions performance trajectory.
Sunset dates are set for proxies when they are approved to specify when they will no longer have effect. This is due to theapplication of an emissions performance trajectory that declines to zero carbon emissions in 2050, creating more stringentemissions thresholds that proxies have to satisfy to remain valid.
This method for establishing the validity of a proxy is more relevant for Residential Buildings than for Non-ResidentialBuildings.
If a reliable emissions performance trajectory can be created for a non-residential building type in a city, there really is no needfor a proxy because CBI favours the emissions target method to the proxy method for certifying Non-Residential Buildings.
The documents “Non-Residential Buildings Criteria” and “Non-Residential Buildings – Discussion Notes” provide further
information on the two certification methods and explains the rationale behind them.

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2.1.1. Example – Local building code and 3-bedroom dwellings
In a local market, the emissions performance of the top 15% most energy-efficient 3-bedroom dwellings is 2,170 kgCO2..
In 2015, a local building code requires a minimum 60% reduction against the average emissions performance of threebedroom dwellings (4,650 kgCO2).
As the local building code requires an emissions performance below 1,860 kgCO2 (4,650*[1-60%]), which falls under theemissions performance of the top 15% (2,170kgCO2), it aligns with the emissions performance trajectory (see diagrambelow).

As the emissions performance trajectory declines to zero carbon emissions by 2050, it means that the emissions thresholddetermining the validity of a proxy declines over time such that proxies are only valid for a certain time period. For thatreason, sunset dates are set for proxies when they are approved, which specify when they will no longer have effect.
Carrying on with the same example, the emissions performance trajectory (see diagram below) indicates that the emissions
threshold (i.e. performance of the top 15%) declines to 1,860 kgCO2 by 2020 (i.e. the performance required by the local
building code). From 2020 onwards, the local building code will therefore no longer be sufficient to deliver emissions
performance in line with the emissions performance trajectory (as the emissions threshold declines below 1,860 kgCO2).

For this example, the sunset date for the local building code is the year 2020.

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2.2. Option B: Proportion of total ratings/labels awardedThis option offers a solution when data and statistics on the emissions performance of buildings in a local market are lacking.
For a proposed proxy (i.e. building rating or label) to be approved by CBI, there must be evidence to demonstrate that therating or label is in the top 15% of all ratings or labels awarded under the scheme (that predominantly rates buildings onenergy efficiency/emissions).
At a minimum, CBI expects the rating or labelling scheme:• To have an underlying register or database of verified energy/emissions performance data that enables analysis• To have an underlying register or database of a sufficient size that supports statistically significant conclusions• To have good market coverage and therefore, is representative and has an adequate spread of performance levels
Proxies established using this option are reviewed every 2 years to ensure that they are still valid.

2.2.1. Example – Labelling scheme and residential buildings
In a local market, a labelling scheme assesses the performance of residential buildings on an energy/emissions basis and awards
labels from A to G based on a building’s energy/emissions efficiency.
The database of this labelling scheme encompasses 2.5 million records from a total pool of 7.5 million assets nationally. As aperformance label is a mandatory reporting requirement at the point of sale or lease of a building, the scheme will likely bemore representative of the market compared to voluntary schemes. The local market distribution of labels also has a good
spread of performance labels from A to G (see diagram below).

Analysis of the labeling scheme’s data indicates that the highest efficiency ‘A’ label forms 9% of the total labels awarded (seediagram below). A verified ‘A’ performance label can therefore be said to align with the top 15% most energy-efficientbuildings in the local market.

As a ‘B’ performance label falls in the next 13% of total labels awarded (i.e. from the top 10% to 22%), achieving the ‘B’ label
does not guarantee alignment with the top 15% and therefore cannot serve as a proxy.

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