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SESSION 5

Retrofit vs Rebuild:�Unpicking the carbon �argument

28^th March

www.leti.uk

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Agenda

Introduction

01 Retrofit vs rebuild unpicker

Q&A

LETI events

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Operational energy modelling guidance
Demolition/retrofit
Circular Economy
Energy from Waste
And more!

More sessions coming soon!

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4

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Whole life carbon

Building regulation compliant building

Net zero operational carbon

Circular economy

Current buildings

Whole life carbon

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Retriofit vs rebuild unpicker

01

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Retrofit vs Rebuild

Does the whole life carbon assessment and comparison of Retrofit vs Rebuild scenarios

provide a basis for decision

on the carbon part of the retrofit versus rebuild argument?

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Retrofit vs Rebuild

Carbon

Value e.g. heritage, value to community

Functionality and performance

Other sustainability considerations e.g. climate resilience, water use, biodiversity

Carbon = what the unpicker covers

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Retrofit vs Rebuild

Assessments of embodied and operational carbon are complex

Both rely on assumptions

The comparison of scenarios can be difficult, to establish the best option

Does the whole life carbon assessment and comparison of Retrofit vs Rebuild provide a basis for decision

on the carbon part of the retrofit versus rebuild argument?

As fair and like-for-like as possible

Technically robust, thorough, and following best practice guidance

Transparent e.g. clearly listed assumptions, open about areas of uncertainty.

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Retrofit vs Rebuild

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Retrofit vs Rebuild

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Q&A

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LETI is a network that was born out of desire to improve the knowledge of low carbon buildings. We started in London, but as we grew as a network, our influence increased to be UK-wide. Recognising this, we changed our name to the Low Energy Transformation Initiative last year.

We want to start to build up a greater representation of the wider UK built environment industry, helping us to be far more relevant to those areas outside of London. The first part of this is our LETI Roadshow, with local, in-person events across the country, bringing together local leaders and enthusiasts on climate-aware design.

To begin we’ll be hosting events in Edinburgh, Manchester, and Cardiff and more where we’ll present a some of the exciting work that LETI has produced, as well as updates from the workstreams that currently producing new guidance and research.

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Webinar on the 28^th of March

Consultation closes 18th April 2023

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Webinar on the 28^th of March

There are 3 carbon conversion sets for converting operational energy into operational carbon.

Set 1 is used to understand the whole life carbon consequences of design decisions ( e.g. additional insulation, or heating system type)

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Thank you!

see you on the 18^th April!

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