PAS 2035
PAS 2035:2023 Retrofitting dwellings for improved energy efficiency - Specification and guidance is one of a number of Publicly Available Specifications covering retrofit, refurbishment and building upgrades. The others public specifications include; PAS 2030:2023 Installation of energy efficiency measures in existing dwellings and PAS 2038:2021 Retrofitting non-domestic buildings for improved energy efficiency.
PAS 2035:2023 (Incorporating Corrigendum No. 1) Retrofitting dwellings for improved energy efficiency – Specification and guidance describes retrofit building physics, building pathology, thermal models and calculations, approaches to retrofit in the medium term and at scale, performance considerations, standards and constraints, fabric first, interfaces, wholedwelling assessments, distressed replacement, retrofit designs, testing, commissioning and handover. It also also describes the various retrofit related roles, such as the main contractor and retrofit installer, retrofit advisors, coordinators, assessors, and evaluators aswell as standards, frameworks, competency and qualifications relating to these roles.
The PAS document says "Statutory national targets for the reduction of greenhouse gas emissions in response to the threat of climate change imply that very significant improvements need to be made in the energy efficiency of the UK’s building stock, including nearly all its 27 million domestic buildings. The Climate Change Committee sets “carbon budgets” under the Climate Change Act 2008, and the Government’s Net Zero Strategy includes a commitment to improvements in Energy Performance Certificate (EPC) scores in existing dwellings." It goes on to say that it "supports work towards those objectives by promoting and defining technically robust and responsible “wholedwelling” domestic retrofit work, i.e. highquality work that supports:"
- "a) improved functionality, usability and durability of buildings;
- b) improved comfort, health and wellbeing of building occupants and visitors;
- c) improved energy efficiency, leading to reduced fuel use, fuel costs and pollution (especially greenhouse gas emissions associated with energy use);
- d) reduced environmental impacts of buildings;
- e) protection and enhancement of the architectural and cultural heritage as represented by the building stock;
- f) avoidance of unintended consequences related to any of the above;
- g) minimization of the “performance gap” that occurs when reductions in fuel use, fuel cost and carbon dioxide emissions are not as large as intended or predicted; and
- h) protection of the general public and the client in relation to retrofit work."
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