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."
[edit] Related articles on Designing Buildings
- Alterations to existing buildings.
- Do the building regulations apply to works to existing buildings?
- Demolition.
- Material amendment.
- Material change of use.
- Minor material amendment.
- Non material amendment.
- Change of use class.
- PAS 2038:2021 Retrofitting non-domestic buildings for improved energy efficiency.
- Planning permission.
- Permitted development.
- Principal designer.
- Renovation v refurbishment v retrofit.
- Retrofit.
- Retrofit projects and roles
- Types of work to existing buildings.
Featured articles and news
The UK’s largest air pollution campaign.
Future Homes Standard, now includes solar, but what else?
Will the new standard, due to in the Autumn, go far enough in terms of performance ?
BSRIA Briefing: Cleaner Air, Better tomorrow
A look back at issues relating to inside and outside air quality, discussed during the BSRIA briefing in 2023.
Restoring Abbotsford's hothouse
Bringing the writer Walter Scott's garden to life.
Reflections on the spending review with CIAT.
Retired firefighter cycles world to raise Grenfell funds
Leaving on 14 June 2025 Stephen will raise money for youth and schools through the Grenfell Foundation.
Key points for construction at a glance with industry reactions.
Functionality, visibility and sustainability
The simpler approach to specification.
Architects, architecture, buildings, and inspiration in film
The close ties between makers and the movies, with our long list of suggested viewing.
SELECT three-point plan for action issued to MSPs
Call for Scottish regulation, green skills and recognition of electrotechnical industry as part of a manifesto for Scottish Parliamentary elections.
UCEM becomes the University of the Built Environment
Major milestone in its 106-year history, follows recent merger with London School of Architecture (LSE).
Professional practical experience for Architects in training
The long process to transform the nature of education and professional practical experience in the Architecture profession following recent reports.
A people-first approach to retrofit
Moving away from the destructive paradigm of fabric-first.
International Electrician Day, 10 June 2025
Celebrating the role of electrical engineers from André-Marie Amperè, today and for the future.
New guide for clients launched at Houses of Parliament
'There has never been a more important time for clients to step up and ...ask the right questions'
The impact of recycled slate tiles
Innovation across the decades.
EPC changes for existing buildings
Changes and their context as the new RdSAP methodology comes into use from 15 June.