We need to upgrade about 1 dwelling every minute of the day for the next 35 years to meet the UK's 2050 targets.
This post first appeared on March 11th at the Online RIBA Journal under the title 'One step forward, two steps back', where I look at the danger of unintended consequences to energy efficiency measures.
Some 25 million existing dwellings will need to be upgraded by 2050 as part of the UK’s move towards a low carbon economy and built environment. To illustrate the sheer scale of this challenge, that means we need to upgrade about one dwelling every single minute for the next 35 years.
From an energy, thermal comfort and fuel poverty point of view, buildings should be upgraded to the highest affordable standard. Given the significant scale and urgency of this national task, buildings should be given this substantial fabric upgrade only once during this time, reducing occupant hassle factor, disruption, cost and resources. However, retrofits could be undertaken step by step: partial refurbishment of fabric elements as and when replacement and upgrade is required, but always as part of a whole building masterplan. It is crucial that the whole building is considered during retrofit design, owing to the complexity and interaction of different measures. This supports the minimisation of unintended consequences arising from upgrading or ‘fixing’ one thing but causing issues elsewhere. This applies even if only parts of the building are upgraded or where a refurbishment is carried out step by step.
Unintended consequences can already be an issue with simple building maintenance – for example addition of impermeable materials; repointing with cement mortar and old cement render causing brick degradation behind cracks.
External cork wall insulation on retrofit of Victorian end-of terrace house by Venner Lucas Architects. Cork is a breathable material and considered more robust in retrofit applications.
In particular, when undertaking more substantial upgrades, occupant health needs to be protected. For example, sufficient and controlled background ventilation – such as MVHR or continuous MEV (mechanical extract ventilation) – must be provided when a building is being made more airtight by additional insulation and/or sealing gaps and cracks in our quest to save energy and increase thermal comfort. Doing so will avoid excessive moisture and pollutant build-up which affect human health. Equally, retrofit details, finishes and execution are crucial to avoid thermal bridging and surface and interstitial condensation, with consequent fabric degradation and mould growth/timber rot. Failure to apply such measures would affect human health and the need for future repairs would be likely.
Another unintended consequence of fabric upgrades could be futuresummer overheating: a well-insulated fabric keeps the heat both in andout. However, where a highly insulated fabric has not been combined with solar shading, internal temperatures may become excessive in summer, again affecting human health and negating any energy savings if active cooling is introduced.
Finally, we should not assume that upgrading buildings automaticallyleads to energy savings. A whole host of issues such as design, lack of suitable predictive energy-use modelling tools, installation, workmanship, commissioning, complex user controls and user behaviour can lead to smaller than expected energy-savings. This highlights the importance of careful design and consideration of the above, while also acknowledging that the benefit to the occupants is not simply lower energy bills, but also increased thermal comfort and better health – impacts which cannot be measured in CO2 but which are nevertheless important and are additional drivers of upgrading existing buildings.
Note: a free STBA/DECC online tool can help to make more informed decisions; it attempts to highlight the complexity of inter-related issues and potential unintended consequences: www.responsible-retrofit.org/wheel.
This opinion piece first appeared at the RIBA Online Journal 25.02.2015.
When I studied in the mid-90s for my architecture degree in Belgium, I did not fit in for many reasons. One was that I was always interested in adaptive reuse of existing buildings while most of my peers could not fathom why I would be interested in the constraints of existing buildings which ‘would never have my name on them’. But it appears that little may have changed in the past 20 years, even in the UK. Sir Terry Farrell’s 2014 review of architecture and the built environment observed that ‘refurbishment and retrofitting had not been considered to be architectural issues, and these concerns still struggle to be accepted as legitimate by the architectural community’.
Yet architects have a crucial role to play in reuse, adaptation and upgradeor retrofit of existing buildings: there are some 27 million existing buildings in the UK alone, most of which are dwellings, and 75% of which will still be standing by 2050. The need for extensive retrofit of these to nearly zero energy standards by 2050 is undeniable in a changing climate: occupants in these warmth-leaking buildings rely on burning CO2-intensive fossil fuels, leading to climate change, unaffordable heating bills and lack of thermal comfort.
Ferrier point is a 23 storey, 1968 built residential tower in Newham, one of the few of its kind to not have been demolished. Can the need for sustainable retrofit also be an opportunity to enhance the architectural quality of the building? Ferrier point was upgraded with new windows, externally insulated metal rain screens and 370m2 vertical PV panels, all installed while residents remained in-situ. · Credits: ©ECD Architects
Yet the expectation, work and self-image of most architects is associated with designing new buildings. This new-build focus is a missed opportunity for architects, both commercially and as an opportunity to lead and shape the debate of how to transform our existing buildings and their legacy. The sheer scale of the task ahead and the number of existing buildings which need improvement require architects to lead this transformation with their imagination, project management skills and technical expertise.
But this requires a significant shift in priorities and approaches in both practice and in teaching, where low-energy refurbishment, heritage and building conservation are usually not part of the agenda, as also noted by Farrell.
Yet, we need innovations, new solutions and creative approaches, alongside evidence-based reviews and critiques to support this real, pressing and large-scale upgrade of our built environment. Architects and designers are well placed to help deliver such an ambitious retrofit plan, says Farrell, by ‘making efficient and holistic decisions on any scale of project, while understanding the broader conservation issues.’
For architecture to remain relevant to society, architects need to adjust our self-image from creators of the new to also being updaters of the old, both through education and by challenging ourselves and others about retrofit approaches and design strategies.
Architectural professionals and educators have an opportunity to be involved in this transformation of our built environment and to establish a new ‘retrofit poetic’. What are we waiting for?
[Download Farrell Review here and executive summary here as PDF]
Firstly – another big thank you to Saint Gobain and ECD architects who sponsored our workshop ‘ Retrofit in practice what next?’ at the Industries of Architecture Conference at Newcastle University Nov 14th 2014. [a shorter version also appeared on the UCL Energy Institute's blog]
Our workshop was set against the background of the UK’s ~26.7 million existing dwellings and 1.8 million non-domestic buildings. The energy use of housing alone, which is mostly used to keep people warm in their homes, contributes to about 1/3rd of the UK’s carbon emissions. So there is a real urgency to reduce this energy use in buildings: thermal comfort of occupants, avoiding fuel poverty, aesthetic upgrades as part of building maintenance when buildings meet or exceed their intended lifespan, and ofcourse also stopping the reliance on burning fossil fuels to operate and construct these buildings, which are a finite resource and contribute to global warming.
The UK, and the rest of Europe needs to reduce the carbon emissions from this energy use to pretty much zero in the existing building stock by 2050, while new buildings will have to meet that standard much earlier (before 2020). To illustrate the scale of the problem: there are more existing buildings that need to be upgraded monthly to meet this target than there are new build buildings built yearly in the UK.
This brings with it a whole host of challenges, but also opportunities and this is what we really tried to capture in our workshop. Many of the contributions pointed towards solutions by raising relevant questions. By doing that, the presenters also touched on key issues that are related to the retrofit challenge.
Some topics that were raised included: project management, skills gaps, assessment methods, new models and tools, procurement, testing performance, community benefits, unintended consequences of retrofit, aesthetic consequences and approaches, and lets not forget the people who live and work in these buildings, and ofcourse the architect’s role in this process.
A quote from Sir Terry Farrell’s review of architecture and the built environment earlier this year for government touches on this last point. He stated: “An architect can add value to retrofitting by making efficient and holistic decisions on any scale of project, while understanding the broader conservation issues.”
Other questions that were raised were:
During discussion, it became clear that terms such as ‘retrofitting’, ‘conservation’ and ‘heritage’ have overlaps but are also not clearly defined at the moment.
For example what do we mean by conservation and heritage? What is the value in listed buildings we are trying to protect, is it the entire building or a specific aspect? And, if it is only part of a building that is ‘valued’, perhaps listed building consent – considered a barrier to upgrading buildings – may not be necessary at all?
What do we mean by retrofitting? Does retrofit mean just adding, or changing, or can it also mean taking away? Or any of these together? Does retrofitting include renewable technologies as add-ons such as solar panels on a roof? Or is retrofitting’s key concern the fabric upgrade?
Should we not touch a heritage building at all? Or is wrapping the building in a new protective, ‘conserving’ layer part of conservation, as it increases the durability of the building and retains, protects, ‘conserves’ its structure and purpose? In particular, which parts can we touch and which do we need to leave untouched? Should we make a clear distinction between old and added or should the added match the existing?
Ofcourse some of these issues are subjective, even emotive, but little discussed in depth so far in industry or academia. Perhaps as academics and practitioners it might be timely to consider more consciously the terminology, and our own conceptual approach to retrofitting. What are the consequences for the way we design? does the need for sustainable retrofit require us to critically re-examine some dearly held architectural concepts?
On the other hand, some argued, given the sheer scale and urgency of the task ahead for many buildings which are not listed, we might just need to get job done. If millions of housing are not of any significant quality or aesthetic, can we use the need for sustainable retrofit as an opportunity to enhance the architectural quality of our buildings?
So, there is a huge opportunity for architects, one where we can think creatively, innovatively and imaginatively and establish a new ‘environmental architecture poetic’, but architects, and architecture education, appear to be missing this significant and real opportunity. To quote Sir Terry Farrell again: “refurbishment and retrofitting had not been considered to be architectural issues, and these concerns still struggle to be accepted as legitimate by the architectural community”.
He also suggested that: “Architecture schools should include refurbishment and low-carbon retrofitting of old buildings in their curriculum and project work and conservation and heritage issues in course content.”
So, to close our summary, we hope that this is something we can all work towards changing, because retrofitting buildings is real. It is urgent. It is important. It offers great opportunity for a new architectural paradigm. Retrofitting is ‘what is next’ in architecture for our buildings. Basically it is here to stay, and we need all of you in academia/heritage/practitioners/industry involved. We need to want to be involved in this – for architecture to remain relevant to society.
Sofie Pelsmakers & Dr David Kroll, drawn from discussion with speakers listed here.
Download statement and speaker profiles as a PDF.
DECC UK National Energy Efficiency Action Plan (incl. building stock profiles)
BPIE data hub on EU's existing buildings & policies
CCC Review of potential for carbon savings from UK residential energy efficiency
Retrofit for future
SuperHomes case studies
BPIE RENOVATION STRATEGIES OF SELECTED EU COUNTRIES
STBA/DECC Responsible Retrofit of Traditional buildings report and guidance wheel and knowledge hub
Historic Scotland technical guides
English Housing Survey