7. Sustainable Renovation Planning – How to Repair Buildings
Mira Kyllönen
Mira Kyllönen is an architect working with renovations and historic building evaluations. She is also a member of the Finnish Association of Architects’ Repair Construction and Built Heritage Committee.
At the Arkkitehtipäivät [Architecture Days] seminar held in Helsinki, Finland, in May 2021, researcher and architect Satu Huuhka from Tampere University gave a powerful speech on the circular economy in the construction sector. During her speech, Huuhka mentioned, that many architects long for construction methods that utilize natural materials, which can be returned to the natural cycle, should the building be demolished. According to Huuhka, virgin raw materials should not be used for construction at all. Instead, the existing building stock should be utilized and looked after.
The report To demolish or to repair? (Finnish: Purkaa vai korjata) (1) written by Huuhka and her research group and published by the Finnish Ministry of the Environment in 2021 says: “In order to fight and adapt to climate change, we must avoid causing carbon emissions especially over the next few decades. Based on the studied cases, renovation does this more effectively than demolishing an existing building and replacing it with new construction.”
Ergo, in comparison to new construction, renovation stands at an advantage regarding sustainability; when the assumption is that emissions need to be reduced now, renovation makes sense, as it takes years for improved energy efficiency to make up for the spike in carbon emissions that new construction generates.
However, not all repairs are sustainable. According to the Ministry of the Environment, the building sector generates 35% of greenhouse gas emissions and 30% of waste worldwide. Only 15% of this waste is generated by new construction, with the remaining 85% of construction and demolition waste being caused by renovation and demolition projects. Currently repairing produces substantial waste. (2)
Repairing or renewing
What is a repair? Maybe one of the following:
Maintenance (e.g. painting)
Fixing up
Conservation
Restoration
Preservatory repair
Restorative repair, reconstruction
Layout adjustments (e.g., the demolition and construction of partitions)
Complete renovation, or refurbishment
Extensive renovation (comparable to new construction), where all technical installations in the building are renewed
Changes in use
Repair of an (old) building and expansion of it
Construction by utilizing an existing load-bearing frame on site
New construction using recycled construction parts (e.g. an existing and relocated log frame)
Demolition of the existing and replacing it with new construction
I invite the reader to mentally draw a line on the list where repair ends, and construction begins. Or to evaluate point by point which category each intervention falls into.
It is interesting to consider what is expected of a renovation. A restoration is successful, when users notice no change, even after considerable work has been done. Hanna Lyytinen gives an example of such a case in the interview “The Sacred Remains” published in the Finnish Architectural Review 3/2021 (3): “In the midst of constant changes, Lyytinen’s experience is that parishioners long for permanence. Her goal, then, is for the necessary changes to be so natural that parishioners may not even notice that anything has changed.”
Contrary to restoration, “fixer-uppers” are expected to produce a wow-effect as seen on renovation or interior design programs on TV, where the owners hardly recognize their own home after it has passed through the hands of a professional. Viewers and homeowners expect a transformation, but why is the presented solution so often generic, indifferent to site or context?
Could the starting point of renovation be to reveal the essentials and to underline the fundamental spatial characteristics? Instead of radical changes, the building could be left in a state where visitors are able to read its stories, perceived perhaps through a cherished patina.
Instead of repair, many extensive projects undergo renewal. Sometimes the facades need to be preserved, for instance, due to conservation regulations, but everything else (partitions, floors, interiors, the roof) is redone. Occasionally, “to repair” means to change for something new by replacing the original repairable building component with a new unrepairable one. This is typical for windows and floor materials for instance, where wooden windows are substituted with wood-aluminium ones and parquet is replaced with laminate or another plastic product.
In an article published in the Finnish Architect news AU 3/2021 (4), Miia Perkkiö concludes: “Could renovation not also utilize restoration principles, instead of renewing buildings into a soulless state.”
For the various ways to renovate to become part of the discussion, I suggest that for projects that deal with the existing building stock, the terms renewing renovation and preservatory renovation should be used. A distinction, in percentage, for instance, would be made to describe to what extent the building is:
preserved
repaired
altered
renewed
Renovation objectives
It is widely thought that the most valuable old buildings, which are protected by law, are the kind to be restored. In Finland, these buildings constitute 2% of the building stock. Restoration, or conservation, is preservatory repairing, where all existing material has value. At a time, when we have acknowledged the need for significant emission reduction in the construction industry and are aware of the amount of waste generated by complete or renewing renovation, we cannot limit restoration practices to specific sites only. We must treat the entire existing building stock with the same level of respect. So let’s only undertake the most necessary measures. Let’s keep buildings in use, care for them, and maintain them. Let’s keep renewal to a minimum and when a building is indeed renewed, let’s use materials that can be repaired in the future and components suited for the building.
Conservation and sustainable repair are not easy. For instance, surface materials dismantled to enable structural repairs take up a lot of space when cleaned and stored on the construction site (or in another temporary location) for the entirety of the renovation instead of being taken to a landfill. Structures that are not dismantled need to instead be vigorously protected from the wear and tear of everyday life of a construction site so that they do not need to be replaced in the end. The availability of recycled building components and storage of them also pose challenges. A cultural shift in renovation clearly requires construction sites to develop and implement new processes.
Not all buildings are in such condition, that preservatory renovation is possible. If careful consideration results in the conclusion that only renewing renovation is possible, then let’s rather do that, than demolish an entire house. And obviously, when embarking on such a renovation let’s make sure to use materials and components that can be repaired in the future.
When implementing renewing renovations, it is time to forget the prevailing narrow-minded and unimaginative aesthetic and instead celebrate historical layers and the appropriate styles (and recycled components) of each decade. Let’s acknowledge that one-size-fits-all does not work.
Renovation of new buildings
As I pointed out previously, it is sometimes hard to draw the line between renovation and new construction. It seems, however, that designers of new buildings often want to distance themselves from renovation. Why even try to pit new construction against renovation? Every renovated building has once been a new building. Instead, we need to understand buildings and construction as a whole and look at how to reduce the overall emissions.
If the design of new construction does continue, even after we have established that it does not make climate sense, we need to focus on how these new buildings will fare in the future. And I do not merely mean the timelessness of the massing or façade composition but also how the building as a whole, including its structural solutions and material choices, will fare over time.
An article on the Zero Arctic study conducted by the Finnish Ministry of the Environment, published on the Finnish Architectural Review 2/2021 (5), discusses the resilience of buildings: “Resilience refers to the ability to remain functional in fluctuating conditions and to withstand change. … Climate change will bring about unpredictable weather conditions, which means that buildings will need to be designed to be repairable, fault-tolerant, and easily maintainable, and they need to allow for flexible utility in varied situations and weather conditions.”
Having established that renovation makes more sense than demolition and new construction, I disagree with those that advocate for building design to adapt to the ever-increasing speed of change by designing new buildings for temporality and demolition. Instead, we need to design for permanence both in new construction and renovation. When a building is designed and implemented for resilience, it also enables future renovations to be restorative and require minimal intervention.
references
1 Huuhka, Satu et al. 2021. Purkaa vai korjata? [To demolish or renovate?] Finnish Ministry of Environment. Available at: http://urn.fi/URN:ISBN:978-952-361-221-1
2 https://ym.fi/rakentamisen-kiertotalous
3 Oikarinen, Essi. 2021. The Sacred Remains – Interview with Hanna Lyytinen. Finnish Architectural Review. Vol.3. 44-49
4 Perkkiö, Miia. 2021. Korjata vai restauroida – korjausrakentamisen ikuinen dilemma. [Renovate or restore - the eternal dilemma of repair construction]. Arkkitehtiuutiset [Finnish Architecture Bulletin]. Vol 3. 20-23.
5 Huttunen, Marko et al. 2021. Zero Arctic. Finnish Architectural Review. Vol 2. 36-39.
