About concrete and architecture
This is a lecture about concrete and architecture. In this lecture, architect Kaisa Karvinen examines concrete, particularly as a modern material of industrial building production.
The manufacturing of prefab concrete elements began in Finland in the 1960s, after which a significant part of concrete buildings have been constructed of concrete elements in addition to casting them on site. But before I go into more detail on concrete, I would like to share a memory with you.
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I was hospitalised for a longer time once. In the second year of upper secondary school, I ended up in the Oulu University Hospital due to stinging lower back pain and high fever. My mother took me to the emergency department.
We spent hours sitting on a sofa by a wall in a waiting room with a low ceiling. My lower back was aching and I felt strange. The sofa we were sitting on had a metal frame but was padded, fluorescent lamps were hanging from the ceiling and the tiled floor was bright green. Before seeing a doctor, I had an appointment with a nurse in a tiny room. The nurse was sitting on the opposite side of a table and I sat on the other side with my mother. After describing my symptoms, the nurse went quiet for a little while and then asked me if it was possible for me to be pregnant. I said “I don’t think so, but it’s possible in theory”. The expression on my mother’s face turned from one of concern to shock.
I was admitted to an inpatient ward. I was lying on the bed and was taken to various examination rooms along the hospital’s underground hallways. The distances were long. Finally, I got a room of my own where I had to wait for surgery. The room had a light palette and there was a small washbasin on its corner. I was lying in bed and watching the sky from my window, how now and then a small cloud passed by, making the room go dark. In the afternoon, a doctor came by and told me my place on the waiting list for surgery had been cancelled and that I was going to be prescribed antibiotics for a urinary tract infection. I still lay in my hospital room for a few more days before being discharged.
A few years after my hospital visit, I began to study architecture. And now, when I think about that hospital, I notice how the things I’ve been taught at the university affect how I examine that building. Or buildings in general.
By a concrete scale model
Actually, you can come and sit a little closer, over here. Come so close that you can see inside this concrete model. This is a scale model of the Oulu University Hospital, or, to be exact, its concrete frame; its load-bearing pillars and the concrete slabs that rest on them. To be quite clear, this model doesn’t portray the hospital as a whole but only shows one of the wings of its paediatric ward. In real life, the hospital forms a much more extensive whole. The distance from one end of the hospital area to the other is around one kilometre. If a model had been created for the whole hospital, it would have been too large to fit into the room that we’re currently in.
The Oulu University Hospital was designed by Architect Reino Koivula and his office. When the design process was still ongoing, Koivula’s agency gave the hospital the working title “Where the little birds sing”. The hospital was completed in the 1970s and it can be examined as an example of a space for care in the modern era as well as more extensively as an example of modern architecture. When we talk about buildings of the modern era, we often say that they are machines that must be used correctly. They provide separated spaces for various areas of life, for rest, work and celebrations and for things like care, as is the case with this hospital here. The hospital building was used to provide a solution for how to provide care in this institution and organise the care related work.
Modern architecture has been criticised for aiming at maximum efficiency and a loss of personality, but at the same time, we should bear in mind that the goal for housing, for instance, was to optimise the equality that architecture enables. The state was strongly involved in steering construction. The aim was to provide everyone with material conditions for life that were as equal and similar as possible.
The duty of modern hospitals was to ensure that everyone has an opportunity to receive hospital treatment.
Design ideals and apparent neutrality
This scale model is cast from concrete. Indeed, concrete is the material used in constructing a significant share of buildings used for living and housing in the modern age. The development of the concrete industry in Finland in the 1960s and particularly in the 1970s enabled the construction of entire neighbourhoods of blocks of flats in just a few years. Even though concrete casting continues to also occur on-site and cast moulds built out of boards can be seen at bridge construction sites, for example, a considerable part of concrete construction has been based on element production since the late 1960s. As the structure of society was changing, the number of employees in the service industry was increasing. People were moving into cities. There was a demand for homes. Housing estates and suburbs were built.
Concrete was changing both housing and cities and influencing what kinds of spaces designers aimed to create. Concrete was changing the ideals of design. The flat-slab floor structure constructed of concrete enabled a new kind of openness of spaces, a flow to the spaces and long strips of windows wrapping the building façade. Architecture and its ideals began to be characterised by extensive spaciousness, brightness and horizontality. Once concrete construction penetrated all construction, it became ordinary, mundane, even invisible. Concrete became the norm. Even now, it is still difficult to think of alternative materials to concrete when it comes to bridges or building foundations, for instance. At the same time, the dependence of the construction industry on concrete production is one of the main environmental challenges of today.
Recipe for concrete and the lightness of demolition
Concrete is made of water, cement and filler material, typically rock, gravel or sand. Cement used as a binding medium requires high temperatures, which, in turn, produce high carbon dioxide emissions. In addition, concrete structures usually include steel, in the form of mesh or other types of reinforcement. And actually, when I talk about concrete, I explicitly refer to reinforced concrete. While, on its own, concrete is highly durable against heavy weights and compression, it has a low capacity for tensile stress. The innovation to incorporate steel within a concrete cast resulted in reinforced concrete, which can be used to build bridges with small features and cover entire, shallow halls.
Reinforced concrete has also enabled the building of extensive lobbies and brightly-lit hallways in the hospital. At the moment, some of the hospital spaces are empty. This creates a situation where the lot is starting to appear as a potential place for new construction and there are plans to demolish the hospital. Work has already begun to construct the new Oulu hospital next to the hospital building.
The hospital complex is being demolished despite the fact that its concrete frame and load-bearing structure are fully intact and in good shape. The spatiality created by this frame would have the potential for a diverse set of purposes. A whole variety of lives can be imagined for it. There wouldn’t be a need to demolish it. The case of the hospital is highly characteristic of our time. Many buildings old enough to need modernization are faced with questions related to demolition. Demolition is often considered the only way to approach a building in need of modernisation that has mundane architecture, whose younger years are behind it and that may look a bit shabby.
I also find it easy to picture how the employees of the demolition company will arrive here on some chilly autumn morning. They will begin by clearing away movables: chairs, tables and light fixtures, then carry fitted units, kitchen cupboards and toilet washbasins and bowls to a trash pallet, and finally remove or break the windows. Finally, they will begin to break down partition walls. And after all that’s been done, this machine that looks like a dinosaur will arrive at the site and begin crushing the load-bearing concrete walls and the building structure. At the same time, someone will spray water with a hose to make sure the concrete dust from the demolition site will not spread to the surrounding neighbourhood. The materials will be ground to crushed gravel and heaped up onto piles.
The carbon gravel is used on motorway foundations or to construct artificial hills. The windows or fitted units may be used for building a greenhouse or furnishing a cottage. But from my perspective, I find that on a building industry scale, the recycling that currently occurs on demolition sites is done just for show. Demolishing a building produces a vast amount of materials with no purpose or a clear name after the demolition is over, and it all ends up being vaguely referred to as waste.
Concrete as an active form in a city
In those moments when I’m feeling unsure about how to approach concrete, I find myself turning to Keller Easterling, an architect and dramaturg. Easterling talks about the active forms of architecture. By active forms, she refers to factors that guide or enable design, such as building legislation, construction techniques, design tools or even the characteristics of individual building parts that affect the way the urban environment is constructed, at least indirectly. For example, the capacity of a lift to move upwards and downwards once enabled the construction of skyscrapers, which means that a lift is an active form influencing the construction of skyscrapers. Similarly, concrete has influenced what kinds of cities can be built and in which sort of environment we are living. Concrete and its characteristics contribute to how cities are formed. Concrete sets limits and creates possibilities for a city to happen. Concrete is an active agent in a city and we are living with it.