To Demolish or Not to Demolish, That is the Question
When Shakespeare had Hamlet ponder his famous question, Renaissance architecture was in full flow, reinterpreting classical art and introducing innovative materials and building techniques. As a result, we were recently able to celebrate the 600th anniversary of the laying of the first stone in such an outstanding architectural masterpiece as the Duomo dome in Florence. Brunelleschi was a genius, but he never imagined his dome would last for so long and he gave even less thought to what would happen to it when it came to the end of its useful life. For now, it’s still standing. But what will happen when that moment comes?
As I explained several posts back, the impact of building waste is brutal: in 2016, 37% of all waste collected in Spain came from the construction sector. This is attributable to a linear model which, despite the recent boom in restoration, we still tend to perpetuate. We build new buildings, use them, and then demolish them: because they have become dilapidated over time, because they can’t be adapted for new uses, because of their energy behaviour, or simply because the land on which they stand is very valuable and it isn’t profitable to rehabilitate them.
However, this model produces more waste and more emissions than the planet can stand, and things don’t seem likely to change in the short term. We continue to build new building even though we know that almost 90% of the building stock we will need for the year 2050 is already standing, and that many of those buildings are empty and unused. Moreover, 60% of all office blocks in Europe were already unused even before the pandemic and, taking into account the current health situation and the increase in remote working, will therefore probably not be needed in the future.
So… why do we keep demolishing and building anew?
One reason is the poor energy behaviour of old buildings, which in many cases makes restoration unprofitable. But building to energy standards like Passivhaus may be counterproductive. While it’s true that it will solve the energy problem, it will probably also increase CO2 emissions. Why? Because that approach doesn’t take into account embodied carbon. Materials are often used which require a lot of energy to produce and, although operational emissions are reduced, pollution is thus increased because the building’s whole life cycle is not taken into consideration. So what should be our priority? The energy aspect? Economic viability? Emissions? Clearly we ought to consider all these things and not just focus on the economic aspect.
Demolition seems to be the most viable option for buildings in a very poor state of repair or which are not deemed suitable for the envisaged use, but there are alternatives. Adaptation studies, for example, may find compatible uses while at the same time making it possible to completely regenerate an urban area, as demonstrated in the Schieblock restoration project in Rotterdam. In cases like this, it would also be helpful for institutions to provide economic support for restoration initiatives, a strategy touted in the United Kingdom as a means of avoiding demolition.
Even so, the main problem is that of waste. In Spain, the CSCAE (Senior Council of Spanish Chartered Architects) and the Consejo General de la Arquitectura Técnica (General Council of Architectural Technology) recently published a guide aimed at improving waste management to facilitate more recycling. But we need to go further and start thinking about not generating waste in the future. For that to happen, we need to design our buildings as material banks in which all components are easily demountable and traceable with materials passports. This will allow different elements to be reused in other structures, as in Villa Welpeloo, a house built using components found via an online second-hand building materials market called Oogstkaart.
But we still have a long way to go in this direction, and perhaps we should now start thinking about another vital issue: “Linear or circular?”.
Text translated by Andrew V.Taylor.