The future of concrete and steel for residential construction? The helm must change!

Martijn Broekman - developer/project manager at Bo-Ex housing corporation

From the Paris Climate Agreement in 2015, we in the Netherlands set the goal of having a climate-neutral and circular built environment by 2050. These goals have to do with environmental impact and contribute to limiting global warming beyond +1.5°C. CO2 budgets have been set at the national level for this purpose; the construction sector has been "allocated" a portion of this to use until 2050.

Is this budget sufficient? In housing construction, many stakeholders have been working on the energy transition for years. Homes are being renovated every day, and new construction is subject to increasingly stringent requirements. However, climate neutrality is all about CO2 emissions from both the manufacturing process and the use phase. Currently, the focus is mainly on the use phase, less on the road leading up to it.

As a sector, we are unfortunately already well behind the 2050 targets. In April of this year, W/E consultants indicated that the current emissions (CO2 emissions) of the homes being built now are almost twice as high as our "CO2 budget" until 2030. Twice as high, that means we're not even close. And after 2030, the maximum emissions are even lower. 

With the "Climate and Energy Outlook 2022," the government also already admitted that we are behind on targets. It is now also becoming clear how construction is contributing to this. With the current types of houses being built and the targets that are in place for 2030, we will already be through the CO2 budget in a few years. The homes we are designing now are the homes that won't be delivered until 2025. That all the homes we design today will be emission-free is a pipe dream. 

In the circular field, I see another at least as big a challenge. Although a lot has changed in this area in the past 10 years, the task has not diminished. How do we ensure that all buildings will soon be circular? And these tasks also touch and influence each other, as the environmental impact of heat pumps was recently called into question. A solution may be smart from an energy point of view, but not from an environmental point of view. 

Fortunately, more and more parties are aware of the challenge and task we face and are committed to this. The manifesto 'Building within the limits of our planet' has now been signed by numerous parties active in the construction sector. Consulting firms as well as contractors and manufacturers. More and more concept homes are also being made with a high proportion of renewable materials, demountable and at lower CO2 emissions in both the manufacturing process and use. But in the list of signatories, I don't see any concrete or steel suppliers. Why is that? Concrete and steel are products with a high environmental impact. Despite the beautiful qualities both materials have, it takes primary materials and a lot of energy to make these products. Given the goals, there is a lot of ground to be gained here. But I see few solutions from the suppliers. Only reusing what is already there covers only a small part of the need. Last week it was announced that the Concrete Accord will be awarded a grant from the National Growth Fund to enable the development of sustainable concrete. I hope this leads to solutions that contribute to the goals and the concrete sector will not fall behind. Otherwise, I fear for the survival of this sector in (residential) construction and the future of this appealing magazine.