Off-site building: a new paradigm of construction

Construction uses more than half of the planet's resources, and generates the world's largest waste stream. It is part of a linear economy: a need is identified, and the building is designed, with a fairly definitive vision. The following adages still apply: "invest in stone", "build in stone"... Do we still need to think about construction as we did in the 19th century? Back then, the population was 1.5 billion, today it's 7.5 billion, and by 2050 it's expected to be over 10 billion. With growing demand and limited resources, we need to learn to be frugal and do more with less: a circular economy is an absolute necessity.

For thousands of years, people have been building their homes from materials found close to the site, in a perfectly circular economy, using stone or wood. When a building becomes too old, the materials are reused in a very virtuous way for a new construction.

After the Second World War, a lot of rebuilding had to be done, and concrete quickly became the construction material par excellence in most Western countries. The ancestral culture of stone, wood and earth became that of concrete, but the organization remained the same: site-centric!

This article is divided into several complementary sections. After an introduction, we present industrialized and off-site construction. We then present the different construction methods inherent in off-site construction. We then focus on the technological tools used, and finally briefly address the advantages and points for improvement of this construction method.

Off-site construction represents a pragmatic and relevant solution to the productivity challenge and the environmental and digital transition our sector is undergoing.

Our aim in this article is to give you a better understanding of this ongoing revolution, particularly in France. As the subject is vast and complex, the vision presented here will, of course, not be exhaustive and will not cover all the fields mobilized by this multi-disciplinary subject. Interested readers may wish to refer to the book "construction hors-site" co-authored by Beddiar et al. and published in 2021 by Dunod.