What Buildings Cost 1/3: What Does It Cost?

In 2012 a research team at the Bavarian State Office for Health ran an experiment in six German schools (Twardella et al., 2012, Indoor Air). In 20 classrooms they changed the air quality, once good at 1,045 ppm CO2, once poor at 2,115 ppm. Then they tested the children with a standardized concentration test.

The children with poor air were not more tired and not slower, but the error rate rose significantly. Neither the children nor their teachers noticed.

2,115 ppm CO2 is not an extreme value. In many German classrooms without mechanical ventilation the levels are higher. Children spend a large part of their day in these rooms and they have no way to assess or change the conditions.

At the Charité in Berlin doctors and the architecture firm GRAFT redesigned two intensive care rooms in 2013. They installed lighting that simulates the day-night rhythm, dampened the noise and hid the visible medical equipment behind wall panels. The delirium rate in these rooms was 46 percent. In the standard rooms 76 percent (Spies et al., 2024, Critical Care Medicine). ICU delirium extends hospital stays and costs five-figure amounts per case.

Joseph Allen measured in the COGfx study how air in office buildings affects thinking (Allen et al., 2016, Environmental Health Perspectives). In well-ventilated buildings the cognitive test scores were twice as high as in conventionally ventilated ones. Crisis response was 131 percent better, strategic thinking 288 percent.

The findings are neither new nor isolated. Roger Ulrich showed in 1984 that hospital patients with a view of trees need less pain medication and are discharged sooner (Ulrich, 1984, Science). The study has been replicated hundreds of times. The WHO estimates that 13 percent of asthma in European children can be attributed to damp housing (Braubach et al., 2011, WHO Europe). The evidence spans decades and hundreds of studies.

This is why, drawing on my experience with AI-based analysis in marketing and retail, I developed a system that evaluates the research on these effects by building type and user group. It was a fairly big stretch, but thanks to artificial intelligence and the corresponding coding tools the path was less rocky than expected. The data was extensive and, because scientific, also very consistent and easy to work with. There is no shortage of scientific research or of ways to translate it for practice. It just doesn’t reach the planning or the construction. Research is organized by discipline. Anyone planning a school building would have to work through acoustics, lighting research, indoor climate and materials research in parallel. Each field has its own contexts and logics. In practice hardly anyone does that.

The decisions that determine room quality are made in the floor plan and the building services. Many of them don’t cost anything extra. Whether a patient looks out the window onto trees or onto a firewall is a question of planning. These decisions are not based on the available data to the extent they should be. Planners decide anyway, on whatever basis.