What Rooms Do to People

An architect designing a hospital asks about bed count and budget. What they rarely ask: How much daylight does a patient need to recover faster?

The answer exists. Joarder and Price published it in 2013. 100 lux more daylight in a room shortens the hospital stay by an average of 7.3 hours. That’s data from a controlled study.

But that number sits in a journal no architect reads. It’s one of thousands. And on its own it helps nobody because it only covers a single variable. A patient room has light, temperature, acoustics, materials, view, spatial proportions. Each of them affects the patient. None of them works in isolation.

The research on all of this exists. It just has never been brought together for practice.

The Numbers

Patients in rooms with a view of trees need less pain medication than patients looking at a wall. Roger Ulrich showed this in 1984. The study has been replicated hundreds of times since.

Biophilic design increases cognitive performance by 13.9 percent. Terrapin Bright Green calculated that in 2023. Biophilic means: plants, wood, water and natural patterns in the room. Things the human brain knows from evolution and responds to positively.

Employees without a window seat sleep 46 minutes less per night than their colleagues by the window. The Human Spaces study measured this. 46 minutes less sleep because someone drew the floor plan so their desk ended up in the middle.

If the room temperature is too cool, performance drops by 4 percent. Too warm: minus 6 percent. The range in which a person can work productively is narrow.

Why This Doesn’t Reach Practice

The findings are sorted by discipline, not by use case. Lighting research, acoustics, indoor climate: each topic has its own journals. Anyone planning an actual building would need to work through hundreds of publications to find all relevant studies for their situation.

Nobody does that. So buildings get designed without knowing what they do to the people inside.

The Principle

I’ve structured the research so that you get a reliable answer for a specific situation.

You describe the context: what kind of building, who uses it, for what purpose. Then the stimulus: which element of the room you want to look at. The system shows which effect is supported, how strong it is and which study it comes from.

A child responds differently to ceiling height than an adult. A dementia patient responds differently to noise than a healthy visitor. An office worker has different needs than a hotel guest. The answer always depends on context.

Hospital

Daylight shortens the length of stay. Nature views reduce the need for pain medication. Add natural materials that lower cortisol levels and quieter acoustics that improve sleep.

Most of this costs nothing extra. Whether a patient looks out the window at trees or at a fire wall is determined by the floor plan.

Office

90 percent of a company’s operating costs are personnel costs. Rent and energy together make up 10 percent. A small improvement in the work environment delivers more than the entire energy savings of an ecologically optimized building.

Ecological building matters. But whether the room temperature is right, whether enough daylight comes in, whether the acoustics are bearable, that determines whether people are productive. And these decisions are almost always made based on experience or on taste. Rarely based on effect.

The Question

There is no general recommendation for “the good building.” Biophilic design increases cognitive performance by 13.9 percent on average. But in a classroom for children with ADHD that means something different than in a hotel lobby.

The effect is always specific. The precision is not in the average values from the studies. It’s in the context. What kind of room. Who uses it. What they do there.