The Air We Build 

(Scent) On a winter morning at Therme Vals in Switzerland, slipping into one of Peter Zumthor’s heated pools, it’s the air that takes center stage. Against a backdrop of stone and light, warmth rises, carrying minerals and the faint sweetness of alpine herbs. These are fragrances that soothe the body, slow the pulse, and focus the mind. Here, the air is composed as deliberately as the Vals quartzite that frames the spa’s architecture.

Steps descend into a cool bath strewn with petals. The walls exhale aromas that recall medieval flower baths once scattered with chamomile and rosemary. Moisture, temperature, and light entwine into a total sensory construction. Zumthor wrote that atmosphere begins when a building touches emotion; at Vals, emotion moves through air.

Architecture has long been approached and deconstructed primarily through sight—proportion, material, illumination—yet one of its most persuasive materials is invisible. Scent travels directly to the brain’s emotional center, reaching the limbic system long before logic stirs.

The Proust Effect
This so-called Proust Effect—named for the novelist whose childhood rushed back with the smell of a tea-soaked madeleine—reveals the sense of smell as a true mnemonic. Neuroscientific research repeatedly shows that fragrance-evoked memories carry greater vividness and emotional charge than visual ones.

Scent connects physical space to memory, immediately and vividly: the ozone of polished concrete after rain or the warm trace of sandalwood in a dimly lit bar can summon entire histories of feeling. This intimacy grants scent enormous architectural potency. It lends familiarity to the new, warmth to the austere, and distinction to the globalized. The built world exhales, and we breathe it back in.

Air as Material
Today, a renewed embrace of fragrance as a tool for shaping atmosphere sees the same sensibility enhance contemporary design. What once belonged to priests and perfumers has entered the vocabulary of a growing niche of spatial fragrance designers.

Across continents, a new generation of scent designers is treating air as an artist would a canvas. Founded in Melbourne and operating from New York to Tokyo, Air Aroma composes fragrance systems engineered for emotion, diffused through HVAC networks. The company’s perfumers and branding specialists collaborate on scents that narrate identity and mood, which are designed to linger without overwhelming. In Tokyo, AT-AROMA builds its “Aroma Space” projects with unblended natural oils, mapping fragrance to light, texture, and form. Their intangible installations—infusing through department stores, spas, and company headquarters across and beyond Japan—approach air as an act of atmosphere.

Research backs this, showing a crafted scent increases brand recall by 15% and encourages longer engagement in retail environments. The hospitality industry was an early adopter. Luxury hotels have long partnered with luminaries of fragrance design to create signature scents for their properties—Aman with Jacques Chabert, Standard Hotels with Air Aroma, and EDITION Hotels with Le Labo, to name a few.

Beyond hospitality’s upper echelons, residential and workplace scenting now command rising attention. The global scenting market, valued at over US$11 billion in 2024, is expanding by more than 7% each year.

In addition to offices and homes, spaces of travel and transit lend themselves particularly well to scents of comfort and calm. Air France’s premium lounges feature AF001, a signature scent crafted to evoke relaxation. Kempegowda International Airport in Bengaluru has introduced “Dancing Bamboo,” a calming fragrance developed with Mumbai-based aroma studio Aéromé to enhance passenger comfort in key terminal areas. In the automotive sector, Mercedes-Benz offers an “active perfuming system” in their S-Class sedans, allowing owners to customize the car’s scent through an in-built fragrance atomizer.

Looking ahead at the leading edge of spatial fragrance, emerging trends in AI are supercharging the personalization of spatial scent, transforming how environments engage our individual sensory profiles. Innovative systems like the Institute of Science Tokyo’s “Odor Generative Diffusion” model uses mass spectrometry profiles and scent descriptors to autonomously create custom fragrance blends.

As functional fragrances flourish into a multi‑billion‑dollar industry, architecture—along with the cultural and commercial experiences it frames—is rediscovering what ritual and craft once knew instinctively: space extends beyond the physical. It breathes, resonates, and drifts through air, engaging in dialogue with light, sound, and scent. In this interplay of senses, invisible architecture reveals its depth, guiding us through atmospheres that stir us as much through sensory presence as through perceptual form.