Editor’s Note: This is the first post in the Dwelling in Place series edited by Nicole Miller. You can read other posts in this series here. Selected posts from this series, including this one, will also be cross-published on Germinate: An Environmental History Review.
There is a posture every cat owner recognizes. A cat loafing on a windowsill it was never designed for, front paws tucked beneath its body, eyes tracking movement in the street below. The window was built for light and air. The sill was sized for a potted plant, a latch, or perhaps a hand resting briefly on the frame. The cat was not consulted. And yet there it is, settled with the quiet authority of a creature that has already made its decision and is not inclined to revisit it. This unremarkable scene contains, if we sit with it long enough, a significant architectural argument. The domestic window is one of the most theorized elements in the history of building, a threshold between interior and exterior, between the protected and the exposed, between the private body of the house and the public life of the street. What has been largely absent from this body of thought is the cat, the animal that has been occupying that threshold on its own terms for as long as humans have lived in houses with windows.
A Brief History of the Cat Indoors
The domestic relationship between humans and cats is ancient, but its architectural dimensions are less often examined. Cats first moved into human settlements not through invitation but through opportunity. The granaries and food stores of early agricultural communities attracted rodents, and rodents attracted cats. The cat’s presence in the built environment was, from the beginning, a consequence of the building’s function rather than a deliberate design decision. Architecture created conditions, and the cat assessed them and moved in.
For much of this history, cats occupied an ambiguous interior position. They were neither fully domestic in the sense of being confined to the interior nor fully feral. They moved between inside and outside with a freedom most domestic animals were not permitted, and that freedom was structurally enabled by the built environment. The cat door, one of the more intriguing small elements in the history of domestic architecture, appears in European buildings as early as the medieval period. It functioned as a deliberate modification of the building fabric to accommodate the cat’s need to pass through walls on its own schedule. In this case, nonhuman dwelling requirements generated an architectural response, and animal behavior reshaped the building.
The Window as Threshold
The window matters to the cat for reasons that are both practical and experiential. Positioned at the boundary of inside and outside, it offers the cat something the deep interior cannot. It provides visual access to the external environment, a stream of scent information carried in on whatever air movement the window admits, and the thermal benefit of solar gain on the sill. For an animal whose survival instincts are organized around surveillance, the monitoring of territory, prey, and threat, the window is not a decorative feature but a functional necessity. It is the point in the building from which the world can be adequately watched.
For an animal whose survival instincts are organized around surveillance, the monitoring of territory, prey, and threat, the window is not a decorative feature but a functional necessity. It is the point in the building from which the world can be adequately watched.
This instrumental relationship with the window is not only about utility in a narrow sense. Environmental psychologists and ethologists who study cat behavior in domestic settings consistently find that window access is among the most significant predictors of feline well-being.11 Cats deprived of window access show elevated stress indicators. The view from the window, the birds, the movement, the light shifting across the day, constitutes what researchers sometimes call environmental enrichment, a term that acknowledges, if somewhat clinically, that the cat has an experiential relationship with the space it inhabits. It is not merely sheltered by the building. It dwells in it as a meaningful place defined by familiar routines, recurring relationships, and opportunities for engagement.
Architecture Responds, Slowly
For most of the history of domestic architecture, the cat’s claim on the window was accommodated informally and without comment. Cats sat on sills. Owners occasionally widened sills or placed cushions on them. The building absorbed the animal’s needs without formal acknowledgment that it was doing so. This informal accommodation is itself historically significant. It suggests that the negotiation of domestic space between human and nonhuman inhabitants has been a continuous, largely undocumented feature of the history of the house.
What is more recent and more architecturally self-conscious is the emergence of purpose-built feline space as an explicit design category. The catio, a hybrid of cat and patio, is an enclosed outdoor structure attached to a building and accessed through a window or cat door. It allows cats to experience the outdoors while remaining contained. Originally a pragmatic response to concerns about free-roaming cats and their impact on bird populations, the catio has in the past decade become an established feature of domestic design culture, with dedicated architectural firms, a substantial DIY community, and a growing body of design literature.
The catio is significant not only as a product but as a conceptual shift. It represents the first moment in the long history of cat window relations in which the nonhuman inhabitants’ spatial needs are given explicit architectural form, and the building is consciously extended and modified not for human use but for feline dwelling. It is a small development in the scale of architectural history, but it marks a genuine change in the relationship between domestic design and the nonhuman beings who share domestic space.
Right: Domenicus van Tol, “Kinderen met een muizenval,” 1660-76, Wikimedia Commons.
Dwelling at the Threshold
The cat in the window is a figure with a long cultural life. It appears in Dutch interior painting as a sign of the animated, sensory richness of a well-ordered domestic scene. It recurs in urban photography as an emblem of a certain kind of city life, the neighborhood watched from above, the building as vantage point. In internet culture, the cat on the windowsill has become perhaps the most widely reproduced image of animal domesticity. Across these contexts, the cat occupies a threshold position with an ease that seems to comment on the rigidity of the boundary it inhabits. Inside and outside, human and nonhuman, owned and autonomous, the cat at the window refuses to be fully on either side.
This refusal is architecturally instructive. The domestic interior has been theorized, from Alberti to Le Corbusier to contemporary housing policy, as a space organized around human needs, human proportions, and human social life. The nonhuman inhabitants of the house, and there are always nonhuman inhabitants, appear in this tradition as accidents, nuisances, or charming exceptions. The cat on the windowsill suggests something different, that the house has always been a multispecies project, that its thresholds have always been negotiated across species lines, and that the animal sitting in the window is not a guest in human space but a co-inhabitant of a shared one.
The windowsill was not designed for the cat. The cat does not care. It has assessed the affordances of the building, the ledge, the light, the view, and made the space its own. In doing so, it has been quietly reshaping domestic architecture for centuries, one sill at a time.
Notes
- Sarah Ellis, “Environmental Enrichment: Practical Strategies for Improving Feline Welfare,” Journal of Feline Medicine and Surgery 11, no. 11 (2009): 901–912. ↩︎
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