Definition
A transition space is an ephemerally occupied one situated between better defined and structured places as in the feature image: a footbridge crossing from “mainland” to an artificial island surrounded by a shallow ditch fed with water by the nearby river.
That ephemerality is due to the fact that the space facilitates movement from here to there … In this case, the footbridge connects a parking complex to the island occupied by a large outdoor dancing floor covered with a shed roof; it does also serve as reference point for people waiting for others to join them, adding a social dimension to the strictly instrumental function of crossing over the ditch.
Context and situation is what allows us to distinguish between types of transition spaces and to characterize their spatial poetics. We shall rely, again, on a body of images from a current work in progress in order to analyze transition spaces as notion, and as experience.
Entering as transition space experience
Going from outdoors to indoors is an ordinary experience of perceptual saliency involving clear change in environmental and territorial conditions, and in instrumental and social involvement.
In the case of a private residence, the process of entering takes us through three doorways and three degrees of control of access from least to most evident: the opening in the sidewalk bordering low fence, the lightbulb framed opening at the head of the stairs leading to the front porch and finally the entry door to the residence itself … at each limit the visitor can slow or stop to be identified and/or to be called out to.
If the front porch is the better defined space we go through before entering, it has taken the form of a semi private place to go to given the outdoor love seat next to the curtained window. The lack of the usual porch light, however made up for by the decorative lighting, seems to indicate that no one is home, or that no one is expected!
Situationally speaking this is a virtual three-persons setting: the incoming person, the person on the love seat and the person at the window checking on the situation from behind the curtain … we could well imagine a fourth one coming down the side stairs from the upper floor! (See image below)

In the case of an institutional residence, the process of entering is mediated by a wooden uniformed valet, straight out of the Nutcracker ballet suite, whose figure stands at the intersection, visually at least, of the entryway and the building air lock (we are in winter), with its chic tied curtain and bench seat. We surmise that the exterior door of the airlock to be open to the public, but that access to the interior one is limited to resident with their key or to the public upon identifying themselves on an intercom system.
All these details are important, as is the generous outdoor lighting provided by the decorative lights, the outdoor soffit lights and the free standing lamp post.
Already seen at a distance from the airlock is the community board with its movable white letters and a corner of the reception desk … these are sure signs of an institutional setting. As a member of the public, these standard items of an institutional semi public entrance make one feel informed and oriented in what is by definition a controled access and secure environment.
No elevated private front porch here: the on grade universally accessible entrance and all the lighting and decoration contribute to communicate these essential qualities (standardization, control and security) that define, color and inform the process and experience of entering an institutional residential setting. (See image below)

Exiting as transition space experience
Whether through a transitional airlock, or through direct access to the outdoor, going from inside to outside involves a moment of re-orientation to the weather, to the social situation and to the space one is stepping into or is about to do so.
One major difference in the process is whether one is alone or in company. While standing alone in the airlock of my apartment building, I am struck by the reflection, on the plate glass doorway in front of me, of the ceiling light fixture of the lobby behind me … more curious still is the alignment of my position with the entry doorway of the apartment building across the street brought into sharp focus by my shadow.
This moment of position awareness in space brings about an awareness of the re-orientation process upon exiting. The anticipated choice of direction to take once at the sidewalk brings forth a quick mental review of things I may have forgotten to check or bring along upon leaving the apartment, etc.
Doing this at this point in space allows me to return in time to my apartment to fetch or check these items. (See image below)

Once outside a village curiosity shop, there is no walkway to lead one to the sidewalk but a paved yard which gives plenty of room and time for a small group to discuss their purchase or a possible purchase, their next stop in the village or a return to make that purchase, etc., in other words to put to good use the time to cross this physical and social transition space from inside the shop to the street.
Sometimes a car may be parked in the yard while a client loads a large item adding to the entry-exit yard the function of loading area that a pedestrian walkway would not have been able to handle.
Note the folding advertising sign at the sidewalk to indicate the presence of the shop a distance back from the street … a sign that will come down eventually when the commercial building next door takes over the Curio Shop for a parking lot extension. (See image below)

The stair landing as transition space experience
A classic situation that gains from having a window to the outside. From being a space to accommodate a change of direction going up or down, a landing with a window and of generous dimensions, becomes a space from which to savor a building construction detail or a city corner while keeping company to a sculpture.
Strategically located at certain levels of ascending, or descending, the treatment of these landings will provide vignettes experiences of parts of a building that cannot be seen from anywhere else.
In the case of a classically designed community center, the landing of this richly crafted wooden stairs harbors a tropical plant and a view of details of the front porch of the building: classic columns, copper sheet roofing, wood soffit moldings, etc.
From the landing window one can see a balcony extending from the next floor up, over part of the front porch.
The window of the landing invites one to pay attention to these details of the building classic tectonics from a different perspective, in terms of time and position, than the usual one from the street level only. (See image below)

In the case of the grand stair-ramp of a fine arts museum, the view is almost a 360 degree one as it covers not only the street but also the opening to the sky over the glass roof covering the museum lobby.
At the center of this generous visual arc, and off the landing circulation pattern, the museum chose to place a sculpture in the genre of a classic Greek nude in wood, painted blue.
Enough to stop and take in the view … in good company!
With a bit of care one can discover, in that panoramic view, an interesting palette of architectural styles from the neo-classic original museum building off to the left of the image, to a neo-romanesque church now a performing music centre connected to the museum, and a few non-descript eclectic downtown golden era and contemporary apartment and condomunium buildings.
This landing is not only a transition space from floor to floor of the museum but its generous windows allow visitors to catch a glimpse of some of the collection as they look up from across the street and contemplate entering the museum via its monumental foyer … in an interesting inside-outside visual conversation. (See image below)

Discussion
“I can take any empty space and call it a bare stage.” Brook, P. The empty space.
Brook’s definition of an empty space as theatrical setting and/or catalyst for the dramatic moment/action has shaped my approach to environmental design and my appreciation for spaces offering opportunity for the realization of significant human moments … and place making.
My choice of images as iconic reference for the discussion of the poetics of transition spaces which, more often than not, is indeed of “empty spaces” that draw their evocative poetic value by being in between.
The fact that half of the images are night scenes adds a bit of mystery as to what is on the other side of the “in between” space.
The empty footbridge, however empty, is the only access to an outdoor dance floor, channeling attention, anticipation and purposeful movement toward and away from the island dance floor.
The house front porch and the residential buildings airlocks are basically empty spaces but for their territorial and social context, their furnishing and communication systems, creating virtual and visual mini dramas.
Both landings are, as they legally and instrumentally must be, empty but for an object placed in them to break the movement sufficiently for the climbers to slow down and become aware of the multiple “in between” perspectives available to them.
Finally, the extra width of “empty space” between sidewalk and building provides all that is necessary for the installation of the quintessential urbane “encounter zone” of coffee outdoor terraces, with room for impromptu merchandise display, etc. … for discrete street theatre! (See image below)

Credit all images Maurice Amiel
Pertinent bibliography:
Mugerauer, R. “Toward an Architectural vocabulary: The Porch as a Between”, in Seamon, D. (ed.) DWELLING, SEEING, AND DESIGNING, (p103-128), SUNY Press, 1993.