Slab, corridorSlab, double-loaded
The Edge
GBD Architects & Holst Architecture | Portland, OR, USA | 2004
Image of The Edge
West facade along 15th street, screened parking structure with 7-story residential block above.

ProjectThe Edge
ArchitectGBD Architects & Holst Architecture
CityPortland, OR
CountryUSA
Address805 NW 14th Ave.
Building TypeSlab, double-loaded
Number of Dwellings125
Date Built2004
Dwelling Types1 BR; lofts
No. Floors11
Section Typeflats
Exterior Finish
Materials
concrete, glass metal curtain wall, perforated steel panels,
Construction Typeconcrete frame
Ancillary Servicesparking garage & retail store

The Pearl District in Portland, Oregon is a new community being built in a former industrial, warehousing and railroad loading and maintenance area immediately north of the city center. Although this district had been used only marginally for many years, major historic buildings remained, others had been converted to artists’ lofts, and the district was known for its art galleries. “The Pearl” had been the focus of various planning studies since the 1980’s and, in 2001; “The Pearl District Development Plan” was approved by the City Council. This plan outlined a broad program to transform the Pearl into a vibrant mixed-use pedestrian community with new housing, public squares and gardens, a new surface transportation system called the Portland Streetcar, a program of historic preservation as well as code adjustments and tax incentives to promote new construction and the conversion of old buildings into loft and commercial uses.

The Edge is a mixed-use building that was built in 2004 in a zone of several large 6-8-story warehouses along the western boundary of The Pearl district alongside a freeway that was part of the Portland ring road system. These buildings were typically a block in size and together formed a tall, dense boundary between the Pearl district to the east and the beautiful old residential district west of the freeway.

The problem of noise and a close visual proximity to the freeway was a major obstacle to either converting or designing a building along a 6-lane interstate highway that is partially elevated where is passes just a few feet from these buildings. This wall of buildings next to the freeway helps block traffic noise from migrating into the Pearl streets to the east. Concrete construction and triple glazing has been used to help to control interior noise levels (as long as the windows are not opened). But, little can be done about the constant ambient sound generated by a busy highway. The eastern view from the opposite side of the building is the dynamic scene of a new community under construction with views of bridges and even snow-capped Mt. Hood in the distance. The view to the west is of the tree-lined streets of a lovely old residential neighborhood that slopes gradually up into the west hills. The foreground of this scene, however, is a relentless, concrete-lined, river of vehicles.

The Edge apparently takes its name from this position at the edge of the Pearl District, but also from its location as part of this wall of warehouses at the edge of the freeway. The raison d’être of the design was to cover a city block with a 4-story high base that contains a parking garage and an REI retail store. The residences are built on top of this in a 7-story, double-loaded slab that has a footprint about 2/3 of the size of the block. The combined height of the two elements is 11 floors thus aligning with the heights of adjacent older buildings. The massing concept is clear in the exterior views of the building and is consistently developed in the plans, sections and details. The slab is positioned on the east side of the block, away from the freeway, to give some protection from the view and noise of the freeway. The top level of the garage is an open parking deck that is partially landscaped with plant materials and a metal trellis that softens the view from the dwellings along this side of the building. Aligning the slab with the eastern edge of the block has the advantage of gaining some setback from the freeway.

At first glance The Edge looks like a conventional double-loaded slab. The exteriors are treated differently reflecting different orientation and site conditions. The east façade is treated as a flush, glass curtain wall that is the vertical extension of the storefront glazing of the retail store on the lower levels that wraps the ends of the building the depth of the living spaces within. The west façade is treated as an infill frame with a continuous shallow balcony at the bottom level and integral balconies above and a zone of deeper terraces on the top floor. This façade also wraps the ends the depth of the interior open spaces. Smaller individual windows are used in the end elevations to express the position of service spaces along the corridor, however, it is not clear that the end apartments do not merely register the organization of the plan.

The plan reveals subtle differences between The Edge and a typical double-loaded slab. First, the building is very wide; it doesn’t have the proportions of a typical slab-type building. It is more than twice as wide as Mies van der Rohe’s Lafayette Park slabs that might be considered a benchmark for a double-loaded precedent. This means that dwellings are very deep so that day lighting of the interior areas is a problem in a 1-story high room. This also means that “loft” dwelling types are virtually required because enclosing these deep interior spaces would leave them without natural light and ventilation. The extreme depth is somewhat alleviated by putting the kitchens in the zone of living spaces and this move helps integrate the service and living areas and gives the impression of one large room.

The second difference is a result of the narrow structural bay. Several different dwelling types are used in the Edge, but most are built in one structural bay. This results in a long, narrow space, with floor to ceiling glass at one end—but without the 2-story volume needed to let daylight penetrate into the deep interior. Comparing another benchmark here, the apartments in Le Corbusier’s Marseilles unite d’habitation are about 12’ wide as compared to the 18’ in The Edge. Larger dwellings are used at the corners to take advantage of the increased exterior walls. Occupying the ends by wrapping the glass around the corner reduces the problem of the blank end facades typical to many double-loaded slabs.

In spite of the problems with freeway noise and view, and the minimal landscaping of the roof of the parking deck, and even of the lack of continuity of the wall idea of the old buildings along the freeway, caused by the setback, the west façade is a remarkable Rationalist invention. Using a narrow structural bay (and presumably a flat slab) results in an exterior frame where column and spandrel are about the same dimensions so that the whole upper façade is treated as a layered, three-dimensional grid. While there are balconies only along the lower level, the slight set-back of the infill panel implies another spatial layer suggesting a balcony zone that gets deeper at the top floor where there are larger apartments and actual terraces. Full height doors and integral balustrades in the infill panels also suggest balcony uses. The detached repetitive grid of the upper floors of the west façade seems to float above the surface of the parking deck.

Various proposals have been made to relocate the freeway where it passes the west edge of the Pearl. Part of the freeway is elevated now because of the need to ramp up to the Freemont Bridge. Some east/west streets pass beneath the freeway now in some of these elevated sections, as does The Portland StreetCar. But the noise is still debilitating even underneath the freeway. Tunneling the freeway would allow easy, at grade connections between the neighborhoods to the west and would greatly enhance the livability of buildings like The Edge that would now be free of highway noise, would have a direct pedestrian connection with and views of these neighborhoods and would be missing a foreground view of a 6-lane interstate highway.

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