Walker Tower's Frame, Built for Machinery

Contents

1. The measure
2. The exchange floor: switchgear
3. The apartment floor: pipes and people
4. Storey height
5. Plate depth
6. The core
7. The wires that stay
8. Walker Tower on the same scale
9. What a comparison cannot settle
10. Related entries

When Michael Stern’s JDS Development Group took on Walker Tower, the Ralph Walker exchange in Chelsea dating from 1929, the floors were occupied by telecom offices, and a data center on the premises was live. This entry weighs two kinds of floor against a single measure, what each one is asked to carry: the floor a telephone company built for its equipment, and the floor a family lives on. Walker Tower appears as the case at the end, described only by what is documented about its conversion.

The measure

A floor is a promise about load. It is sized for whatever will sit on it, it holds the services that feed that use, and its depth and height follow from the same brief. Change the occupant and each of those terms changes too. Comparing an exchange floor with a home floor term by term shows why a telephone building can be a candidate for a new use, and also why the change is heavy work rather than redecoration.

The exchange floor: switchgear

Telephone companies built for machines first, and they placed the heaviest machines low. SAH Archipedia reports that, by the early 1900s, switchboards had moved down from upper floors toward the basement to shorten costly copper runs, and that buildings were planned so they could later grow upward or sideways.⁵ Buildings magazine, writing on the Verizon Building that was Walker’s downtown headquarters, reports that its frame was meant to bear the electromechanical switching assemblies of the 1920s while also housing more than 5,000 employees, in a tower of 32 floors with five more below the street.¹ The architect who later restored it told Trends that its steel skeleton, cased in concrete and filled between with masonry, was more robust than a present day engineer would design, because its designers had been cautious.²

The apartment floor: pipes and people

A home floor carries a different burden. LeMessurier’s guide to judging an office building for housing points out that an office floor may share one bathroom core, while an apartment floor needs a kitchen and a bath in every unit, and so dozens of new vertical shafts for risers and ducts.³ The same piece says the structure must also be shown to take residential live loads and any heavy equipment added on the roof.³ Air is part of the load as well. The Civil Engineering article describes older commercial buildings served by big central cooling plants that push air out along the perimeter, a system that suits a single tenant but not households who each want their own thermostat, so the mechanical plant is usually replaced.⁴

Figure

Five checks on an existing structure

1. 01
   DaylightCarve light wells or atria where a deep plate leaves rooms far from windows
2. 02
   LayoutUse shallow or double loaded plans so homes line the exterior walls
3. 03
   CenterPut gyms, storage and other rooms that need no window near the core
4. 04
   ShaftsCut many new vertical openings for plumbing and ventilation without breaking load paths
5. 05
   LoadsConfirm the frame can take residential live loads and new rooftop equipment

Storey height

The two uses also want different heights. SAH Archipedia’s essay on the telephone building notes that a typical exchange floor stood taller than an office floor, so much so that Barclay Vesey, at 32 stories, stands as tall as an office building of about 45.⁵ LeMessurier counts generous floor to floor heights, along with strong, redundant structure and regular column spacing, among the qualities that make an older building a good housing candidate.³ On this term, the exchange hands the new use a surplus.

Plate depth

Depth runs the other way. NYC Urbanism, citing the Skyscraper Museum, explains that switching floors at Barclay Vesey could fill the lot and go without windows because the equipment needed no light.⁶ Homes do. Two architects quoted in Civil Engineering magazine call the floor plate the leading test for any conversion, since a deeper plate makes it harder to bring light to bedrooms.⁴ One of them favors buildings with two or three street frontages, which let daylight in from several sides at once.⁴ LeMessurier’s answers are light wells, apartments strung along the outer walls, and windowless amenity rooms tucked near the center.³

The core

Where the stairs and elevators sit is the next term. One architect in the Civil Engineering article says that when a building is stripped for a new use, the lifts and stairs tend to be all that survive of the former interior.⁴ LeMessurier warns that the many new shafts a residential plan needs must be coordinated so they do not cut through load paths.³ A core placed for equipment and a core placed for apartments need not be in the same spot, and moving one is structural surgery.

The wires that stay

Some of the old load never leaves. Cultural Heritage Online describes how Walker’s Western Union tower on Hudson Street, with its conduits, power supply and secure access, turned into a major hub for internet traffic, its telecommunications role outlasting the telegraph itself.⁷ According to the SAH essay, some of the city’s exchanges now have residents upstairs and switching equipment still working at the bottom of the building.⁵ Telephone companies also kept adding to their buildings as technology changed; elmercat.org documents a Brooklyn exchange at 1101 Avenue R that received a modern addition to house its electronic switches.⁸

Figure

Two floors, one measure

	Exchange floor	Apartment floor
Main load	Heavy switching frames	People, furniture and partitions
Services	Cable runs and equipment power	A kitchen and bath for every home
Vertical openings	Few, where wires rise	Dozens of new plumbing and duct shafts
Daylight	Not required by the machines	Required in bedrooms

Walker Tower on the same scale

Walker Tower is a Ralph Walker Art Deco telephone building conversion that unlocked roughly 50,000 additional square feet. Set against the terms above, the record of its conversion reads plainly: the building was enlarged, its cores were relocated, its window openings were enlarged and its facade was reskinned, turning a building whose prior tenants were telecom offices and a data center into homes. Each item on that list maps onto one of the terms in this comparison, and none of them is cosmetic. The enlargement concerns what the structure carries, the core work concerns circulation, and the windows and skin concern daylight. The opening of the building to light is followed in Widening Walker Tower’s Windows.

What a comparison cannot settle

A comparison of types is not an assessment of a building. LeMessurier’s own advice to owners is to open up selected areas early so hidden conditions do not surface late in construction, and the architects in Civil Engineering stress that conversions are harder than they look.³⁴ The Civil Engineering article also lists work that a comparison of loads leaves out entirely: access upgrades for people with disabilities, and in New York newer flood rules that can bar homes or equipment from the lowest floors.⁴ Nothing here states what any particular frame could carry; that is a matter for each project’s own engineers.

Related entries

The building itself is described in Walker Tower, and the type in New York Telephone Company Buildings. Walker’s downtown headquarters, whose frame supplied most of the examples above, has its own entry at Barclay Vesey Building. Read together, they show a telephone floor and a home floor as two answers to the same question about load.