A D D I T I O N A L   I N F O
P A R T   I V


The Landmarks Preservation Commission
Building renovation I - General
Building renovation II - The Sony Building A.D. 1992
Building renovation III - City of renovation
Telecommunications and companies
Green considerations
Skyscrapers and nature
New York City and earthquakes

An article on living in a Manhattan high-rise

Even before the forming of any city-controlled and -led body, there had been early work on preservation by private organizations and citizen groups, with also a number of preservation victories to show for their efforts -- although a great majority of the condemned buildings in post-war NYC went without any organized protest.

Perhaps the most notable of these pre-Commission civic group victories were the salvation of the Carnegie Hall (William B. Tuthill, 1891) in 1956 and the Dakota Apartments (Henry J. Hardenbergh, 1882) in 1961 (landmarked in 1970). Although it must be noted that the Carnegie Hall survived the replacement by a 44-storey gold-coloured high-rise slab (Pomerance & Breines) mostly because of the developer's funding problems...

After decades of "vintage" building replacements, the last straw was the tearing down of the old Pennsylvania Station (McKim, Mead & White, 1910) (link) in 1963-1966 and the Renaissance château of the Brokaw family at Fifth Ave./E 79th St. in 1965, when the New York Landmarks Preservation Commission was formed and the Landmark Preservation Law passed to prevent the destruction of old buildings of historic significance. (The architect firm of I. M. Pei, which was involved in a replacement plan for the Penn Station, a 32-storey giant mart called the Palace of Progress, the world's largest building, had in 1956 also made a proposition for another NYC preservation hot potato, the Grand Central tower. The Grand Central development proposition, by the way, led to the compiling of a list of New York City's historic buildings by the Municipal Art Society. In 1957 the list of buildings recommended for protection from further development was published -- along with a disclaimer that the Society does not take responsibility for the listed properties losing their resale value...)

The commission consists of eleven commissioners, selected by the mayor and serving for three years, helped by staff personnel and volunteers. The appearances of buildings (or their selected portions, like interiors) with a granted landmark status are controlled by the commission, so that any requested changes by the owner are subject to Commission's review.

Demolition of a landmark is prohibited, unless the owner can present financial reasons for it -- even then the city will first try to find a more co-operative buyer for the building, offer tax abatements, or enable the selling of property's air rights. The landmark status also requires the owner to keep the property in good shape and safe to operate. In return for these demands, the owner will be presented tax abatements and advantageous loan arrangements, as well as other benefits.

(Even the designated status is not always enough to prevent the owners from demolishing parts of a landmark. In 2002, the Amster Yard, a grouping of 1966 landmarked buildings around a landscaped courtyard on 49th Street at Second Avenue, was mostly demolished without a review or acceptance from the Commission. In lieu of the approved renovation of the existing buildings, most of the buildings as well as the whole courtyard were demolished and dug up from the way of an underground auditorium and educational facilities within the rebuilt replica houses. Although the regulations allow the city to fine the owner up to the whole value of a destroyed landmark, it is uncertain under what circumstances such measures would be taken.)

Five years after its forming, the commission, still uncertain about its power against the investors and large companies, failed to prevent the demolition of the Singer Building from the way of new office space construction. The commission, however, had gradually increased its power through media management and gaining of political support for its aims. Now the commission has consolidated its authority and has also spread its influence into preserving important public interiors, the interior of the Public Library being the first one in 1973.

Despite its increased influence and power, the Commission has been at times surprisingly slow in enforcing a landmark status on, at least in the Great Public's eyes, notable structures. Although a landmark must be at least 30 years old, the designation has often taken considerably longer. The Chrysler Building (landmarked in 1978), Empire State Building (1981) and the Rockefeller Center (1985) have been such high-rise examples.

In addition to the individual and interior landmarking, the Commission also designates so-called Historic Districts in which a specified area ranging from a few buildings to whole neighbourhoods (like Greenwich Village) is declared a landmark, with similar effects on property owners. The designation, and subsequently a "forced-on" orientation to preservation has stimulated renovation of these old, previously overlooked buildings.

Another large-scale designation type is the Scenic Landmark designation, in which an area of scenic and natural importance is preserved from changes. Central Park is the most notable, or at least the largest, of these.

As of May 1997, after 32 operating years of the Commission, there were 964 individual landmarks, 98 interior landmarks, 69 historic districts and 9 scenic landmarks, mostly in Manhattan.

The Landmarks Preservation Commission web site

Renovation of skyscrapers, both old and relatively new, is an activity that is constantly employing building firms. Building renovation takes place because of a need to preserve a building as a landmark of its era and style, because of a need for new interior arrangements or uses for the building or because of new structural demands within the building. The result may also be a combination of these. Well, tearing down a building can also be seen as a kind of "renovation", albeit a radical one...

Renovating of an old building is usually more economical than tearing it down and building a new one from scratch, unless there is a need for larger individual floors in the building or the land owner is determined to get more out of the plot than carry on with that old "zoning regulations ziggurat"...

Although old high-rise buildings have their exteriors merely cleaned and restored, the interiors are practically always modernized (unless the interiors are a designated landmark), and usually the only interiors left to the original state (or restored to the old-time splendour) are the entrance lobbies or other lavish interior spaces within the building.

The most arduous single undertaking in renovating old skyscraper interiors is the addition of air-conditioning ducts, because buildings built before 1950 usually have no provision for them. To accommodate ducting, holes are cut in the floors, through which the vertical ducts are then run. Other service additions and improvements include new plumbing and electric, telephone and computer network cables.

The older buildings of the 1930s are usually made of strong steel with a very rigid frame, so they can withstand the wind pressure well, swaying only a minimal amount -- the Empire State Building sways only about five millimeters at the height of the 85th floor. Skyscrapers built in 1960-1970 are built with less massive frames -- to save costs -- and are thus the ones usually in need of internal supporting for rigidity, because wind can cause the building to sway considerably (the World Trade Center towers are designed to sway 2.7 m in strong wind, although usually a maximum arc of approx. 2 meters is encountered). This in itself isn't dangerous, but certainly not very pleasant either.

NYC24 article

Old buildings can also be retrofitted with a more modern facade panelling to extend the lifespan of the building. The problems with fastening of facade panels to the frame can also cause problems in modern skyscrapers. The case of the Amoco Building (1973) in Chicago is one such, when a relatively new skyscraper facade had to be re-clad in a new material because of falling-off panels.

The amount of windows on the outer walls of glass curtain -walled buildings (well, there isn't much other than windows, really...) lays demands on the thermal economy of the window type used. Large window areas can cause considerable loss of heat from the building, and consequently increase the demand for heating. The modern, double pane, vacuum insulated windows used in the newer skyscrapers are rather efficient, but the older buildings - like the United Nations Secretariat -- have windows that are not very impressive as insulating building members.

Many thanks to Donald Friedman for base info on renovation and structures.

When Sony began to convert the ex-AT&T Building for its own use, it was apparent that the telecommunications facilities in the building were outdated -- despite that the building had been built only a decade earlier as a headquarters for a major telecom company!

The use of modern multimedia PCs and increased amount of data within in-building networks required new horizontal distribution for the telecom cabling. Also, according to old cabling standards each type of cabling had to use a separate routing, whereas the new cabling could be placed together in a common infrastructure. In addition to data communication, every office has also extensive facilities for plugging-in of audio-visual appliances.

As the AT&T Building was not built as an open office environment, unlike most modern office buildings, but rather as one consisting of office rooms with walls between, the distribution of the extensive cabling was possible to make as a fixed infrastructure within the cellular floors to the fixed walls -- there was no need to take into account possible changes in the furniture layout, unlike in the open offices. The telecom facilities were, all in all, expanded to fit the needs of the planned 1,600 Sony employees, as opposed to the 600 AT&T employees.

In addition to the telecom systems, also the HVAC (heating, ventilation, air-conditioning) systems had to be uprated. Sony wanted to increase the amount of rejected heat within the building by a quarter. The pediments on the roof of the building, where the cooling towers were situated, had the effect of circulating some of the emitted steam back to the towers, thus degrading their designed performance. By modifying the towers the cooling effect was increased by 17 per cent. Also the chillers in the building had been working under their rated capacity, but after a complete overhaul their capacity was increased by 25 per cent. By adjusting these installations, instead of a complete replacement, $1.5 million was saved.

Yet another area where the existing systems in the building were less than satisfactory was the air-conditioning system, more precisely the ductwork effectiveness. The needed air-conditioning volumes couldn't be reached without either modifying the existing ductwork or by uprating the fan systems. As there was concern about compromising the original Philip Johnson-designed ceilings, the fan system was uprated instead. The procedure brought additional costs of $3.5 million.

The lighting fittings were modified to suit the kind of work that the employees performed. The existing core fluorescent lighting used as ambient lightning around the building's circulation core and at the perimeter windows was retained, but the individual work lighting was made either as furniture-mounted lighting or as swing-arm lamps with their own switch, depending on the nature of the work and the office space. Additional lighting was also installed to specialty areas of the building.

The most visible change for the general public was the conversion of the existing open-space arcade at the back of the building into the enclosed Sony Plaza with its retail spaces and street-like plaza with cafés, trees and street lights. As a showcase for Sony's newest products,the plaza was designed with theatrical lighting, which in turn required an effective cooling system. As the cooling capacity of the whole building was already at its limits, a separate chiller unit was added for the plaza use. The snow-melting installation under the floor was retained, this time to warm the tile-covered floor of the plaza.

Info by Buildings.

After the recession of the building industry in the early 1990s, construction in New York City has revived, but renovation of old buildings has grown even faster. Although the amount of applications for new buildings is today only one third of the pre-recession level a decade ago, the employment has nevertheless revived to 80 per cent of the peak level. The reason is the increased work on building renovation, which has in the same time as much as doubled for the buildings with landmark status by the Landmarks Preservation Commission.

There are a number of reasons behind the growth in renovation. An office building of the 1930s and 1940s may have typically small floors, especially in the tower portion, and be unsuitable for installation of modern office building services, thus making residential conversion attractive. The office buildings from the 1950s and 1960s do generally have larger floors, but they also would need extensive refitting in order to house all the modern communication installations. Buildings of this era were also built with liberal amounts of asbestos inside, thus making a proper renovation and conversion feasible. Reductions in taxation for renovated premises also attract owners to "go the renovation way"; replacing an older building is no longer as economically viable a solution and less likely to return the investment, as opposed to renovating old premises. In fact, because of recent reductions in allowed building volume to a plot, the existing building can well have a larger internal volume than the new one would.

The increase in renovation can be traced back to the 1980 city law that required regular inspections and maintenance of buildings over six storeys. The utilization of tax incentives introduced in 1990 for the Wall Street area renovation and conversion, along with the financing difficulties of new projects during recession added to the popularity of renovation.

The diminished assignments on new projects forced also designers to specialize in renovation rather than merely concentrate on new construction. Luckily for them, the image of the older buildings also often attracts tenants, both firms and private persons, more than the interiors of the post-war International Style buildings. At the same time, also the Modernist office buildings are renovated and converted to other uses, like dwelling, which in some cases also requires strengthening of the frame as these high-rises are more prone to sway than the older ones with a more rigid internal frame.

Although parts of Downtown were rezoned by the city to allow conversion into residential areas, the expected pace of office building conversion, especially for the older buildings, was somewhat reduced due to the acute lack of office space in the late 1990s. The situation also led to increased rents throughout the city, and forced many companies to consider reducing their presence in the city or moving out altogether. As the vacancy rates started to increase again with the change of decade and the dot-com crash -- and finally with the attack on the neighbourhood in September 2001, which led to an exodus of commercial tenants and the spreading of companies' operations to multiple locations -- the change in demographics led to a renewed interest in apartment conversion, not least due to the introduction of state and federal financing programs.

Financial programs have been imperative in the current conversion boom: converting an office building into apartments is three to four times more expensive per sq.ft than renovating an office space. In September 2003, Cushman & Wakefield reported that there were 2,395 residential units underway, with 3,020 more in the planning stage. These were seen to be mainly rentals, due to the conditions of the federal financing.

Of the $8 billion in federal Liberty Bonds for 2002 onwards, $1.6 billion has been set aside for residential uses. In addition to the considerably lower interest rates for the loan, the bond program also allows certain NYC real estate taxes be delayed or avoided altogether. With the Liberty Bond program expiring at the end of 2004, there have been suggestions of redirecting some of the commercial portion to residential construction.

By September 2003, approx. $600 million in bonds had been approved by the city and the state; the bond program has, for example, provided $82 million for the conversion of a 27-storey building built for Bank of New York at 90 Washington Street into 398 apartment units (link).

Wall Street has increasingly become residential or been converted to hotel use and around City Hall and the WTC, the Woolworth Building is to have an all-residential top of 145 units, with a new rental tower nearby at 10 Barclay St..

In addition to a general shortage of apartments in Manhattan, an impetus for residential conversions has been the willingness of Wall Street professionals to pay well for a privilege of living near their workplaces. Approx. 35 percent of Lower Manhattan residents walk to work -- a more pleasing prospect than commuting every day in a crowded train or ferry.

Although the number of residential services like grocery shops and laundrettes is still modest in the previously all-office neighbourhood of Wall Street, the growing number of inhabitants is expected to lead to an increase in these too.

The rising prices of residences in 2005 have kept the conversions coming, with even such venerable NYC institutions as the St. Regis and Plaza hotels announcing plans of converting part of their guest rooms into apartments. After a change of hands, the ex-Metropolitan Life Insurance Co. Tower at 1 Madison Ave. will also face a residential makeover, albeit only on the inside, due to the national landmark status of the exterior. The relatively small floorplates of the tower are more suited for residential than office use, and the floors have, moreover, a higher than normal ceiling height, always a plus in high-price apartment marketing.

In March 2006, there are around 20 new conversions underway in the Financial District, totalling 560,000 m² and adding to the 650,000 m² already given the residential makeover (CB Richard Ellis). And with such re-born heavy-duty luxury addresses as the 23 Wall Street (renamed simply the "Downtown"), 20 Pine Street ("Collection by Armani/Casa" -- don't ask me) and the 55 Wall Street ("Cipriani Club Residences"), the Downtown conversions have turned the page on the first tentative and relatively bargain-level rental redevelopments of the 1990s.

Info by The New York Times, New York Post, Fortune and The City Review

The development of more and more advanced telecommunications systems has not only improved the corporations' ability to communicate with the outer world, but also the ability to disperse their own activities. In both counts New York City (together with its surrounding areas) is perhaps the leading example in the USA, with the telecom-extensive infrastructure and the amount of downtown headquarters with dispersed back office activities.

With the invention of the telephone, the ability to communicate within a high-rise office building's different floors improved notably, reducing the need for messengers. It also gave a means for communicating between different buildings in a downtown area -- and as time went on, also diversifying the locations of a single corporation.

Cost-effectiveness has usually dictated the moves of parts of a company's staff and operations to different parts of a city, country or even worldwide. With differing costs of land, labour or taxation (there are of course other variables, like the raw material costs and more lenient legislation, which will be omitted here as this text will concentrate on office locating -- the overseas-relocated facilities often also lead to less than favourable contracts for the local workers...), relocating operations becomes an attractive option.

Relocation of the so-called "back office" activities to a secondary location has been a rather standard procedure for many New York corporations, although the Manhattan locations have increasingly changed to ones across the rivers. Along with the economical factors favouring a relocation either to Long Island or New Jersey (the "Manhattan West", as it is being marketed), the ready availability of trained suburban workforce favours this trend. While a downtown location would require time-consuming workforce commuting to Manhattan and back, a suburban location gives them work nearer their homes. Although ecologically not perhaps the best example, this nevertheless allows the workers to also better utilize their cars as transportation (see Car Parking for some reasons for them to not drive it into Manhattan!) and reduces the need for the employer to provide alternate (=safe) means of transportation home for nightjobbers. In addition, the fear of the workers forming unions should not be overseen as an impetus behind decentralization into smaller units.

In the cases of dispersed operations, telecommunications systems allow the different locations and branches to keep contact with each other and allow efficient supervision from headquarters in a yet another location, usually a dowtown headquarters building.

Since the 1950s, when the main industries in New York City were still manufacturing, trading and transportation (with shipping still strongly in the picture), gradually the improvement in telecommunications led to dispersal of these firms' activities (with only the main office functions remaining in Manhattan downtown areas) or a total relocation, while banking, securities, advertising etc. took over as the primary type of business. New York City is now more or less the center for these activities in the USA. Functioning also as the nation's premier international messaging center, the NYC business hubs have extensive coaxial and fibre link installations for high-speed communications, as well as satellite connections. Together with the record number of telephones as well as expanding commercial computer network usage, the companies utilizing telecommunications as a tool fit very well into the mould of telecom-dependent businesses of NYC.

The latest addition to these telecom-intensive trades have been the information technology companies. Due to lack of suitably-equipped office space elsewhere, these companies often occupy older converted manufacturing, warehouse and office buildings in the Garment District, TriBeCa, Flatiron area etc. "retrofitted" with high-speed network connections, often provided by the landlord as an incentive for these high-rent businesses. With the "dot-coms" riding the wave of the turn-of-the-Millennium business trend, they will continue to flourish in New York City and at the same time further change the balance between telecom-reliant companies and the more traditional trades in New York City.

28 Oct 2001:
With the (after all) eventual fall of IT businesses worldwide, the massive investments into telecom and datacom installations have been in many cases lost and the retrofitted properties vacated. Had these firms still been around in Downtown and TriBeCa when the attack on the
World Trade Center occurred in September 2001, they would have suffered further due to the evacuation, physical damage and power shortages. Even well-prepared firms, like Lehman Brothers, had a hard time after the attacks despite their extensive redundancy (and in Lehman Brothers' case the long-term effect was cushioned by the ready availability of a whole, brand new Class A office building it managed to get hold of at the right time). Now, however, with the large corporations in the IT and finance sector seeking secure locations for datacom operations (and for a large part of the staff), some specialized "telco hotels" in Downtown or New Jersey (the latter also on a different powergrid than Manhattan) -- or even further afield, adding distance between locations as a protection -- have been able to replace part of the lost tenants with these activities. Although the main operations may still be retained in Manhattan locations, a backup operation center is an increasingly viable alternative for many datacom-dependent corporations. That allows them to remain online and operational even in the case of disasters like the September the 11th.

The most extensively-equipped of these backup locations have their own power generators for electricity and air-conditioning (as an important factor for rooms filled with heat-belching computer servers as with people) so that in case of power failures or supply shortages they can remain operational. Data from a company's main operation locations is sent regularly to the backup facility to be available for continuing of operations. The re-occupation of these specially outfitted buildings is essential for their developers -- it is five to seven times more expensive to outfit a floor for telecom tenant's needs than for ordinary office use. Despite the re-assessments of the corporations, the vacancy rate of telecom space in Manhattan is still a hefty 38%. Also Midtown Manhattan is emerging as a backup location, with the Durst Oranization's CyberCenter in West Side waterfront opening in fall 2003. (26 Dec. 2004: The location of the cancelled CyberCenter will house The Helena, the environmentally-conscious apartment building instead.)

29 October 2002:
The draft proposal for regulations concerning the backup locations by the Securities & Exchange Commission, the Federal Reserve and the New York State Banking Department has faced severe opposition. The draft requires nearly all financial services companies to provide a backup location that employs its own, complete, staff and has infrastructure, power, water and transportation services independent from the parent locations. The requirements are seen as a strain on the companies' finances, especially as the companies usually have already made arrangements to disperse operations.
12 February 2005: The guidelines, calling for a backup location in "a different region" -- nevertheless, a milder requirement than the original 300-mile minimum radius of 2001 -- require these locations to be in place by April 2006. Although 90 percent of the companies themselves claim to be able to meet the deadline, it is more likely that only approx. two-thirds of the companies affected will make it. The companies will have to be able to recover operationally in two to four hours' time, depending on the importance of their role. Some take the advantage of "forced" operations reassessment and build extensive remote facilities with fully upgraded computer clusters. In addition to financial firms, also companies from such diverse industries as entertainment or insurance have showed interest in remote facilities, in order to ensure continuity in case of any upheavals that could affect operations.

Expanded from info by Intermedia, The New York Times,
New York Post and Slatin Report.

As a sign on the times, even such entities as the bulky, light-stealing and energy-hogging skyscrapers are being turned into prime examples of the environmentally-conscious thinking.

Already the energy crisis of the 1970s saw a number of attempts at reducing the Con Edison bill total, but examples like the (uninstalled) solar panels and double-decker elevators at the Citicorp Center were only short-lived experiments that the lavish 1980s soon put to rest.

Solar panels have made their way back to the City with the new pioneering examples of "green" office and residential skyscraper design. The office tower of Condé Nast at Times Square and the planned "environmental" residential tower in Battery Park City are the first "serious" examples of their kind in New York City.

These buildings deploy solar panels on the facades to cover a portion of the electric needs -- in Condé Nast about 1.5 per cent of the total consumption. The building has also two fuel cells that will cover the electric needs of night hours.

Geothermal heating is still untried in high-rises, and even the almost-pioneering (low-rise) building in TriBeCa, with, for example, a cinema for gaining heat loads from the crowds, was not equipped thusly as the developers chose not to pursue the idea. But if it works in such a large scale, the idea of gaining heat during winter months from the "pool" of constant-warmth rockbed/soil and, on the other hand, dumping the cooling heat to warm the ground for future use instead of puffing it to the sky is a sound one.

The use of so-called green roofs is seen as a way of the future for environmental-conscious development. These are flat roofs that are covered in dirt and plants that together absorb both heat from the sun and rainwater, reducing the heat load on the building and the need for air-conditioning as well as the amount of rainwater to be plumbed away. The plants used range from moss to full-grown grasses and give the roof (partly) its name.

One example of such an undertaking is the all-around green building, The Solaire in Battery Park City. The Durst-developed 38-storey apartment building, The Helena (under construction in 2004) at 11th Avenue and 57th St. will have a 900 m&178; of green roof.

The costs of building a green roof are notably higher than those of a traditional one, even more when replacing an existing roof with a green one, and also the maintenance costs are higher, but a green roof has a longer operational lifespan. Partly due to the reduced temperatures on the roof itself -- covered with the layer of dirt -- a green roof is estimated to last twice the 20-year span of a typical traditional roof.

The main factor supporting the construction of green roofs is, however, their effect on the immediate environment in terms of air quality, heat and water absorption, as well as the more widespread reduction in citywide heat load caused by large dark surfaces such as bitumen felt roofs or asphalt surfaces that cause an increase in outdoor temperatures and the amount of ozone, a component of smog.

Chicago has, in fact, been preparing regulations that would award green-roofed buildings up to one-third of their rainwater drainage fees and give development bonuses for buildings with 60 percent or more of their roof area as green roofs.

Alternate methods of water replenishment can reduce the need for fresh water use in the building. The "gray" waters of household washing etc. waste-use can be cleaned and recycled for secondary usage within the building, like toilet flushing or outdoor plant-watering. This method suits a residential building better than an office one, apparently. Collected rainwater can be used for these purposes as well as to replace water in the interior air lost in evaporation or to replenish the building's sprinkler tank.

In addition to these equipment-intensive methods, also the older -- and constantly improving -- material-based solutions, like new thermal and sunshielding (yet at the same time requiring better light transmittance to decrease need for artificial lighting) glasses or double facades, reduce heat losses (and then again, need for cooling), and thus operating costs, considerably. The quality and greener methods of manufacture of materials, including recycling, as part of the sustainable development also add to the environmental equation. As is the minimal use of so-called volatile organic compounds (VOC), materials and chemicals that may carry health risks, a consideration for the occupants at least.

Other, indoor-environmental or, indeed, habitual methods add to the savings and environmental-friendliness: the circulation of indoor air, reduction in air temperature, the extent of the freezing air-conditioning or the use of non-ozone-destroying cooling chemicals in the chiller units as well as switching off the unnecessary lighting, automatically or manually, more savings would certainly be forthcoming. But apparently not so much in the advert-intensive Times Square area!

The Leadership in Energy and Environmental Design (LEED) award is annually granted by the non-profit US Green Buildings Council to a building that exemplifies good environmental design. Although no building in NYC has so far won the award, the new 7 World Trade Center and Hearst headquarters are both expected to be in contention for the award as they are completed in 2005 and 2006, respectively. The buildings will apply for the award under different criteria: the 7 WTC will meet the less extensive "core and shell" criteria for tenant buildings where the developer has less influence on the full environmental choices (or lack of) that tenants may make, whereas the owner-occupied Hearst tower seeks the award under the full LEED standards. Although not originally designed with city downtown buildings, not to mention high-rises, in mind, the award criteria are hoped to adjust to the needs of 21st Century urban development.

Given the amount of energy and water that a single skyscraper, office or residential, eats up in a day, the idea of reducing the costs and consumption is a laudable one. The abovementioned buildings are leading the way. Although the savings gained by their green installations are still only a drop in the sea, they'll still add to a nice yearly amount of savings and may even pay back the equipment investment before the buildings' lifespan is over...

See also: Office environmental control and air-conditioning, heating and lighting.


By shaping the city with his technical prowess, man has also changed the natural environment he lives in. The expanding city not only moved the original, forested areas farther away from the people living in the city (although, fortunately, man-made parks, like Central Park, were made as a compensation), but also the in-city environment was changed as new high-rise buildings rose to the skyline.

The building of large concentrations of skyscrapers to New York City was to a large degree made possible by the subsoil conditions on the island of Manhattan. The bedrock under the soil is not only very old and stable -- the Fordham gneiss, Manhattan's oldest subsoil rock type, is one billion years old -- but also lies relatively near to the surface in Midtown Manhattan (although in Downtown it may occasionally be too deep to reach), allowing the use of foundations extending to the bedrock without unpractically deep digging.

At first, the solitary new skyscrapers were warmly welcomed especially by the gladdened male voyeurs who gathered at the 23rd Street apex of the Flatiron Building to wait that the strong wind hitting the walls of the building would turn upward -- at the same time lifting women's skirts high...

As the number of skycrapers increased, the laughter was over. Wind passing through the street "canyons" between skyscrapers tends to bounce off the ground and the sides of the building, creating columns of rising air. This canyon effect lifts litter from the ground and makes the holding of an umbrella a test of strength. Moreover, the buildings form a "venturi" gap, increasing the speed of wind considerably, and during winters the fast-blowing cold wind further lowers the cold temperature.

The skyscrapers have, quite naturally, affected the way the lightnings hit the ground in New York City. As tall buildings they attract the lightning strikes in their neighbourhoods; located in an area with a moderate lightning occurrence pattern, NYC gets 3.8 strikes per sq. mile every year (California gets 2 and Florida 20 to 42) -- a building with the height of the late 1 World Trade Center with its TV mast is struck approx. 35 times a year -- the Empire State Building gets similar amounts of attention.
Although lightnings normally occur when the negative charge within the thundercloud hops to meet the positive charge it induces on the ground, tall skyscrapers can act literally as such, scraping the low-lying (relative term) clouds and thus acting as a conduit for the energy release, sparking the lightning (pun intended). In these cases the lightning actually starts on the ground (the building) and moves upwards. The tallest skyscrapers in the vicinity of storm clouds are the most likely to get struck by lightnings -- the WTC towers had a grid of copper wire that routed the energy of the lightning to the bedrock via the structural steel of the frame.
Although a skyscraper can touch off a lightning in a thunderstorm and, in principal, absorb the current in the cloud that would otherwise strike at some other point, the height may be of great importance. In August 2002, a man was killed as he was struck by a lightning on the rooftop of a six-storey Broome Street apartment building -- it has been speculated that had the WTC towers have been still around, the towers could have received the discharge instead. With no similarly notably taller buildings around in Downtown to attract the lightning strikes (the next-tallest, the 70 Pine Street is a whopping 230 meters lower than the 1 WTC with its TV mast), the strike patterns will become more unpredictable in Lower Manhattan.

As strange as it seems, the peregrine falcon has adapted to live in the large cities of the USA. New York City has in fact the world's largest concentration of these birds of prey in an urban environment. After being decimated from the city due to the use of DDT in the 1950s and 1960s, the population has been re-bred, and in 1998 there were 15 tracked pairs nesting in NYC. The birds nest on the piers of bridges and on skyscrapers, and they control the ample population of pigeons, sparrows and starlings in the city.

The December 2004 debacle over the removal of the nest of the red-tailed hawk Pale Male (link) and the supporting spikes at 927 Fifth Ave. brought very visibly forward the fact that such winged predators live and prey (and litter) in this urban habitat. After intensive protesting against the removal of the nest, in place since 1993 and birthplace of 23 surviving youngsters (3 have died), the co-op board relented and promised to reinstall the spikes and restore the nest.

The skyscrapers also have a more ominous effect on the bird populations of the city, or ones migrating through it. The interior lighting or facade illumination of nighttime and the reflective glass in daytime can both fool birds to fly into the windows, causing death or injury. The spring and fall migration seasons are especially dangerous as a large number of birds pass through the city, navigating by stars -- and often mistaking a lit skyscraper for more stellar lights, especially during overcast or low-ceiling nights. In NYC, nearly 3,000 birds get killed annually, the white-throated sparrow getting the most "hits" (600 dead and injured), but, surprisingly, no seabird strikes and only five pigeons. And in six years, only one predator. In the whole of US, an estimated 100 million birds get killed on man-made structures each year.

Single skyscrapers -- like the Empire State Building -- are more prone to cause deaths than tower clusters. Before 9/11, the nighttime illumination of the Empire was, in fact, switched off during the migration season, although that practice was discontinued as a morale-boosting gesture after the attacks. In Chicago, with prominent skyscrapers like the Sears Tower and John Hancock Center, the practice has been continued, saving yearly an estimated 10,000 birds in Downtown Chicago, a popular destination for birds crossing Lake Michigan, the location of several hundred thousand fatalities. (The severity of the problem can be gauged from the fact that whereas in 2000, the World Trade Center -- a pre-9/11 focal point of NYC preservation effort -- and World Financial Center had 1,000 recorded hits, the Hancock Center had recorded in 1969 a single-night massacre of 400.)

The use of patterned glass is seen as an alternative to dimming or switching off the interior lighting -- it will, moreover, be effective also during daytime, breaking the reflections of outside features or sky as well as the scenes of lobby greenery. A type of glass with UV properties is under study to make it visible to birds.

From 2005 on, with the program Lights Out NY, a number of NYC skyscrapers -- including the Empire State Building (which has had a dimming policy of its own for decades), Rockefeller Center, Chrysler Building and the World Financial Center -- will be radically dimmed during the migratory seasons in April-May and September-October. The policy is the result of a proposal from the city and the Audubon Society for citywide voluntary dimming, especially of buildings over 40 floors and all glass-walled ones along the East and Hudson Rivers. NYC Real estate groups are actively promoting the policy, not least as savings from decreased use of electricity in a 230,000 m² building, for example, can exceed $100,000 per each migrating season and $600,000 annually. Toronto has had a dimming program in place since 1993 and Chicago since 1999, including 100 buildings.

The History Channel: Nesting in the Clouds
The Peregrine Fund
The New York City Audubon Society
Lights Out NY

Although the popular conception of earthquakes in the USA places them firmly to the West Coast and the plate boundaries there, that's only one part of the story. Also areas deep within the plates themselves can, and will, have earthquakes.

Of the annual over 900,000 earthquakes worldwide, most are minor tremors well under magnitude of 2.5, with serious ones of 8.0 occurring only at 5 to 10 years' intervals. Although these generally occur in plate boundaries, the most severe earthquakes -- recorded ones, that is -- in the USA have actually occurred in intra-plate areas, areas within the plates themselves. The three record earthquakes in the USA all took place in New Madrid in Missouri between December 1811 and February 1812. They ranged in magnitude from 7.6 to 8.2. There were also no less than 203 damaging aftershocks.

Of these intra-plate earthquake areas, Charleston, South Carolina, eastern Massachusetts, the St. Lawrence River area and the central Mississippi River Valley are those mostly affected. Although southern California has 100-fold earthquake activity as compared to New York State, over 400 pinpointed earthquakes of over 2.0 magnitude have been nevertheless recorded in NY between 1730 and 1986. The state has been the third most seismically active of those east of Mississippi River.

Two notable earthquakes have occurred in New York City: the 5.0 magnitude tremors in 1737 and 1884, both originating from Rockaway in Queens. If the time between the earthquakes and the time since the last one are studied, the likelihood of the next occurrence is about 50 years away, although any specific possibilities are hard to come by due to the relative lack of earthquakes in the NY State. General estimates for a 5.0 M occurrence are about 200 years, 6.0, 600 years and 7.0, 2000 years. Of course any estimated likelihoods are just that, likelihoods, not necessarily having anything to do with the actual occurrences -- such earthquakes could occur also on following years, or months...

A "critical" earthquake in the New York City area has been estimated at the value of 5.8 M. But due to the circumstances in the city and the numerous shortcomings in its structures and preparations such an earthquake would have an effect closer to the 7.0 M that occurred in 1995 in Kobe, Japan. The estimated maximum for an intra-plate earthquake is about 8.0, the size of the New Madrid earthquakes. The situation and expectations are not helped by the fact that about 80 per cent of the nation's earthquake-hazard prevention budget is spent in California and Alaska, with preciously little reserved for other parts like New York City.

Although the reasons for intra-plate earthquakes are somewhat a mystery, one reason for the seismically relatively active conditions in parts of the East Coast can be traced to the time when the African continent was joined with North America. On the separation, approx. 200 million years ago, it left behind a formation, Cameron's Line, that runs through New York City roughly along the East River, to Staten Island and beyond. The corresponding parts in Africa and North America share not only similar geological formations like brownstone and red sandstone, but also the ability to produce earthquakes of up to 7.5 M. In addition, the relatively cooler underground temperatures in intra-plate areas, when compared to California, have an additional effect of increasing the area that an earthquake affects. Because earthquake tremors travel more effectively through cooler rock, a strong earthquake even quite some distance away from NYC could hurt the city -- an earthquake in Charleston in 1886 cracked walls in Harlem and was felt all the way in Omaha.
(See also: commentary)

As for the subsoil conditions in NYC itself, the well-known Manhattan bedrock rises to the surface in the northern part of the island, extending also to the north. The bedrock falls deeper as we go to the south and east, forming still a reachable foundation for buildings in Midtown, but generally not as far south as in Downtown. Because bedrock forms a solid base for a building, it, despite also transmitting seismic shockwaves effectively, will be a better choice than soft soil. The ample soft soil in New York would be the cause for the city's major harm in case of an earthquake. Not only does it amplify the seismic waves and direct them to the surface, but parts of the city land are also prone to so-called liquefaction, an abrupt loss of soil cohesion. The sand particles lose their friction resistance under the earthquake vibration and get mixed up with water beneath the ground surface, naturally losing any support it gives to a structure. A particularly clear example of its effect was the accident in Brooklyn, where building a sewer in reclaimed land with a vibratory pile driver collapsed four houses within two blocks with the loss of a life. The agitated soil had given way even from that distance and led to the collapse. Much of the waterfront is filled-in and reclaimed from the rivers with soil that is prone to liquefaction, especially below water level. The most notable of these landfills is the Battery Park City in Downtown Manhattan, which would face severe problems in a major earthquake -- as would do many other vital services, like several major hospitals or the Long Island airports on fills, with JFK also near Rockaway.

The structural frames of buildings differ also in their resistance to earthquake tremors -- a steel-framed high-rise building, maybe surprisingly, being the (relatively) safest. The ones to avoid in NYC would be its numerous brownstones and "walk-ups", masonry and brick-built, un-reinforced 19th Century houses -- in addition to a literal risk of total collapse (or partial, of floors, stairs or elevators), they and other apartment buildings could also shower(!) the streets with decor sculpturing and air conditioners. The old buildings housing the city's fire companies also could have problems like jammed doors due to collapses, making a dash out a bit problematic... Similarly, also collapses of schools and armouries, of masonry and concrete, could set recovery back because these are designated as victim housing centers.

The subway might be a better bet than streets or building interiors. As well as effective bomb-shelters, the deep-dug stations of the "tube-built" systems in many cities would also survive better in an earthquake. Although the MTA subway is a dug-in shallow system closer to the danger zone in the surface, the stations may perform well enough as shelters, even with some sinking that occurred in Kobe. The NJ-NYC PATH tunnels are no place to be during an earthquake, as the old cast-iron tunnels are likely to be destroyed.

As well as threatening the subway system, earthquakes will also almost certainly sever the services running between street-level and subway tunnels. Water, rain and rainwater sewers, electricity, gas, phone cables all are prone to get severed in tremors, causing truly a disaster in the city. As much of the pipeline network for these services is old, pipes of wood and cast-iron, it is going to suffer severely. Also the two fresh water tunnels from upstate supplying nearly all the water to NYC are old and vulnerable to an upstate earthquake (they actually cross a fault line), which could sever both and leave the city almost without pipe water supply.

In a situation of fires raging within the city as a result of an earthquake -- it has been estimated that one would cause over 130 separate fires -- the loss of water supply or water pressure is simply unbearable. Add to that split gas pipes, loss of electricity and lighting and streets filled with abandoned cars -- as well as destroyed airport runways, bridges and tunnels -- and crime-fighting, firefighting, rubble removal, rescue and medical operations will be facing a severe uphill battle. With the need to get key groups into the now-isolated Manhattan -- like the large amount of policemen in Manhattan precincts living outside the island or the nationwide rescue teams or the Guard -- and the fleeing people out, the task isn't made any easier. The rule of "golden 24 hours" (which gives a 93% survival rate for people rescued in that time) would require swift actions -- delay it to 72 hours and 95% of the victims are dead. Even in the best of transport successes, the amount of destruction may well overwhelm the resources of even a large number of -- professional or ad-hoc -- rescue teams.

You really don't need a flying saucer flattening The City in a Hollywood blockbuster, in worst case the nature could almost provide such.

The method of searching for hitherto concealed fault lines is one means of trying to locate potential new earthquakes. By searching for natural marks from aerial photos that would indicate water or natural gas seeping to the surface through the fault lines, these lines may be located. So, lines formed by simple streams, dead or dying plants or autumn brown-coloured trees on an aerial photo can be an evidence of such lines. So far, only a few earthquakes have been able to be connected to the found fault lines' location, largely due to the inaccurate determination of an earthquake's origin point and the great depth (up, or rather, down, to 20 kilometers) whence they occur.

The New York City Seismic Code, which came into effect in February 1996, determines the conditions, design parameters and requirements for earthquake-resistant design and construction of buildings and their affixed components as well as independently standing structures.

New York City is located in an area with a seismic zone factor of Z=0.15, making it a city with a moderate earthquake risk. The east coast earthquakes characteristically release high-frequency energy tremors that travel long distances in the relatively unbroken bedrock present in the eastern USA.

The ground underneath the foundations of a building is divided into five classes of rock and soil, from S0 (rock) to S4 (soft soil), with the type present being determined by testing. Similarly, the susceptibility for liquefaction will have to be determined for the softer soil types in the presence of water.

The site coefficients given for each of these rock/soil classes reflect their respective susceptibility for ground motion; there is a 3.5-fold difference between the S0 value of 0.67 and the S4 value of 2.5, effectively providing notably more lenient seismic requirements for buildings built on bedrock. The code does not even try to counter the effects of a maximum earthquake possible in the area with the frames' elasticity, the tradeoff in such an occurrence being acceptable damage through designed redundancy in the frame, as long as the building can be evacuated safely.

The additional costs of strengthening a structural frame against seismic forces range from a few percent to over 10 percent of the total structural costs, depending on the type of frame, type of lateral strengthening, number of floors, setbacks, rock/soil type etc. The strengthening against seismic forces can also prevent much of the damage done by possible terrorist bomb attacks (up to 80 percent of the structural failures in the support of the main facade and the slabs in the Oklahoma City Federal Bldg. could have been prevented with a modern earthquake-resistant frame design).

In addition to new construction, the code also regulates alterations and expansions to older structures. New expansions with foundations require these as earthquake-resistant and non-founded expansions valued at at least 60 percent of the existing building require strengthening of the whole structure. The older, masonry-framed buildings are particularly vulnerable to earthquakes, and are thus a special target for strengthening of the frame. As one way of countering the danger from adjacent buildings, the code requires a gap of 1 cm for every 6 meters of building height, meant to prevent the buildings from hitting each other during earthquakes (an example is the expansion of the Bush Tower). The distance as a function of height is for protecting the usually-sturdy high-rises against the pounding by probably less engineered low-rises, rather than the other way around.

Through extensive computer modelling, the approximate effect of an earthquake can be "predicted". In a lengthy study, nearly 37,000 buildings in Manhattan were modelled through their characteristics and the applicable soil types, and a 6.0 M earthquake, centered near Rockaway Beach, was then unleashed. Although over 1,000 buildings were destroyed or suffered major damage -- predominantly in the Lower Manhattan/Villages area with the masonry buildings -- over 2/3 of the studied buildings remained undamaged. (Of the destroyed buildings, 106 were masonry buildings (also 871 damaged) and one had a steel frame (494 damaged); buildings with concrete (182 damaged) and wood frames (10 damaged) suffered no collapses.) The studies showed also considerable damage to both technical and lifesaving services -- especially below 14th Street -- as well as up to 250 dead or badly wounded.

The NYC Seismic Code

Earthquakes In The Midwestern and Eastern United States??!! (with a Risk of Damage map of the USA)
What Are Earthquake Hazards?
What Should I Do Before, During, And After An Earthquake?

Info by Compuserve New York Magazine Online, Geo.mtu.edu, Explorezone.com, Mceer.buffalo.edu, The New York Times.

Thanks to Rowan Kanagarajah for pointing out this for me
hitherto unknown "feature" of the City.

Stop press: Paul R. Whitaker sent me this e-mail to comment on the text above:

How is New York prone to rare earthquakes. Getting the facts straight.

This is for you to enjoy. I have spent a lot of time on this. No, not to criticize, but to help you. Though not a Geologist or a Seismologist, I have read and researched these areas a lot.

I find your site interesting and well put together. Should you want to post this, feel free. But hey - give me a credit for writing this. Which I have.

In advance, sorry about it being rather long. I had no idea it would turn out this long.


Reply: No matter. Good to get some feedback on any inaccuracies -- just goes to show the old truth that even, in principle, reliable sources can/will have something wrong.

You may not know this, but Africa did NOT collide with North America. We use to be all one continent called Pangea.

Reply: True. Although I'm no geologist ;^), I can't fathom why the source mentioned a collision. And why I copied it...

Due to the "Blanket effect" (When too much heat gathers under very large land masses); the continent ripped apart at what is now the Mid-Atlantic Ridge. It is still doing so. The Atlantic is getting 2 inches wider a year. This is why Africa(Mali area) fits into the US east coast from Boston down to the Carolinas. Also why the soil is almost exactly the same. Surtsey, Iceland and other islands are on the top of this. Africa is still heading north though, pushing the Alps, the Caucusus and the mountains through Turkey and the middle east upwards. Hence the earthquakes that are so violent in Turkey and the ceaseless eruptions of Etna in Italy.

Don't believe me? Check any atlas that shows ocean depths and you will see that big crack running down the middle of the Atlantic. National Geographic's atlas is a great reference.

Reply: Hum, I've been awake on my geography lessons all those years ago...

Great. Does this mean I have pushed you back to square one? No. Here are the geological forces behind potential New York quakes:

400 million years ago, the Western Hemisphere snaps away from Europe and Africa (making a very loud noise) and forms a 10,000 mile swamp. This swamp becomes the Atlantic Ocean. The Americas begin to slide westward and the fishing dramatically improves in Spain.

Reply: I've got the figure of approx. 200 million years ago -- in the Mesozoic Era -- for that?

Geologically, you cannot push something the size of North America without "a little resistance." You have also got the Pacific Ocean on the other side and it doesn't want to give up any of its territory. The Pacific is huge now, it use to be twice that size.

North and South America begin getting mid-plate fractures which causes uplift. The two best example of this are: (a) The Appalachians that stretch from Georgia to the Gulf of St. Lawrence and (b) the uplifting in Brazil that stretches from Paraguay east to Belo Horizonte.

Pay attention for a second, this gets complicated:

The Canadian shield is the oldest rock on the planet. The oldest part of it is in the in the area of the Northwest Territories in Canada. Way up near where the Mackenzie delta empties into the Beaufort sea. On a map you can see a wierd "Bird Shaped" lake. That is called Great Slave Lake. This rock turns out to be over 1,000,000,000 years old. (For the Americans, that's a billion for the English - its a lot, but not a billion. I know I am Canadian, but we call it a billion too.) Because of the makeup of this rock, it is very solid, very heavy and very thick.

So, along comes this Mid-Atlantic ridge split. Like a teenage brat, it thinks it's going to move the Americas west without any problem. The Canadian Shield looks at it with a certain amount of distaste and probably thought "yeah sure." The Hemispheres start to move.

For Human beings, patience is a virtue. For geology, it's a must.

With the resistance from the Canadian Shield and the Pacific Ocean plate, North and South America have areas that are far more willing to slide along than other areas.

What happens? Faults begin to open. One of the best, and earliest, examples is the fault in eastern Ontario known as "Mazinaw Rock" or "Bon Echo Provincial Park." This geological formation is two miles in length of a "Vertical Thrust Fault." The east side went up 350 feet and the West side went down 350 feet. Solid Granite rock being pushed around like it was peanut butter. Even five advances of ice that were two miles thick have had little erosional effect on this structure. This is only a small part of a fault system that goes from James Bay (That wierd looking part of Hudson Bay at the top middle of Canada), down through eastern Ontario, into New York state (Creating the Adirondacks) then near Albany, NY; it abruptly bends east then south down through the Hudson Valley. Hey, now you know why the Hudson river is so darn straight, it's following an old fault line.

That fault line comes out at the west side of Manhattan. Why there? Because Manhattan is a SOLID chunk of Granite.

Reply: Or gneiss and schist.

That is why the subways are so shallow in New York City.

Reply: Not to mention the ease of construction (a relative term), also in the mostly deep-bedrock southern reaches of Manhattan. Although tunneling rock is, all in all, cheaper as a method (especially if the rock is solid enough to not require extensive supporting), the operating costs and vertical movement of passengers are more favourable in a shallow-dug system. But there are long stretches of tunnels dug into rock, for example encompassing almost 20 per cent of the old IRT line(s), (including the second longest double-track tunnel cut in rock in the US), also incorporating one of the widest concrete tunnel arches in the world.

The fault got shattered during the last couple of Ice ages. Ice is really heavy and it pushed the land on the north side way down, it is now pushing back up. Hence, the frequent small quakes in Quebec. It too created a fault system. Right on top of the Bon Echo fault. This fault (another straight line for quite some time) created the St. Lawrence river valley (another essentially straight river.) This fault continues right under the middle of Lake Ontario (Causing Toronto to have certain "Earthquake building codes" for buildings over 30 floors.(No, they are not made out of snow and ice.))The fault bends southwest near Hamilton, ON. From hear it heads under Lake Erie where it enters Ohio just west of Cleveland. Then down through Ohio to near Memphis, TN. Other small faults fracture out from this and these are the culprits that caused all those 19th century quakes near Memphis, that caused a lot of people to turn to religion suddenly.

This whole system is the one that "Can" cause earthquakes in New York, Boston, Memphis, Cleveland, Buffalo, Washington DC, Philadelphia, etc.. However, the thing moves "Very slowly" compared to the San Andreas in California. This means that its "frequency of events" (earthquakes) happen hundreds of years apart. But because they are "Vertical thrust faults" the quakes can have more of a "First shock" that can do some real damage. Bear in mind, most of New York is built on solid granite. Sure, it will move during the first shock of a quake. But it will move like a chunk of concrete: Back and forth a couple of times. What causes most of the problems during a quake is when you get crappy soils. The quake force rolls in and the area starts moving like a waterbed or a large thing of Jello. That is where you get real damage. The best examples of this are: The Marina district in San Francisco and the Mexico City quake. (Hey, let's build a city in an earthquake zone on an old lake bed. Let us also put it in a steep sided valley near the base of one of the nastiest volcanoes in the world. Then let us fill it with 19 million people. Geologically, Mexico City is one of the WORST places in the world for a city. A close second would be Tokyo.)

This could be a problem in areas of: Boston, Brooklyn, Washington DC, Newark. However, Manhattan would likely only feel a couple of vibrational shocks then settle down.

Reply: The question indeed is how strong the couple of vibra shocks are. Although the island is largely solid stone (and enables much of the buildings and structures to be founded on it) that still doesn't remove the risk of damaging buildings and services on top of that bedrock that transmits the waves. Not to mention places like Battery Park City... The bedrock in Manhattan reduces much of the effect of any earthquake, but the lack of respective building codes and the antiquity of the below-ground services causes trouble also in the northern parts of the island (not least with walls cracking up there due to a quake a thousand kilometers to the south...). After all, as evidenced by the numerous quakes in the east coast, it's not quite like here in Finland, where there is also solid bedrock but no fault lines or quakes. The bedrock helps a lot, but doesn't make a "once-in-a-thousand-year" quake an impossibility.

I hope you enjoyed this "Essay of mine".

Reply: Yes, we did. Thanks. :^)










lo-go © e t dankwa 27 June 2014