Industrial Rising

Industrial Rising by Edmund Klimek

High-rise warehouses? Trucks on the roof? Spiral ramps? Doesn’t sound like the typical industrial development does it? Multistory warehouse facilities are working overseas, creating new models of distribution efficiency. Are we at a point where multistory makes sense in the U.S., and if so what models will work for the Northeast? Here we examine the state of our urban industrial centers and what it might take for multistory to become reality.

Industrial Heritage

In the late 1800s and early 20th century, multistory loft factories were built in tightly knit urban manufacturing corridors along riverfronts and interior rail lines across northern New Jersey, New York and Philadelphia. The factories sparked the development of dense residential neighborhoods, which supplied workers by foot or streetcar. These multistory buildings typically employed “gravity flow” production the manufacturing of an item from the top floor down, with product transported off site via rail alongside the building.

The one-story industrial building was popularized by the introduction of the assembly line with Henry Ford in 1913 and, in the decades to come, the emergence of truck transportation as the primary means to move raw materials and finished goods. Industrial businesses increasingly found value in relocating to one-story facilities built on inexpensive land with convenient road access, off-street truck staging and employee parking naturally favoring suburban areas over older urban districts.

However, as industrial activity has evolved (from manufacturing to as much storage and product distribution), the pendulum is once again swinging back to urban centers for many of the same strategic reasons: they’re near rivers, railways, or residential neighborhoods that once supplied a strong workforce and can do so again. 

Add in rising fuel costs, the anticipated East Coast port-activity boon expected to accompany the 2014 Panama Canal expansion, and the availability and prevalence of urban industrial sites, and urban locales are looking ever more attractive. 

As city leadership looks to find solutions that improve vacant property and create jobs, industrial land more likely to remain open to industrial uses. As noted in a recent report by The Atlantic Cities, “there’s more potential in an abandoned warehouse than another set of high-rent lofts.” 

Places like Philadelphia are pursuing zoning strategies that favor a modern range of low-impact, high-performance or mixed-use industrial development. According to research by the Philadelphia Industrial Development Corporation, industrial jobs account for approximately 20 percent of the city’s total employment and contribute more than $322 million to the city’s coffers in direct taxes each year. In addition, these jobs have a low barrier to entry and offer a family-supporting living wage that typically includes a benefits package.

The story is similar in New York City, were the industrial sector is critical to the city’s economic vitality. Sunset Park, an industrial hub started more than 100 years ago, employs nearly 500,000 people (15 percent of the city’s workforce, and almost 20 percent of the workforce of Brooklyn, the Bronx and Queens) and generates $1.7 billion in annual direct tax revenue. Faced with the challenge of repositioning its older industrial building stock, Sunset Park recently completed a Sunset Park Waterfront Vision Plan, which explores how best to reposition the complex’s antiquated industrial infrastructure. 

Could multistory warehousing be a solution for urban industrial sites looking to repackage older industrial spaces constrained by tight lots and higher land costs? 

Multistory in Action

To date, modern multistory distribution centers have primarily taken off overseas. In Japan, Prologis has developed more than 20 multistory distribution facilities, varying in size from a two-story steel structure of 139,000 square feet, to an eight-story concrete tower of 1.4 million square feet. Using systems of full building ramps or separate spiral ramps for vehicle entry and exit, Prologis’ multi-tenant facilities eliminate the time and effort of moving goods by elevator. 

What makes multistory work in Japan? Land prices, parcel size and construction costs. 

In Japan, land prices per square foot of rentable space are considerably lower than the prices per square foot of the land parcel. The permissible floor area ratios in Japan’s industrial zones are as high as 400 percent. In contrast, the prices per square foot of rental space are higher than the prices of the land parcel in the U.S. when considering a typical single-story facility. Land parcel size is usually smaller in Japan as well - typically just 5 to 10 acres in Japan, compared to 40 to 50 acres in the U.S. Like land costs, construction costs are also higher in Japan. On average, the all-in construction costs in Japan tend to be roughly three- to four-times higher than those in the U.S. (depending on location and specific building features). 

Models for the U.S.

Similar to Japan, economic drivers are pushing industrial development back to urban centers, and space drivers coupled with the value of land will lead to pushing buildings up. The incentives toward urban industrial development include proximity to consumers, proximity to ports, the cost of fuel, availability of workforce and incentives to redevelop industrial brownfields. The reality is that America’s cities, especially older eastern seaboard cities, were industrially based and have inherent to them the natural infrastructure to support industrial development. Cities are returning to the notion that well planned industrial development can support their larger goals and quality of life, and are beginning to incentivize that development. Yet, even with re-zoning and lot consolidation, urban centers are constrained by the availability of space and the value of land. Responding to this conundrum of development leads to one answer: Up! 

Two immediate models present themselves for vertical development: 

Terminal Buildings

Terminal buildings provide for the fast turn around and transfer of product. They typically contain palletized material that is stored for short durations. They are often shallow, sometimes as narrow as 90 feet, and are organized around the need for the most dock locations possible. These can be intermodal facilities. 

What makes these buildings prime candidates for multistory development is that palletized storage can tolerate a higher degree of floor deflection, require substantially less clear height, as low as 18 to 25 feet, and can tolerate tighter column spacing. Further, these buildings are often built near port areas where soil conditions require the use of piles that typically have substantial spare capacity adding to their ability to support multiple floors. Further, these facilities are often arranged as multi-building clusters that allow ramp infrastructure to be amortized over multiple buildings.

The following are issues to consider: 

• Limit clear height: Typically these facilities only require between 18-24’ clear.
• Organize site development to amortize ramp infrastructure over more than one building.
• Organize ramps to in relationship to ground traffic circulation, minimizing turns.
• Take advantage of excess pile capacity by considering pile types.
• Limit structural loading: A typical terminal facility only requires a floor loading of 250 pounds per square foot for palletized storage as opposed to racked buildings that may require 500 to 750 pounds per square foot floor loading.
• Understand deflection: A floor can be designed as a good, hard, and even surface for fork lift traffic while still allowing for deflection. Deflections in a terminal building can be up to L/360 as opposed to racked buildings that would be limited to L/600 or even less.
• Keep the column bays reasonably tight: This is also a marketing factor that must be carefully considered. Spans that are closer to 40 to 50 feet are more economically delivered.
• Use readily available steel sizes: At smaller bay sizes with the greater allowable deflection, multistory terminal buildings can even utilize joists and joist-girders. Where this is not possible, however, special steel shapes should be avoided due to limited steel runs.
• Keep the building light! A greater factor in multistory buildings is the impact of building mass on seismic design. Also needing to be accounted for is the weight of product in the building. While utilizing pre-cast, tilt-up, or masonry construction can be considered for lower floors, consider the use of lighter materials such as metal panels for upper stories. 

Traditional Distribution with Rooftop Trailer Storage and Specialized High Storage Systems

Once away from the port or significant road infrastructure, the terminal building makes less sense, even in an urban setting. More traditional industrial buildings need to be considered in the constrained urban environments. Accomplishing this requires thinking about elements with similar criteria to terminal buildings and elements that would otherwise limit the development of building footprint. Also to be considered are creating provisions for newer and more mechanized systems of product storage.

Typical modern industrial buildings are 30- to 40-foot clear. They contain multiple modes of product storage and handling including palletized storage, rack storage, mezzanine access/ storage, and multi-tiered operations. Each user has a unique arrangement of these elements and these can change over time, requiring flexibility. Although less then terminal buildings, there is a demand for dock doors with associated lay-down space, optimally 60-foot deep. Also in demand, is trailer parking. Many industrial developments, even in a sub-urban setting, have failed to attract users because of the lack of adequate trailer storage. 

While seemingly incompatible with multistory development, there are elements and opportunities within this more typical industrial project type that can take advantage of going up. What matters most is to maximize building footprint, especially of those elements where loading is high and deflection is limited. This presents trailer storage as the best candidate of the program elements to be raised above the ground plane. And, in this scenario, the best location is likely the roof. 

The developer of an urban industrial project should consider other unique opportunities. A more urban location naturally lends itself to more sophisticated users and increased work force requirements. With respect to work force requirements, consideration should be given to providing infrastructure to stack support spaces above lay down areas that require less clear space. Also, consideration should be given to the potential user inclusion of more sophisticated, automated storage and retrieval systems. These systems can allow storage to occur at 85-foot clear or even more and provide for maximizing the storage potential for a limited site, even within a very small footprint. Typically rack supported, these systems require reinforced slabs. Ironically, however, they are not required to be flat with picking systems supported by their own rail. While specific layouts may be unique to user requirements, providing the general infrastructure or space to allow the user to develop such structures may be a positive in this development context.

The following are issues to consider:

• Move trailer parking to the roof: Building depths for traditional industrial projects will typically provide for two and often three rows of trailer parking.
• Consider site geometry for ramp development: It is best to design a straight ramp with limited turns. However, urban sites often contain remnant geometries that may be better taken advantage of with circular ramp structures.
• Design a durable roof surface: Roofs can be sloped with drains. However, the roof should be designed to have a membrane layer, an insulation layer, and a wearing surface or topping slab. Keep in mind trailer stands.
• Structural loading: By keeping racked areas on the ground plane, trailer storage or even palletized storage can be designed to 250 pounds per square foot.
• Understand deflection: A floor can be designed as a good and durable surface for trucks while still allowing for deflection. Deflections for truck parking can be up to L/360.
• Keep the column bays reasonably tight: This is also a marketing factor that must be carefully considered. Spans that are closer to 40 to 50 feet are more economically delivered.
• Use readily available steel sizes: At smaller bay sizes with the greater allowable deflection, multistory terminal buildings can even utilize joists and joist-girders. Where this is not possible, however, special steel shapes should be avoided due to limited steel runs.
• Keep the building light! A greater factor in multistory buildings is the impact of building mass on seismic design. Also needing to be accounted for is the weight of product in the building. While utilizing pre-cast, tilt-up, or masonry construction can be considered for lower floors, consider the use of lighter materials such as metal panels for upper stories.
• Consider areas for special industrial features: Reinforced slabs, sufficient power availability to introduce cooling and the ability to accommodate a workforce are all unique features of a potential urban industrial user.

Conclusion

With precedent set in places like Japan, many believing that industrialization may be returning to the America’s, and with the economic drivers of fuel, customer base and workforce requirements, industrial development will occur in constrained urban areas that present a real advantage to going up. Multistory development is possible and can be an economically viable solution to industrial models that respond to today’s user. Achieving that requires careful consideration of specific industrial functions and the unique opportunities that urban industrial development brings. 

John Harrison, of Harrison-Hamnett, P.C., and Tom Johnson, of KSS Architects, contributed to this article.