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This article by Tricia Fagan was published in U.S. 1 Newspaper on October 6, 1999. All rights reserved.
From the Rubble, the Commons Rises: Part I
Story by Tricia Fagan
Photos (not available in web version) by Brian McCarthy
<P10>In the first week of September, 1998, SJP Properties
broke ground for the Commons, one of the first speculative commercial
office developments in Princeton nearly a decade. The plan was to
raze the 40,000 square-foot, one-story structure then standing on
the 25-acre site (at the intersection of Alexander and Roszel roads)
and to construct in its place two multi-storied corporate buildings
housing a total of 300,000 square feet of class A office space.
SJP, a Parsippany-based commercial real estate firm with more than
10 million square feet of in its portfolio, invited the architects
(Hillier), the investors (including Prudential and Fleet Bank), commercial
real estate brokers, West Windsor Township officials, and the press
to join company owner Steven J. Pozycki at a groundbreaking ceremony.
With the attractive renderings of the new buildings mounted on easels
— and the existing structure looming as the first obstacle to
progress — the developers made a promise: The buildings would
be done in less than a year, and tenants would soon be found to pay
A year later, as promised, the buildings were delivered. Here’s how
the job went, as described by SJP officials, including Ted Rosner,
vice president of construction and site manager; Rick Johnston, project
manager for Bovis Construction; and John DeLuca, principal architect
on the job from the Hillier Group.
Plans for an office building on this site had actually
been approved by the West Windsor Township planning board sometime
in the late 1980s, but for a variety of reasons that project had never
gotten off the ground. Almost 10 years later, SJP Properties purchased
the project and once again set things in motion.
Since the board approval on the earlier project was in place, SJP
asked Hillier to develop a new plan for the buildings and site that
would fit in with SJP’s corporate esthetics, but stay within parameters
already set by the planning board. "Because of planning board
requirements," says DeLuca, the architect, "we had to maintain
parts of the project that had prior approval in terms of overall bulk
— how big it could be, how tall it could be, how many cars could
be parked on the property. SJP could have sought to modify the plan,
but they thought that from a pro forma standpoint it was fine the
way it was — although they did want to change the appearance from
the earlier design.
"Part of the issue for SJP was that they have a certain `brand
identity’ with the buildings they do. They wanted to bring some of
that to the project with the use of brick and limestone, to give the
building sort of a traditional feel with a contemporary line."
DeLuca noted that there were some interesting challenges in the design
process. "SJP wanted the buildings to be compatible with the Carnegie
Center, but they also wanted them to differentiate themselves. They
didn’t want somebody coming down the path to say, `Oh, that’s a part
of Carnegie,’ They wanted the buildings to be unique in some way.
We also needed to pay very strict attention to the budget because
it was a commercial building. Developers really adhere to a budget
as opposed to when you’re designing a civic building or a museum.
You have to be careful in the design process to meet the budget, but
to also create some decent architecture."
The project was fast track, so the final design and construction documents
were developed and approved within a matter of a few months. "With
all the building that was starting again along the Route 1 corridor,
clearly the first person to get in will get the tenants," says
DeLuca. "We were hired in March, design and documents were completed
— and approved by everyone, including the planning board —
and they were breaking ground by September."
It only takes the excavating subcontractor — American
Wrecking of Perth Amboy — a couple of weeks to demolish and cart
off the debris from the original one-story building that stood on
the site. "It was a clean, easy clear," Rosner and Johnston
agree. The licensed excavator carries the rubble to an approved location
where it is used as fill.
The day after the building debris is removed work begins on the extensive
retainage and detainment water system that undergirds the entire site.
West Windsor Township, like many others in the state, has rigorous
conservation requirements that developers are held to. This underground
system helps to control the substantial water run-off that large sites
of this type can create — channeling rain waters to natural channels
(like the creek running under Roszel Road) and to manmade sources
like the two new ponds created on the site.
To begin creation of the ponds, a CAT 350 excavator was brought in
— an impressive descendent of Mary Ann, Mike Mulligan’s legendary
steam shovel. Here work begins on the south pond, the larger of the
two. Eventually some 80,000 cubic yards will be removed from the site
to make room for the two ponds.
The pipeline for the sewage system to serve the site
is the other large underground component that needs to be completed
before actual construction begins on the buildings. Here the pipeline
has been set in place, and is being hooked up with the township’s
As soon as the underground systems are in place work begins on the
foundations of the buildings. DeLuca explains that the design of each
building’s foundation has a lot to do with the soil. Soil tests determine
how many pounds per square inch the soil can support without displacing,
deforming, or resettling. For the Commons, soil tests run at a laboratory
determined that the soil composition was good and that spread footings
could be used — which is similar to what’s used when building
an average house.
"They’re called ‘spread footings,’" DeLuca says, "because
they actually spread the load of the entire building over the size
of the bottom of the footing. Our structural engineer takes all the
design loads in the building and figures back to the column locations,
then down the columns to the footings, and then, ultimately, to the
soil to calculate how much of a building load each location can take
without becoming a settlement problem."
The thickness of the footing has to pick up all of the stresses coming
down the column so that the footing, itself, doesn’t crack. In this
case the footings are reinforced with a whole series of steel rebars
— and most of the footings used on this project measured 6 to
8-feet square, which bears a significant per square inch load.
When determining how deeply to set the footings, excavators need to
dig down until they’ve reached what they call virgin soil so that
they meet the compaction specifications represented in the site’s
core soil samples, and they also need to get below the freeze line
for that area. The rule of thumb is that the frost line is about 3
feet in this region.
Just a week after the foundation was completed, the
steel erection operation on the five-story building is well under
way. About 3,800 tons of steel will be used in the construction of
the two buildings.
The days of burning, red-glowing rivets are past. Many of today’s
new buildings, like the two here, are held together — in part,
at least — by TC (or "torque control") bolts. They have
been in use for the past 6 or 7 years, and are installed using a special
impact wrench that is set for the exact torque you want to achieve.
When the bolt is tightened to the required torque (e.g.., 300 pounds,)
the end breaks off.
To raise the steel, the steel erectors brought in a 65-ton crawler
crane with a 260-foot boom. "They could have done it with a smaller
crane, but these guys are professionals. It made the whole job go
easier," says Johnston. Both Rosner and Johnston were impressed
with the skill of the steelworking crew, from Interstate Ironworks
of Whitehouse Station. The frame went up quickly — with the steel
workers averaging 85 to 90 pieces of steel a day. "You don’t get
that many pieces a day unless these guys really know what they’re
doing. These guys were cooking," says Johnston.
Exact measurements for each aspect of the job need to be determined
in advance of starting a project like this. Many subcontractors do
advance work off site (using predetermined specifications) and then
bring their prepped materials — hopefully ready to plug in to
the construction on site.
"Steel’s a good example of this," DeLuca says. "There
are all different types of beams in terms of how deep or how wide
they are or the type of steel that they’re made from. Initially, a
steel mill somewhere extrudes the steel links out — kind of like
spaghetti — in some stock length (probably about 40 or 50 feet
long). Then they cut them — off-site — to the proper length
to fit into our building, and also modify the end of each beam to
accept all the proper bolts and rivets and to interface with the columns."
At this point one of the most important design considerations comes
into play. The building calls for vertical support columns spaced
at 30 feet. That’s important, says Michael Kaplan, executive vice
president for SJP, because "we like to do a structure in some
dimension of five-foot modules to accommodate office furniture systems.
If you use shorter spans it makes too many columns and not as much
open space. Longer than that and the girders that the columns support
become too deep and you have to reduce head room. The longer the span
between the columns the deeper the beam has to be. The beam is 24
inches for a 30 foot span. For a longer span it might have to be 3
to 6 inches deeper.
"We build it that way, not because it’s prettier, but because
it fits the tenant needs better," says Kaplan.
All the dimensions for the set-out of the building are included in
the original architectural drawings, and the structural engineer sizes
all the structural components in the construction documents to determine
how big each piece of each material needs to be. The steel subcontractor,
for example, studies both of these sources, hires a fabricator to
develop drawings of each one of the steel pieces required for the
project and develops a schedule for their portion of the project.
This is to be reviewed by both the design team and the contractor
to make sure that it’s correct before they go ahead and fabricate
the steel pieces. That whole process — working with each subcontractor
— takes about two or three months. "For everything you see
in the building," DeLuca says, "there is a process of suppliers
(or subcontractors) who have to provide information on what it is
that they’re going to bring out to the property for assembly —
and everybody has to go through that. That’s what we call shop drawings
Stoning to lie under the flooring on the ground floor
is delivered and in place, ready to spread, before the steel work
begins. Rosner explains that logistically it’s much easier to get
this step of the flooring process underway early on so that spreading
and grading can start as the steel construction continues on upper
floors — without the stone trucks interfering with the steel process.
Work continues on the giant runoff water system. These
massive storm lines run under the site’s access road. "Generally,
these are the biggest lines to go in," says Rosner, "so usually
they’re the first part of the underground site development to get
Johnston explains that these large pipes are just a part of the comprehensive
rainwater management system in place at the Commons. The buildings,
themselves, are designed to channel rainwater down from slightly sloped
flat roofs. Eighteen roof drains are situated around the center of
each of the buildings, in the area of the buildings core. The water
collects and runs down internal roof leaders buried inside the walls
and runs off in the drainage system below the building.
"The reason we took it to the middle and down the core," says
DeLuca, "is so we don’t have these leaders either encumbering
the exterior wall and affecting the windows — which would make
for bad offices — or have them out in the interior office tenant
space, which would start to take up a lot of rentable square footage.
We’re very careful when we’re designing speculative development buildings
that we make them as efficient as possible."
The retainment pond is still being dug. At one point the excavator
hit ground water in the deepest, most southern point of the south
pond and they had to bring in several sump pumps to get it dry (before
they laid the pond liner). Despite the drought that was on-going at
the time, it took more than five pumps working round the clock to
dry the spot enough so that digging for the pond could be completed.
Less than two months after the ground breaking and work
on the site is in full swing. The steel column and beam construction
on the five-story building is complete, and work on the foundation
and footings for the three-story building is already well underway.
Work has also begun on other aspects of site development, including
some of the sidewalks on the outer perimeters of the site. The low,
black fencing is a material called "silk fencing," yet another
conservation feature on a modern development site — this time
to prevent soil erosion. Each time work on a new site is started,
a civil engineer will study soil grade and wind patterns, and determine
where the fencing will go up. The fencing stays in place until the
plantings take and the soil on site stabilizes.
Work also continues on the storm drainage system. Since the road access
on Alexander Road was moved about 50 feet west, closer to the branch
bank there to improve visibility and traffic flow, the existing storm
system had to be extended out, and this new head wall for the drainage
system was put in place.
Steel work on the three-story building is moving along
rapidly. Three foot wide sheets of galvanized steel — which are
used as the base of the floorings/ceilings of the buildings —
have already been fitted in place on the bottom floors. These spans,
which are constructed so that they snugly overlap themselves, are
custom cut for each location.
Each sheet is secured in place, overlapping the adjacent piece, and
then welded to the steel beams below. Typically the beams are located
10 feet from center. Eighteen gauge sheets are used between each floor,
and 16 gauge steel on the roof.
Each step involved in the erecting of a building of this size must
be done meticulously since it lays the groundwork for all work to
come. Although unnoticeable to the lay eye, the slight groove created
on the outer edges of the steel framework by the steelworkers is an
essential element for the bricklayers soon to come. The precision
of this metal rim will determine how easily bricks can be set and
adjusted to the receiving angle.
All the players emphasize how much each subcontractor depends on the
work of the other subcontractors in making a project like this go
up smoothly and efficiently. DeLuca explains, "Typically, when
a lot of things happen sequentially in a job, we require the subcontractors
to confirm — when they can — things that have already been
constructed by taking measurements in the field.
With a project like this one, in particular — where the schedule
doesn’t allow for that — it takes coordination on the part of
the contractor, who brings all subcontractors together to agree on
final dimensions. Then, if a subcontractor comes back with a bathroom
vanity built to the proper specs and the opening in the wall is too
small, the guy who built the wall will have to come back and fix the
The wall panels begin to go up. Each section is made up of three layers:
structural studs, Dens glass (a rigid, non-load-bearing exterior sheeting),
and Tyvek building wrap.
So perfectly laid out they look like a solid grid, the
concrete precast grass pavers provide the erosion barrier for the
perimeters of the new ponds. By the time the top soil is spread and
grass has taken root these pavers will be virtually invisible. There
are a variety of other materials that builders use for this type of
job, but Johnston reports that they’ve found these grass pavers to
be the most all-around effective method to reinforce the sloping banks
such as these.
The underground conduit for the site lighting is laid.
The steel framing and interior flooring of the five-story building
has been completed, and the exterior panels have been attached on
most outer walls of the building. Pump jack scaffolding has been set
up around one half of the perimeter of the building so the bricklayers
can begin their work. Each section of this scaffolding operates independently
of the other sections. With the platform on the ground level, the
bricklayers load up with tools, bricks, and mortar — then operate
a hand crank to lift the entire load up to the level they’re working
on. "These are some incredibly strong guys," says Johnston.
Under ideal circumstances, the developer and builder would have preferred
to have all the building’s brick work done simultaneously. But "there
was so much building going on in the area this past winter," says
Rosner, "that we could only get the scaffolding and men to work
on half of each building at a time."
Landscapers have taken advantage of the unseasonable warmth of this
late fall and early winter to plant many new trees on the site in
time for their roots to set.
At this point you can see the soft curves which have become a signature
architectural detail of these buildings. "The buildings were designed
with this unique feature, which is formed by pulling a 178 radius
arc," Johnston says. "It all had to be calculated precisely
every step of the way. Any time you put circles on a building, it’s
hard to do. It takes a lot of extra work to make them happen."
"We felt the radius — that soft curve on the side of the building
— was really important to help give the buildings a real feature
from the Route 1 view," says DeLuca. "When we were developing
the design, we explored a number of ideas, but finally decided to
go with the curve — and it’s been really successful. I think it
really catches your eye."
He explains that the arc of the radius is not the same as the arc
of the circumference. "The radius of a circle is the distance
from the center point to the circumference," he says, "or
half of the diameter which is the distance all the way across. Imagine
taking a string that’s 178 feet long that you nail at a given point
and you walk it all the way around. That’s going to create an arc
at that radius."
"The important thing about the curve is esthetic," says DeLuca.
"It signifies the entrance to the building, and creates a design
element on the facade of the building that’s recognizable." Inside
the building, the arc creates a large, soft bay — 80 feet from
one end to another — on each floor. "From an interior standpoint,
it makes a great location for conference rooms and office spaces,"
DeLuca points out that, like many of the design elements incorporated
in the building, the curve serves multiple purposes. Along with the
esthetic and space enhancements, it also provides an eight-foot deep
protective overhang for the entryway to each building.
Just before Christmas and they are still hard at work.
Much of the bricking has been completed on the five-story building.
Pallets containing pre-measured pouches of grout are stacked out in
the staging area, waiting to be mixed by the bricklayers with sand
and water before being used to lay the bricks.
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