News & Insights

Strong Foundations for Urban Growth

Header_Foundations

BOSTON, MA Lovejoy Wharf. Chinatown. The South End. Longwood/Mission Hill. Waterfront wharves, where the ocean is just a few feet beneath; dense urban neighborhoods built on tidal marshes; urban districts packed with mixed uses and mixed needs—building on and in these distinctive Boston environments, takes some doing.

This summer and fall, Consigli teams will top-off the structural systems for three Boston residential high-rise projects, with a fourth close behind. From building ocean floor foundations to the use of innovative pre-fabricated structural systems, the construction solutions for these projects are as diverse as the neighborhoods in which they are being built. Together these projects are an intriguing snapshot of booming residential construction, and of the many ways Consigli builds.

Lovejoy Wharf’s Sea Change: Ocean Floor Becomes Strong Foundation

LoveJoyHeader

While snow was flying this past January, construction was underway at Lovejoy Wharf, underwater.

Installing a caisson foundation system beneath this North End wharf—one able to support the 17-story, 250,000-square-foot residential building rising above it—was the first step in Consigli’s construction of Related Beal’s Lovejoy Wharf waterfront condominiums. With views of the Zakim Bridge and a stone’s throw from TD Garden, the new 131 Beverly Street 185-foot high-rise, was designed by Robert A. M. Stern Architects, with local architect of record, ADD Inc. Abutting the already-transformed 160 Washington Street—now the new headquarters for sneaker giant Converse—this 162-unit tower is the final piece of the wharf’s redevelopment.

Working with sub-contractor Hub Foundation the Consigli team kept up a strong pace from late January to early May to complete this deep foundation so the next step, work on the building’s concrete super structure, could begin promptly this summer. This underwater support system replaces the wharf’s original wooden pile foundation, now much decayed. Now, beneath the new building’s 37,500 sq. ft. site, there is a system of 61 caissons, four-foot diameter underwater shafts filled with concrete. Building this support required drilling to depths of 80 to 120 feet—the equivalent of eight-to-twelve stories underground—beneath the wharf and eight feet down into Boston Harbor’s bedrock.

Once each shaft was drilled, it was pumped full of slurry—a mixture of water and clay—to keep each cylindrical hole intact before it was filled with concrete. Next, each shaft was filled with six truckloads—about 60 cubic yards—of concrete. Working at the steady clip of a caisson a day, this new foundation was completed in May, and the team is now readying the site for the arrival of its 220-foot tower crane, to begin the building’s cast-in-place concrete structure in July.

Over the next 21-months, Lovejoy’s final transformation will unfold with this high-end condominium’s 12- and 17-story structures going up, with its utilities’ infrastructure integrated, curtain wall set in place and elegant interior finishes installed.

One thing these new condos won’t have: parking. This is a first for a residential project of this scale in Boston—and it seems a fitting detail of this redevelopment that has already created three-quarters of an acre of new public waterfront at the wharf’s edges. Open to pedestrians this spring, this new water’s edge open space facilitated the reopening of the North End’s Harborwalk, bringing even more urban vitality to this reinvigorated corner of Boston.

Strategies for a Postage Stamp Site, Building Chinatown’s Oxford Ping On Housing

PingOnHeader

Remember the classic board game, “Operation”? Where players pick up awkwardly shaped objects with tweezers and move them oh-so-carefully out of small, cramped spaces? It turns out Consigli’s construction of the Chinese Economic Development Council’s new affordable high-rise housing in Chinatown’s tight quarters, requires similar skills—on only a slightly larger scale.

At the best of times, building in Boston’s Chinatown is a construction challenge: for Consigli’s Oxford Ping On team, whose postage stamp-sized site sits between two alley-like streets, it calls for innovative scheduling and site management. The 11-story, 60,000 sq. ft. high-rise sits on a 6,500 sq. ft. site, and it will fit with just a foot to spare between adjacent buildings. With 16 months scheduled for construction and little room on-site for material storage, the precise management of material deliveries and crew scheduling is crucial.

The Oxford Ping On project shot out of the gates in mid-November 2014. From installation of a steel-pile and lagging retaining wall, and digging deep to solid soil, to preparing this former urban fill site for its cast-in-place concrete foundation, to figuring out the geometry needed for the site’s 270-foot crane for maneuvering steel beams in place directly from truck beds, to this July’s placement of the final beam, the team is speeding toward the March 2016 finish line.

What’s minimizing the impact of construction and keeping the project going at a fast clip? A variety of Lean project delivery techniques—from tried-and-true techniques including just-in-time material deliveries and use of the Last Planner System® for managing on-site work, to the use of Line of Balance (LoB) scheduling to graphically illustrate the connection between production lines on a project and vPlanner—one of the industry’s most progressive software offerings for managing projects as production systems.

Consigli’s Project Manager Matt Lagowski explains that the Oxford Ping On project is perfect for the benefits of Lean project delivery techniques. “Scheduling needs to be absolutely reliable for this project’s sequencing of materials and crews, and this is where the use of the Last Planner System makes the difference. The Last Planner System provides a framework for Consigli to work with our trade partners to create more precise look-ahead schedules—and are especially useful for projects with repeated blocks of construction activity such as high-rise construction. Adding LoB to our lean toolbox allows us to see the gaps on the schedule that symbolize inefficient labor projection. This forewarning guides the collaborative scheduling efforts with our trade partners. Then, LoB also helps us coordinate material deliveries so they arrive just-in-time for installation and don’t take up precious space on site for long periods of time.”

Other strategies speeding the construction of these 67 much-needed apartments include a creative pre-fabricated steel package and an innovative approach to getting the building weather-tight three months early—creating a host of other benefits.

First, the Consigli team’s customized pre-fabrication approach for the building’s 11-stories of stairs streamlined the installation process and created an even safer work site. By combining the pre-fabrication of the building’s stairs with the structural steel package, the stairs were installed with the structure, instead of later as part of the project’s miscellaneous metal work, which is a more standard construction approach. And, with the stairs in place, ladders are not needed to access upper levels, another safety plus.

Second, the team recognized that the addition of a second vapor barrier to the roofing system—one that would function as a temporary roof membrane—would allow them to enclose the building sooner. With the building weather-tight, a neat sequence of expedited work falls into place, like dominoes: the installation of electrical systems and interior finishes could begin sooner and then the installation of the interior freight elevator moved ahead a month, allowing the team to free the site of the project’s monster hoist sooner—whose 200 sq. ft. base also takes up valuable site real estate.

One more project efficiency: the team’s use of swing-staging suspended from the roof to provide access to the exterior of the building, allowed the project to avoid the need for scaffolding on site. Together, all of these strategies are making 67 new homes for Chinatown’s community possible and sooner than originally planned.

600 Harrison Avenue: Hip New Housing’s Firm Foundation; Hybrid Structural System

600HRRSNHeader

The really big hole in the ground—420 feet long by 60 feet wide, to be exact—at 600 Harrison Avenue will soon be the South End’s SoWa district’s newest hip housing in this former industrial neighborhood, now in transition. Being built for New Atlantic Development and designed by architects from Boston’s Utile, Inc., Consigli’s team is using innovative construction techniques to turn this 35,000 sq. ft. brownfield site, formerly a parking lot for the Cathedral of the Holy Cross, into seven-stories of urban living.

Essentially a new city block, Consigli’s Project Manager Jeff Cammuso, talks about the work underway with a lot of energy and enthusiasm, comparing the seven-story by 420-foot-long residential development to building a “40-story high-rise—on its side!”

“Another ‘Green Monster’—that’s what it looked like we were building at first, before we had the block-long wall of 45-foot-tall sheet piles driven into the ground for the foundation’s outer edge.”

Building this multi-family housing’s foundation and its two-level, 162-space underground parking, is taking a level of care and attention that will be invisible to passersby when the project is complete, yet vital to turn this former tidal marshland into a watertight foundation.

“Because this edge of the South End was built on marshland, our site’s water table is at just beyond four feet. To make sure the below-grade parking is watertight, we used the ‘Ultra Seal’ process, installing a waterproof mat below the foundation slab and along the sheeting. After each step, we implemented a rigorous quality review with envelope engineers at Gale Associates. To streamline the foundation’s construction, we developed a Lean-inspired assembly-line process for the 232 concrete piles, working east to west. At any one time, we were driving piles, cutting them to required elevations and installing walers and cross-lot bracing to support the excavation,” Cammuso explained.

Next up: with the building’s underground levels almost complete, the installation of its innovative pre-fabricated structural system, The Infinity Structural System. The system will begin to be installed in August, bringing the Harrison Avenue project the benefits of pre-fabrication—shortening overall construction and creating a safer building environment by reducing work done on site. And, ideally, because the system is designed to reduce energy consumption, it will also reduce the building’s future operation costs.

Perfect for mid-rise buildings like the seven-story 600 Harrison, The Infinity Structural System combines the Epicore Multi-Story Residential (MSR) Composite Floor System with pre-panelized, load-bearing metal stud walls. Infinity Structures explains that Epicore’s floor system, which can clear span up to 27 feet, is “a two-inch deep, high performance long-span composite metal deck, which acts as a permanent form as well as the positive reinforcing within the slab.” It is uniquely suited for load-bearing metal studs because it inherently distributes loads evenly. Consigli’s team is coordinating the work of the four subcontractors installing the system.

When it opens in summer 2016, the new 600 Harrison block will add 160 rental apartments to the neighborhood’s housing stock, as well as 3,600 sq. ft. of street-level retail. Only a few steps from the South End Open Markets’ farmers’ market, arts market and food truck fiesta held every summer Sunday, this could be a pretty great place to call home.

Mastering 3D Chess on the Riverway: a New Residential High-Rise Takes Shape

RTHHeader

One of the city’s newest residential developments is rising up on Boston’s Riverway, the ribbon of Emerald Necklace park that runs past Longwood Medical Area. Underway with all the hustle you’d expect building next door to Brigham and Women’s Hospital—a major teaching and research hospital for Harvard Medical School—this project is the vision of Roxbury Tenants of Harvard, one of Mission Hill’s non-profit, neighborhood-controlled housing corporations. Brigham and Women’s, also a partner in the project, provided the land for the 11-story development. Come next summer, this edge of the Riverway will be 145 new high-rise homes, in a split of affordable rental units and affordable and market-rate condos.

Given Longwood’s status as the city’s second largest employment area with its 21 health care, research and education institutions—not to mention the dense Mission Hill residential neighborhood it adjoins—it isn’t surprising that managing a 160,000 sq. ft. construction project here is a lot like a 3D chess game.

From the get-go, the project’s been all go. The first step, transforming this urban site into one with a solid soil-base for the building’s foundation. Beginning February 26, over just 17 days (and some of them very snowy days), the team completed the soil-stabilization process required before the foundation work could begin, installing the site’s 790 rammed-aggregate piers (RAPs), at a rapid pace of 50 piers per day. Actually looking a lot like a chess board, this grid of 20-foot-deep piers, created a dense soil-base and prepared the way for the building’s spread-footing and slab-on-grade foundation.

Fast forward to June and the building’s 11-story concrete elevator and stair tower has risen up a floor a day and the site’s biggest chess piece—its 165-foot tower crane—has now taken up residence, ready to begin structural steel erection.

And if preparing a building’s strong foundation on a tight urban site is a game of 3D chess, then Consigli’s project team is a team of 3D chess masters. As Jay Rodriguez, Consigli’s Project Superintendent, describes it, “At any given moment, we are simultaneously coordinating the site access we share with the project being built next door, placing concrete, staging the next piece of work and making sure construction deliveries get in and out quickly while bypassing the nearby residential streets. It’s about managing each moment and knowing what the next series of moves needs to be.”

As a project with many stakeholders, it’s also not surprising that strong communication is as important as its strong foundation. Building at this crossroads of Longwood, Mission Hill and the Emerald Necklace for non-profit project owner, Roxbury Tenants of Harvard, Consigli’s on-going coordination with project participants includes the Boston Redevelopment Authority, the Boston Civic Design Commission, The City of Boston’s Department of Neighborhood Development, the Boston Residents Jobs Policy Program, the Massachusetts’s Department of Conservation and Recreation and the Medical Academic and Scientific Community Organization (MASCO), the 24-member non-profit dedicated to enhancing the Longwood Medical Area for all those who live, work, study or receive care here. Project communications vary from weekly community newsletters, prepared by the projects field staff, to monthly coordination meetings held at MASCO’s Longwood Ave property, where all contractors who are working in the neighborhood meet to review logistics and schedule as it relates to community impacts.

To plan the project’s next moves and keep its pace at its most efficient, the team uses Lean project delivery techniques including pull-planning, daily stand-up meetings and road block tracking. During these meetings, Consigli’s team and the project’s sub-contractors review upcoming work in six-week “look-ahead” increments so the team can assure work is ready to be performed on schedule. From fine-tuning upcoming steel deliveries, to managing the City’s approval process of the building’s full-scale exterior mock-up, these look-ahead schedules are micro-management at its best.

Heading toward its summer 2016 opening, each day brings the team and the project’s future residents closer to “checkmate.”