Features: What We Build — May/June 2007

Streamline Tower Plays Las Vegas

The soaring Streamline Tower, a new 275-unit luxury residential high-rise, is helping reshape the downtown Las Vegas skyline

by Tony Illia

The Streamline Tower rests atop a 10-ft-thick reinforced mat foundation consisting of 7,000 cu yd of concrete provided by Rinker Materials Corp. and placed by Martin-Harris Construction. Photo courtesy of Martin-Harris Construction

The streamline tower is the newest act to play downtown Las Vegas. The $150-million, 21-story mixed-use building will consist of 275 luxury condominiums with 12,000 sq ft of commercial retail space. The project, developed by Barclays North Inc. of Everett, Wash., is located on a one-acre parcel with zero lot lines at the southeast corner of Ogden Avenue and Las Vegas Boulevard.

The property, which once contained the 70-room, two-level Golden Inn Motel, was purchased for $6.4 million in June 2004. NU Equipment Inc. of north Las Vegas, demolished the aging two-building motel.

The new 271-ft-tall Streamline Tower will be the first residential high-rise inside the city’s Entertainment District—a three-year-old, six-block development overlay created to attract new investment dollars to downtown’s aging business core. It will also be downtown’s second-tallest tower upon completion—behind the 360-ft Fitzgeralds Casino & Hotel.
“We’re really starting to see the Entertainment District become a thriving part of downtown,” says Las Vegas Mayor Oscar B. Goodman, who has made revitalizing downtown a priority since taking office in 1999.

Lucky Numbers

Streamline broke ground in May 2006, with general contractor and AGC Las Vegas Chapter-member Martin-Harris Construction facing site constraints, an aggressive schedule and a unique design. The 30-year-old, Las Vegas-based firm has a $107-million, guaranteed-maximum-price construction contract, with a 660-working-day schedule that carries $5,000 a day in early completion bonuses and/or late penalties.
The project currently is on track and scheduled to finish Feb. 14, with added time allowed for owner scope-of-work changes. (For example, the building interior was reconfigured to create additional condominium units.)

Houston-based PGAL LLC is the project architect and contract administrator. Corus Bank of Chicago is providing the $123-million project construction loan, with mezzanine financing from MMA/Transwestern Mezzanine Realty Partners, New York.

The brownfield site required roughly $2 million of utility upgrades over six months in 2004, including demolition of two buildings and one mile of difficult electrical-power trenching through city streets and caliche soil. The building’s 43,000-sq-ft footprint consumes the site, leaving no space for storage or staging. The developer is renting 1.5 acres across the street for construction operations.

The high-rise rests atop a 10-ft-thick reinforced foundation mat that slopes from 11 ft to 17 ft below-grade in order to avoid the water table. The foundation entailed a 14-hour continuous pour with five pumps and 80 mixer trucks delivering 7,000 cu yd of concrete provided by West Palm Beach, Fla.-based Rinker Materials Corp.

The 621,000-sq-ft, cast-in-place horseshoe-shaped tower features 8-in.-thick post-tensioned floors.
Streamline will consist of street-level shops below a six-level, 428-space parking garage with one-, two- and three-bedroom residences above. The project’s condominiums, which range from 768 sq ft to 1,999 sq ft in size, are reportedly 60% sold out, with asking prices of $356,000 up to $1.3 million.

Streamline has no floors or units numbered “four” because the word four is read as “si” in Chinese Mandarin and “shi” in Japanese, close homonyms for the word for death in both languages. It traditionally lacks a level 13, a bad-luck number.

But lucky Streamline homeowners can enjoy several luxury amenities, including a 1,500-sq-ft fitness center, clubhouse, two meeting rooms with a big-screen TV and kitchen, and a rooftop swimming pool with an open-air, landscaped terrace.

Construction Innovation

Streamline also has some innovative building solutions. For example, hand-set concrete forms were used because there was no room for flying forms or a gang system, which typically needs less labor. As a result, Streamline will see up to 700 tradesmen on-site during the height of construction.

The 271-ft-tall Streamline Tower uses cast-in-place construction with post-tensioned decks and hand-set concrete forms because site constraints did not allow for flying forms or a gang system. Courtesy of Martin-Harris Construction

The tower is rising at a rate of one floor every six days. Martin-Harris achieves this pace by breaking the building into two work zones, while applying a chemical additive to the concrete that reduces cure time from seven to two days. (Concrete must achieve 70% of its final strength before removing post-tension cables.)

“We schedule concrete deliveries months in advance so trucks can travel through downtown uninterrupted,” says Craig Colligan, Martin-Harris senior project manager.

Each floor contains roughly 400 cu yd of 5,000-psi to 6,000-psi concrete. Streamline will use a total of 38,000 cu yd of concrete, 2,560 tons of supporting steel and 1,576,400 ft of post-tensioning cables.

Weekly preplanning meetings between the architect, contractor and owner have kept the construction progress smooth. “We went from a table-napkin sketch to construction drawings in 10 months,” says Dusty Allen, Streamline’s managing member. “The cooperation between general contractor, architect and developer has really helped move the process along.”

Streamline similarly relies on select pieces of heavy machinery working together to aid vertical construction, including a hammerhead tower crane that runs through one of the building’s three elevator corridors and a crawler crane across the street.

The project received city approval to swing building materials overhead across a 30-ft section of Ogden Avenue, provided flagmen stop traffic first. Martin-Harris also uses 120-ft-long mobile scaffolding that moves at 7 ft per minute, enabling workmen and materials to rise and drop alongside the building with elevator-like convenience.

The building skeleton is made up of six 18-in.-thick shear walls that carry the lateral load, along with 2-ft-sq supporting columns spaced 28 ft apart per each floor plate.

Level two features two 36-in.-wide, 132-in.-deep, 52-ft-span post-tensioned girders that transfer the building load to create a roomy double-height ground-level area for delivery trucks as well as a glass-encased retail colonnade. There is also a third 33-in.-wide, 70-in.-deep, 52-ft-span transfer girder.

The building’s concave design maximizes the number of units along its southern exposure, which overlooks the Strip. The horseshoe-shaped, asymmetrical high-rise has open-air balconies for 90% of its residences. Some upper floor plates cantilever by up to 11 ft.

The façade is a combination of an aluminum-framed, low-energy glass curtain wall and stucco, with animated street-level neon signage for retail shops. “We basically wanted to make it a simple urban design, working off the streamline theme,” says Rick Van Diepen, PGAL’s project manager.