New Crime Lab for Phoenix

by Scott Blair

Though the new Phoenix Forensic Crime Laboratory broke ground in July of 2005, the lab's design and construction documents were being finalized during some of the largest cost increases for materials the building required the most: steel, concrete, copper and petroleum products.

"We pretty much got hit with everything," said Nancy Crump, assistant crime lab administrator with the City of Phoenix Police Department. "We've had to evaluate the budget at every step in the process, as well as do a lot of value engineering."

Providence, R.I.-based Gilbane Building Company was brought in early through Phoenix's new construction manager at risk process which is required on all city-funded projects. "We had approximately $1.5 million of value engineering that was accepted on the project," said Todd McMillen, project manager with the contractor. "The original concept of the flooring was terrazzo, which is very high-end. Lab settings such as this typically react better to vinyl-type flooring." Sheet vinyl with welded seams was chosen as the primary flooring, saving approximately $400 thousand.

The $34.6 million project is currently 50 percent complete, and nearly three months ahead of schedule. Completion is anticipated by June of next year.

With three levels situated in an 'L' shape at the intersection of 7th Avenue and Jefferson Street, the 104,000-sq.-ft. lab will give the department more than five times their existing space. Lab space is housed on one wing, while office space occupies the other.

Height restrictions relating to the site's proximity to the Sandra Day O'Connor Federal Courthouse required the three-story structure to have the first floor completely below-grade. "It did allow us to get our program size into a smaller footprint and leave more of the site open for planting and trees," said Evan Sockalosky, designer of the project with the Phoenix office of architectural firm Durrant. >>

The green area will sit above a two-level underground parking structure comprised of pre-cast concrete. "Having a park-like setting on top of a parking structure creates a challenge with the size of trees and the amount you can get, and still drain the plaza in the correct way," Sockalosky said.

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The laboratory building is comprised of structural steel on spread footings with a slab-on-metal deck for the upper two stories. A mechanical penthouse houses the building's ample mechanical requirements, including air handler units, exhaust fans and boilers. A separate cooling tower is located on the southwest corner of the building.

"The lab exhaust system is a very critical requirement," McMillen said. "There are in the order of 50 combined fume hoods and bio-safety cabinets with very specific control and exhaust systems." The cabinets will use venturi valves, which are digitally-controlled, cone-shaped air valves with almost immediate response time.

The shape of the building is a result of the building's mechanical requirements. Since the labs needed single-pass air with 100 percent exhaust, creating two separate wings allowed for a more efficient layout of the mechanical systems, according to Sockalosky.

Another benefit to the shape was controlling the flow of evidence through the building. Evidence will be brought in through a secure vehicle checkpoint located on the lower level of the facility and placed into secure lockers. From there, 'wet' evidence that may contain bodily fluids is brought to a drying room with separate entry and exit points to avoid any introduction of contaminants.

Examination facilities include laboratories for photo analysis, latent prints, DNA testing, toxicology, controlled substances and forensics.

A firearm testing lab features a firing range for cartridge ejection and recovery analysis, and features sound attenuation and high air flow due to toxic lead released from the bullets.

There are also three vehicle examination bays in the lower level.

"As common with most crime labs, we have backlogs and limited resources," Crump said. "Moving into this new building should allow us to really attack that backlog once we are fully staffed. It's going to be infinitely better than what we are used to working in right now."

In May, the city granted a five-day road closure of one of Phoenix's busiest streets, 7th Avenue, to Gilbane so that the contractor could position a large crane and multiple tractor trailers in order to erect the exterior pre-cast concrete panels onto the building's west face.

Gilbane coordinated their subcontractors to be on the site 24 hours a day in staggered, back-to-back shifts. Each trade would hand off their work zone from one trade to the next as they completed their portion of the job. Phoenix-based Coreslab Structures was the concrete contractor while Buesing Corporation handled excavation. Other trades involved in the activity were barricade contractor Jones Concrete Construction, underground utility contractor Juarez Contracting and Progressive Roofing, all of Phoenix.

The erection was completed and the roadway re-opened 24 hours ahead of schedule. "It was a flawless orchestration of construction activities that were continuous during the entire 96 hours and completed safely," McMillen said.