The new main branch of the Salt Lake City Public Library houses more
than half a million books. It also houses a number of features not
often found in a traditional library. They include everything from cozy
cafes to spiraling staircases.
Designed by the internationally known architectural firm of Moshe
Safdie and Associates, the new 240,000-square-foot facility houses a
number of non-traditional architectural features as well. Included
among them is a 4,000-square-foot, free-floating, undulating drywall
ceiling that dominates a circular 300-seat auditorium.
The ceiling is unique not only because of its stunning visual, but also
because of the method used to frame it out. Instead of traditional hat
track and carrying channel, a drywall grid system was used. The result
was a complex ceiling that was framed in half the time as more
conventional construction methods.
Auditorium Ceiling Has Potato Chip Contour
Spacecon West, a Salt Lake City contracting firm that provides metal
stud framing, drywall installation, acoustical ceiling installation and
variety of other services, installed the ceiling in the auditorium as
well as the ceilings in many other spaces throughout the facility.
Gary Hatch, the project superintendent on the job, explains that in
order to obtain the desired acoustics in the auditorium, the architects
designed an undulating drywall ceiling profile that his crews nicknamed
the “potato chip.” He notes the ceiling installation was difficult
because of the need to follow the unusual contour: “Making things even
more difficult was the fact that it was not one continuous ceiling. It
was comprised of seven individual sections of varying widths and
lengths separated by a 6- to 12-inch gap between them. There is also a
gap around the perimeter of the room, so the outside edge of the
ceiling never touches the wall. As a result, we had to suspend the
entire ceiling.”
The ceiling sections run parallel to each other like wind-blown ribbons
from the back of the auditorium to the front. And, because the space is
circular, the lengths of the sections differ, ranging from about 30
feet on the ends to nearly 150 feet in the middle.
Drywall Grid System Simplifies Curves
When it came to framing the unusual ceiling, Hatch notes that the firm
originally considered using the traditional method of cold rolled steel
carrying channels and hat tracks. But then, he began thinking about the
possibility of a drywall grid system instead. “We had used the
Armstrong Drywall Grid System before and were impressed with the speed
with which it goes up and the ease with which curves are created,” he
says.
The lightweight system is suspended from above using hanger wires like
an acoustical ceiling grid system. Its main beams and cross tees have a
wide one and a half-inch knurled face that allows easy installation of
screw-applied gypsum wallboard by reducing screw skate. They also are
rotary-stitched, providing extra torsional strength and stability by
reducing twisting of the components when the screws are attached.
“Since we had some limited experience with the drywall grid system and
a lot of experience with acoustical ceilings, it just made sense to
investigate this alternative. We eventually decided it was a good idea,
and now we’re really glad we tried it,” Hatch says.
Hatch notes that his previous experience with drywall grid was with
barrel vaults, where the radii of the curved elements were all
identical. “I had never been involved in a drywall grid project where
we had to follow a contour as intricate as this and where so many
different radii had to be formed. However, everything worked well,” he
says.
According to Hatch, the ability to pre-form the curved main beams on
the ground was key. “Once we created the curves, it was just a matter
of snapping the components together,” he notes. “Compared to track and
channel methods, the drywall grid system was at least 50 percent
faster.”
Not only was Hatch impressed with the speed of installation, but also
with the speed with which the crews learned the installation process.
“Many of the technicians on this job were very experienced framers,” he
says. “And, there is sometimes a tendency by journeymen to resist
change because it feels like they’re apprentices again. But once they
were taught the tricks of the trade, they all saw the benefits of the
system and became very proficient at its installation in a very short
amount of time.”
Undulating Ceiling Duplicated in Lobby
The same undulating ceiling visual in the auditorium is duplicated in
the lobby located outside a series of small meeting rooms. “The
architects wanted the same look so that when people attending a large
general session in the auditorium broke up into smaller groups in the
meeting rooms, there would be some continuity in the spaces.”
Hatch notes that this ceiling is much smaller in scale, with the
parallel ribbon sections running only about 30 feet in length rather
than 150 feet. But, framing the ceiling was once again complicated
mainly because the lobby is crescent shaped.
“If it were rectangular, it would have been much easier,” he says.
“However, the drywall grid system once again made the installation much
quicker. As in the case of the auditorium, we could have used
conventional track and channel construction here, but it would have
been a lot harder and taken a lot longer.”
System Used for Exterior Stucco Ceiling
The drywall grid system was used in exterior applications as well,
including a long stucco ceiling located under a walkway that leads to a
roof garden. “Once again, we could have used cold rolled steel and hat
track to frame it out,” Hatch says, “which is what the stucco
contractor expected because it was the traditional way of doing it.
However, we used the drywall grid system again because it was much
easier. “As far as the finished job was concerned, the stucco crews
couldn’t tell which framing method was used, traditional or drywall
grid,” he continues. “As long as we gave them a good, sound base on
which to attach their stucco, they were fine. So, while it may not have
made any difference to them, it made a big difference to us because the
drywall grid system went up a lot quicker.”
Speed, Versatility Are Biggest Benefits
In total, nearly 51,000 square feet of drywall ceilings were installed
on a drywall grid system throughout the interior and exterior of the
facility.
Reflecting on the entire project, Hatch describes it as “one of our
toughest, if not the toughest, jobs ever. From the installation of the
‘potato chip’ ceiling in the auditorium to the installation of the
football-shaped ceiling that soars five floors above the children’s
section, the library was a challenge. However, now that it’s completed,
it’s one of our crown jewels.”
About the Author
Dave Lewandowski is a free-lance writer based in Philadelphia who specializes in writing for the construction industry.
