Energy efficiency has become such a common goal for new construction these days that it’s easy to forget that not every building is perfectly made, and that fixing problems that reduce a building’s efficiency after the construction work is mostly completed can be an expensive, lengthy process.
The Department of Energy estimates that hat 85% of buildings in the U.S. lose 30% to 40% of treated air through duct leaks, which can result in sizable energy costs, ventilation systems that don’t work, and mold and mildew problems.
Hyundai faced this very issue only weeks before the January 2014 scheduled opening of its $200 million, 500,000-sf, six-story U.S. headquarters in Fountain Valley, Calif. That opening was in danger of being delayed for months when excessive leaks were discovered in the structure’s four smoke evacuation shafts and outside air shaft.
Brian Berg, an associate principal with Glumac, the project’s Engineer of Record, notes that the building’s design posed some major challenges. The architect, Gensler, had specified that it didn’t want structural beams in any of the building’s usable space. So where to put those beams was left to the mechanical engineering team.
The decision was made to run beams and conduit through the building’s 8- by 6-foot shafts, which doubled as the building’s air ventilation system because the structure had been designed with no sheet-metal air ducts.
However, all of that metal running through the shafts inevitably poked some holes in them. In addition, not all of the joints in the shafts had been sealed properly. Testing determined that 14,861 cubic-feet-per-minute of air was leaking, or about 20%, well in excess of the 5% limit allowed by building codes.
“The supervisor on the Building Team was pretty tough,” wasn’t going to sign off on this project until the leakage problem was rectified, recalls Bob Evans, Hyundai’s Senior Project Manager. (Hyundai Amco America was the project’s GC.)
Hyundai shows how the sealant is injected into the shafts. Photo courtesy Hyundai
One solution considered was to build scaffolding inside each shaft in order to seal visible leaks in the interior fiberglass drywall by spraying those walls with rubberized foam. However, that process would have cost up to $1 million and would take months to complete.
Berg says he reached out to Glumac’s other offices around the country, and heard back from its Las Vegas office, which had just solved a leakage problem in a new city center it was working on by using a technology called aeroseal, which seals leaks from the inside of pressurized ductwork.
This product has been around since the mid 1990s, and its development funding had been sponsored by the Department of Energy. Evans says he had heard about it, but thought it was “like snake oil; you know, too good to be true.” But he did some research and found that aeroseal had been effective in sealing bricks and mortar buildings.
AWC, a certified aeroseal contractor, came on board and took a couple of weeks to complete the shafts, at a cost that Evans estimates was less than $150,000. The Building Team opened walls on at least one floor to conduct testing, and found that the leakage had fallen to 808 CFM, or less than 1.1%. A bonus, says Evans, is that the aeroseal sealed around the electrical plates and boxes, too.
The headquarters building was completed on time and opened on schedule. Berg says he’s been recommending aeroseal for other projects ever since, especially for existing buildings that can have a lot of leakage over time but would be difficult to fix.
This is what the shafts look like after the sealant is injected. Photo courtesy Hyundai
A tool measuring the air leakage after the shafts were sealed (less than 1%). Photo courtesy Hyundai
Related Stories
| Apr 24, 2012
AECOM design and engineering team realizes NASA vision for Sustainability Base
LEED Platinum facility opens at NASA Ames Research Center at California’s Moffett Field.
| Apr 23, 2012
Innovative engineering behind BIG’s Vancouver Tower
Buro Happold’s structural design supports the top-heavy, complex building in a high seismic zone; engineers are using BIM technology to design a concrete structure with post-tensioned walls.
| Apr 20, 2012
McCarthy completes Santa Barbara Cottage Hospital Replacement Facility
The new hospital’s architectural design combines traditional Santa Barbara Spanish colonial architecture with 21st century medical conveniences highlighted by a therapeutic and sustainable atmosphere.
| Apr 20, 2012
Century-old courthouse renovated for Delaware law firm offices
To account for future expansion, Francis Cauffman developed a plan to accommodate the addition of an 8-story tower to the building.
| Apr 20, 2012
Registration open for Solar Power International 2012 in Orlando
President Bill Clinton to deliver keynote address at ?largest solar energy event in the Americas.
| Apr 19, 2012
KTGY Group’s Arista Uptown Apartments in Broomfield, Colo. completed
First of eight buildings highlights unique amenities.
| Apr 19, 2012
Nauset begins work on $20M Joint Forces HQ at Hanscom AFB
3D imaging key to project timetable and cost containment.
| Apr 18, 2012
Lafarge moving North American headquarters to Illinois
Lafarge CEO John Stull says the factors in their decision were location in the Midwest and area transportation.
| Apr 18, 2012
Positive conditions persist for Architecture Billings Index
The AIA reported the March ABI score was 50.4, following a mark of 51.0 in February; greatest demand is for commercial building projects.
| Apr 17, 2012
Princeton Review releases “Guide to 322 Green Colleges”
The guide profiles 322 institutions of higher education in the U.S. and Canada that demonstrate notable commitments to sustainability in their academic offerings, campus infrastructure, activities and career preparation.
