Volume 49, Issue 3 - March 2014

The New Black

Companies Explore Opportunities in Commercial Window Projects
by Ellen Rogers

Commercial windows or curtainwall? It’s a question many builders, developers and architects ponder during the early design stages of a project. Which is right for a given application? Why might a builder opt for one type over the other? Whichever one a project may require or an architect specify, the answers are mixed as far as whether the market is leaning more toward the use of commercial windows or curtainwall.

Windows of Opportunity
As Paul Beers, managing member of Glazing Consultants International LLC in West Palm Beach, Fla., explains, the market for commercial windows is doing well. His firm has seen an increase in projects calling for windows, but doesn’t think it’s necessarily a trend.

“I think it’s been going on for some time. Schedule, budget, etc. often dictate using windows instead [of curtainwall],” says Beers.

Being located in South Florida, which is experiencing a construction boom, Beers says they’ve seen a lot more commercial windows used compared to curtainwall, even when the desired look is all glass.

“I think the perception is that [windows are] less expensive and easier to [work with]. So if you wanted an all glass façade you could do it with curtainwall or floor-to-ceiling windows,” says Beers, adding that in South Florida he rarely sees curtainwall on high-rise residential projects.

"One way to mitigate the high cost of field labor is to utilize pre-glazed products either window or curtainwall systems. This can also drive product and installation quality." —Jack Williams, EFCO

“In South Florida a lot of buildings are 50 stories and that would be a common application. Also, with window systems they are often ready to go as far as code approval and curtainwall [requires] more custom [work]. On large, massive projects [using curtainwall] is not an issue because mock-ups are already being done, etc., but on smaller projects [it’s easier] to take what’s already existing. These decisions are made very early in the design stage [during the] scope and budget phase.”

He adds that the decision surrounding which product to use might also weigh in on the contract glazing company and whether it’s comfortable with windows or curtainwall.

“A lot of times the glazier selected is one with which they [developers, architects, owners, etc.] already have a relationship. For some contractors [a particular product type] is their sweet spot.”

The type of construction might also be a determining factor.

“We are seeing the use of curtainwall far more frequently in new construction and the use of commercial windows more often in retrofit applications,” says Lisa Jackson, LEED AP, product manager, windows manager, sustainability for Kawneer Co. Inc. based in Norcross, Ga. “We are also seeing commercial windows being used more in high rise residential applications.” She adds that there are a number of benefits commercial windows can offer. “In addition to increased exposure to daylight on the interior of a building, as well as aesthetic benefits, commercial windows provide ventilation, which makes them ideal for schools and multi-family applications where occupant comfort is a critical factor.”

While some companies have seen the increase in commercial window demand, others see just the opposite. EFCO Corp. in Monett, Mo., for example, has historically focused on the window segment, which Jack Williams, director of product marketing, says makes up a bigger part of the company’s overall product sales.  

“In the past few years we have enjoyed significant growth in curtainwall so that is a positive trend for our business,” he says. “Additionally, the design intent of the building can play a large role in the decision to use a commercial window opposed to a curtainwall system. For instance, if the architect is looking for a lower window-to-wall ratio, or if the project has stringent thermal requirements then a window system would be favorable.”

Installation Tactics
When it comes to installation there are some differences in windows and curtainwall. For the most part, windows are installed from inside the building, while curtainwall is typically unitized, pre-fabricated and then lifted up from outside the building. In other words, window installations take place inside the building while curtainwall installation is from the outside.

“Most everything [curtainwall] is unitized,” says Beers. “If it’s stick built it’s usually a smaller application. Unitized products provide a better opportunity for quality and consistency.”

One point of interest Beers points out is that curtainwall material can, in many cases, be used for commercial windows.

“Particularly in high wind areas, curtainwall material is used frequently for windows because it has high performance with wind, water, etc.,” he says.

Jackson, likewise, says that typically curtainwalls are built and glazed onsite, adding they, too, are seeing an increase in unitized applications, which enable the curtainwall to be fabricated, assembled and glazed before it gets to the jobsite.”

So, do these job types require a different installer? Not according to these experts.

“Contract glaziers have [areas in which] they specialize and do well so typically it’s an either-or where a glazier promotes and pushes and designs around one product type or the other; typically but not always,” says Beers. “Some do both, but generally they favor one or the other.”

Jackson says her company’s products are installed by contract glaziers and can be glazed in the factory or in the shop or field, depending on the preference of the glazier or installer.

“The field-glazed option will increase labor time on the job site, while a factory-glazed option will reduce labor in the field,” she says.

She adds that her company has a vertically integrated manufacturing process for commercial windows, “so we are able to provide the product fully factory assembled and glazed, which allows the windows to be installed quickly in the field. This also greatly enhances the quality of the product compared to site-built systems. Our systems are fabricated, assembled and glazed in a controlled environment with automated manufacturing technologies and in-house testing.”

Speaking of window installation, Williams explains that the process typically involves installing a factory-glazed window by either sliding a window into a subframe or panning system and applying a closure to lock the window in place, by mechanically fastening the window to the condition through the frame or by attaching an anchor to the window frame.  

“For curtainwall, there are a multitude of options,” he says. “On one end of the spectrum we have customers who take lineal sticks and install verticals, horizontals, and glaze completely at the jobs site. On the other end of the spectrum, we have customers who order assembled unitized panels, and the only installation done at the job site are the panels.”

He continues, “For all installations you will have anchorage and sealing requirements at the job site. One way to mitigate the high cost of field labor is to utilize pre-glazed products either window or curtainwall systems. This can also drive product and installation quality.”

But whether windows or curtainwall, Williams points to one key concern among installers.

“One challenge I consistently hear from our customers is the difficulty in finding qualified field labor,” says Williams. “I think this will continue to be a challenge regardless of commercial window or curtainwall growth.”

The good news, though, for all those involved, from suppliers to installers, is that the market is improving. Beers explains, window suppliers survived the downturn fairly well with retrofit work and are now thriving. “The curtainwall guys had some failures during the down time, but there is more work now and they, too, have kept up with technology [with] quality systems. It’s now a better time for everyone and there is a place for everyone in the market.”


Chinese Imports: Less of an Issue for Commercial Windows
One challenge the curtainwall industry has faced involves the importation of aluminum extrusions into the U.S. from China (see related article on page 28). The commercial window market, however, has not felt this same burden. Lisa Jackson, LEED AP, product manager, windows manager, sustainability for Kawneer Co. Inc., says at her company they have not seen the commercial window market affected by imports.

“It is important to note that rigorous testing and many different hardware options are required,” she says. “The commercial window market can require several varying installation requirements thus there is a large need to provide project specific solutions for surround conditions.”

Jack Williams, director of product marketing, for EFCO Corp., agrees and says his company also has not felt an impact when it comes to commercial windows.

“I think the logistical challenges have been difficult to overcome,” he says. “If you are installing a ribbon window system and you damage a window, would you rather get the replacement window from Missouri or China?”

Tall Tales
Over the past few years the construction industry certainly saw its share of stalled projects. Plans to build big were put on hold. This slowdown left the U.S. with few newly constructed tall buildings. So what impact did this have on the use of windows verses curtainwall?

“There is no doubt that the economic downturn was a blow to the industry,” says Jack Williams, director of product marketing, for EFCO Corp. “With fewer private dollars available for construction we did see a decline in some of the taller buildings. At least from our standpoint, I would not say that windows or curtainwall were more impacted or that one became preferable during this time.”

Lisa Jackson, LEED AP, product manager, windows manager, sustainability for Kawneer Co. Inc., adds that curtainwalls are still predominantly used on high-rise applications. “The trend we have seen is that exterior fenestration walls have migrated from full vertical curtainwalls to punched opening or slab-to-slab type applications, which are more suited for commercial window products.”

In Miami, however, Paul Beers, managing member of Glazing Consultants International LLC, says there has been no shortage of tall building construction lately.

“Most of our projects there are really tall buildings [and are using] windows,” he says Beers points out, though, that the size of the structure isn’t what determines whether windows or curtainwall are the best fit. “It’s more about the design concept than the size/shape of the building; a five-story commercial building could have an all glass facade and be built with curtainwall.”

Ellen Rogers is the editor of USGlass magazine. Follow her on Twitter @USGlass and like USGlass on Facebook to receive updates.

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