Volume 42, Issue 9 - September 2007
People Who Live In Glass Houses …
Learn Lots About Glass Replacement
There’s a saying about people who live in glass houses. No, not that one. Something to the effect of: “Architecture should move you, amuse you, inspire you.” Actually, that’s a saying from one person who lived in a very recognizable glass house.
Architect Philip Johnson built his glass house in New Canaan, Conn., in 1949. The house was constructed using lites of ¼-inch glass, divided and supported by black steel pillars, with no interior walls. The house, which Johnson considered a “viewing platform” of the surrounding landscape, is now known as a textbook example of architectural modernism. It has been back in the spotlight in recent months since it opened to the public for the first time in its 50-plus year history (see The Story of the Glass House). While tours have been conducted since April, the site, now under the care of the National Trust for Historic Preservation, will close late next year as it is prepared for a major renovation next winter, including the replacement of that famous glass.
The Look that Needs to be Preserved
“As years went by, the extreme oversize of the glass really dictated something stronger in there, and I think the next step was to temper ¼-inch glass,” says Paqua. “That proved to be pretty problematic … because of the waves in [tempered glass].”
Paqua says the next step was to turn to 3⁄8-inch clear tempered glass, “and that seemed to solve most of the problems.”
“Replacements have been ¼-inch tempered (2001 and 2004 replacements), ¼-inch laminated (2000 and 2002 replacements) and 3⁄8-inch tempered (1999 replacement),” elaborates Sandy Cross, Glass House preservationist. “Laminated or tempered safety glass was chosen for replacements, rather than plate glass, due to contemporary building codes.”
Cross says the glass has been replaced on an as-needed basis, and, according to Paqua, it’s been needed frequently.
“Franklin Glass installed the original glass in the house and we’ve pretty much been servicing that place since 1949,” Paqua says. “Over the years we’ve pretty much replaced all of the glass in the house.”
Expecting the challenges of living in a glass house, Johnson convinced PPG to keep the original, large lites used for the house in stock in case of glass breakage, Paqua says. “Today, getting these oversized lites is not [as much of] an issue as it used to be,” he adds.
According to a 1996 Conditions Survey Report by Philip Johnson, Ritchie and Fiore Architects, availability played a big role in the choice of whether to use laminated or tempered glass for replacements. “Tempered glass is ordered to size, while laminated glass can be cut to size and fabricated in the shop,” says the report.
The framing system is all steel, including mullions and transoms, with stops for the glass infill. The original glass had been set in glazing putty, Cross says, although replacements have been set with pre-shim Tremco tape and sealed with either silicone or polyurethane sealant.
With all the glass breakage that has occurred over the years, it is the steel framing system that is behind this latest renovation, which will replace all of the Glass House’s famous cladding.
“The corrosion of the steel (severe in several locations) was contributing not only to the degradation of the steel itself, but also was affecting the glass—the glass is cracked in a few areas due to the pressure placed on it by the expansion of the steel caused by oxide jacking,” Cross says.
The renovation will aim to prevent moisture infiltration problems, which has led to much of the deterioration.
“The original steel transoms are flat and there are no weeps at the stops, so moisture ponds on the surface … additionally, much of the sealant, until recently, was cracked, deteriorating and missing,” Cross says. “If the moisture infiltration issue is not mitigated, then deterioration will continue and the restoration project will be all for naught.”
The Modern Overhaul
While there have been countless innovations in glass since 1949, from increased energy efficiency to security (see What if the Glass House was Built Today), the main concern with the renovation is to maintain the original design intent of the Glass House. “We do not want to alter the way the Glass House looks due to a change in glass type or thickness, nor do we want to affect the way the landscape is viewed from the inside of the Glass House looking out,” Cross says. “We merely want to maintain the building and make it safer for the public. If we took no action, the steel would continue to corrode, the brick would continue to spall and the glass would continue to crack.”
Oldcastle Glass, headquartered in Santa Monica, Calif., will provide the glass. According to Mary Carol Witry, vice president of business development for Oldcastle, there will be some further changes to the type of glass used in the house.
“It’s going to be annealed, laminated glass,” Witry says. “We’re going to need to increase the thickness because of the updated codes.” Until further studies of the building are undertaken and a design architect is brought on board, specific dimensions will not be determined.
“A minimum of 3⁄8 inches thick overall, maybe as much as ½-inch,” Witry says.
What to Expect
“We’ll be able to maintain the original intent of the building,” Witry says.
“We went out there and looked at the existing framing and stops to ensure that we’re not going to have to change any profiles so, aesthetically, the look will be there—clear glass is clear glass.”
While product choice won’t be a problem, the logistics of installation may be.
“Logistics of getting to the actual house is a concern,” Witry says. “There’s quite a beautiful landscape around, and special care needs to be taken into consideration. There’s a long way to travel to get the glass into the opening.”
Paqua recalls, “When Mr. Johnson was alive [glass replacement] was very difficult because he wouldn’t want us to step on the lawn.”
However, Paqua says the biggest challenge he’s faced in replacing the glass involves removing the screws. Over the years, though, the materials have changed and the current use of stainless steel screws has eased that challenge.
Since the renovation is still in the early stages, a glazing contractor has not yet been chosen to perform the work. The renovation is expected to take place between fall 2008 and spring 2009, and the National Trust staff hopes the project will be completed prior to the start of the tourist season in May 2009.
“We will begin the restoration in fall 2008—the tour season will end early for this reason—and will continue through the winter and spring, so no visitors will be onsite during the time of the project,” Cross says.
The Story of the Glass House
Johnson is known for having designed some of America’s greatest landmarks, most notably his own home, the Glass House. Regarded as one of the world’s iconic, mid-century modernist structures, the Philip Johnson Glass House began in 1949 as a five-acre parcel of land containing the Glass House, Brick House and connecting courtyard. The site has grown over the course of nearly 50 years, and stands today as a 47-acre canvas. Johnson built the Glass House as his private residence, and used it continuously until his death in 2005. Its purpose was to provide a vantage point on the landscape.
Johnson interchangeably referred to the entire site including the house as “the Glass House.” The site encompasses 14 structures—11 structures designed by Johnson and three vernacular structures original to the property and renovated by Johnson and his partner, David Whitney. These buildings provided the context for many daily activities at the Glass House.
“He was a wonderful guy to work with and I met him on numerous occasions,” says Dave Paqua, president and owner of Franklin Glass and Aluminum in Stamford, Conn. Paqua’s father did the original glass installation for the Glass House, and Paqua has assisted with periodic glass replacements. “He was fun to talk to and truly loved the place.”
Paqua, who has spent much time on the grounds of the Glass House, says that to see the house is to understand how a person could make it a home.
“You have to see how you could absolutely, without question, live in this house,” says Paqua. “The views in and out and the landscaping and the vision that he had are absolutely outstanding.”
What if the Glass House was Built Today?
“As an architect, Philip Johnson was said to favor aesthetics over function, and his iconic Glass House is likely the starkest and most visible expression of that sentiment,” notes Robert J. Struble, marketing communications manager for PPG Industries Inc. in Pittsburgh. “Fortunately, over the past 60 years since the Glass House was constructed, numerous advances in glass have largely eliminated the gap between its obvious aesthetic appeal and its impracticalities as a building material (solar heart gain, lack of insulation).”
Lack of insulation was a problem that Johnson didn’t try to solve. According to Dave Paqua, president and owner of Franklin Glass and Aluminum in Stamford, Conn., Johnson’s solution to the cold Connecticut winters was to stay in the Brick House once the temperatures dropped. “You can’t live in the Northeast today and not have insulating glass (IG),” says Paqua.
Owners of 10 to 15 other “glass houses” in New Canaan, Conn., have already had Paqua re-glaze their walls with IG.
“It should be double-glazed with a low-E coating for insulation and heat loss,” recommends Chris Barry, director of technical services for Pilkington in Toledo, Ohio. Barry says an appropriate low-E coating and/or window tint could be used to control the glare as well as the heat gain. “There’s a million and one of those available.”
Scott Thomsen, chief technical officer and vice president of Guardian Group, would solve the problem of cold winters another way: heated glass.
“We take the IG unit and we apply a special coating, we apply voltage and the IG emits heat inside the house,” Thomsen says. “It increases the creature comfort.”
To stop the loss of heat from the home, Struble suggests PPG’s Solarban 70XL transparent solar control low-E glass. “The aesthetic and environmental benefits of Solarban 70XL glass are reflected most clearly in its light to solar gain (LSG) ratio, which measures 2.37 in a standard 1-inch IG unit.”
Thomsen says he would suggest using laminated glass to solve an altogether different problem. “[You] need to either use vacuum IG or laminated to reduce the sound.”
As Thomsen notes, most houses use gypsum board and fiberglass insulation for soundproofing, while a glass house wouldn’t have those luxuries. Laminated glass would help to dampen the noise outside.
Thomsen says laminated glass isn’t necessary, though, for another problem for which the Glass House is known. As Paqua knows from his many trips to replace glass in Johnson’s house, birds flying into the windows can be a big problem. Paqua recalls that it seemed to always happen during a company Christmas party that he would get a phone call from Johnson or the Glass House caretaker that a goose had gone through one of the windows.
“The bird … thinks there is more area behind the glass and flies on into it,” Barry explains. “To effectively prevent that from happening, the window needs to be broken up into smaller frames or [use] a silkscreen on the glass.”
That’s not an option for the Glass House, where visibility is key. But, as Thomsen says, this is not a problem that’s unique to this glass building.
“There are actually some cities that are enacting codes right now that you need to have something in the glass that birds see. There’s research being done that birds can see in the ultraviolet (UV) region,” Thomsen says. “There’s work being done in Chicago, New York and London to put coatings on the glass that birds can see in the UV range, so birds won’t run into the glass.”
If, rather than glass breakage, smudges are the concern, Barry has a suggestion for that as well. “The ‘self-cleaning’ coating is an interesting thing to consider for a situation like that,” he says. Barry also suggests an anti-reflective coating to allow for transparency in the modernist monument, “to allow people to see in more readily.”
Another problem with living in a glass house is that the furniture is sure to fade from constant exposure to UV light.
“Laminated will block the UV—or we have a product called ClimaGuard SPF that blocks 99.9 percent of UV,” Thomsen says.
Whatever the choice of glass product, Struble says, it would ultimately have to be energy-efficient. “[Johnson] seemed to care about those things long before it was in vogue,” he says.
And whatever glass products were used, the glazier on the job would have his run of a fascinating site dedicated to his medium.
“It would be pretty exciting to do,” says Paqua.