Revolutionizing an Industry
New Technology is Changing the Way Vinyl Windows are Made
by Alan B. Goldberg

The window-making operation at Window Shapes Inc. in Union, N.J., is anything but traditional or standard. The company, which specializes in custom shapes, said it is one of the nation’s largest providers of specialty windows. “If you can dream it, we can do it,” are the words in its promotional brochure. But there is more to its statement, “we’re shaping the custom window business into a more exciting and responsive industry,” than the types of windows it produces. Window Shapes is about to change the way it manufactures (one of its products) by incorporating a new technology that could impact an entire industry.

The Sashlite Technology

It began with a simple concept. Rather than improve an existing product or process in the manufacture of vinyl windows, why not find a way to simplify what has become a more sophisticated and automated operation. A seasoned executive does just that and conceives of an idea that leads to a new technology, a new venture and a change in direction.

Integrating a spacer directly into the sash profile and changing the way insulating glass has been manufactured seemed to be a logical step for John France who has spent 20 years in the manufacture of windows and doors. France couples his expertise with Bob Hornung’s entrepreneurial success in developing commercial technologies and in 1999 they form Sashlite LLC of Westport, Conn., to develop, market and license the innovative technology as president and vice president, respectively.

“We’re streamlining the whole manufacturing process. We’re taking spacer and insulating glass (IG) production and bringing everything right to the sash,” said France. Hornung refers to it as a hybrid between backbedding and the insulating glass process.

According to Hornung, Sashlite is expected to become a technology of choice because of the significant cost savings in time, labor and space that can be realized. It is “simple in nature and concept,” he said. The manufacturing process is described this way: extruded insulated sash is cut to the required lengths; these are welded into a solid frame; desiccant is applied; the muntin grid is assembled and attached to the frame; sealant is applied; lites are adhered to each side of the sash; and glazing beads are attached. Two simple illustrations show how Sashlite eliminates an entire assembly process. In the traditional method (A), an insulating glass unit is made and then attached to a sash unit with sealant or tape. With Sashlite, instead of this two-step process, Hornung said, an “insulated sash” is created by directly applying two lites of glass to the sash unit.


Hornung sees many advantages over other systems. One of the most important, he said, is cost.

“Because it is a simpler product to make, there is less to do. Windows can be produced in less space and fewer things can go wrong and that translates into lower assembly and product costs, lower inventory and overhead costs.”

Sashlite is also the first technology that can be incorporated into any size operation and provide cost savings to a manufacturer, regardless of volume. We have detailed information that compares direct labor and direct material costs and manufacturing costs to other systems,” he added.

Another attractive feature is the minimal investment. Since manufacturers will already have the necessary equipment—fabrication units—they only need an upgraded glazing table and possibly an additional washer. While the cost can vary, it is not considered a significant investment.

Hornung said Sashlite is the “only technology that combines higher warm-edge performance, greater efficiencies in manufacturing and improved aesthetics.” He attributes the warm-edge performance to the vinyl spacer. And the aesthetics, he points out, come from cleaner sight lines. One lite of glass is easier to handle than an IG unit. It is much easier to lay down and it centers itself.

“The result is perfect 90-degree corners with no unsightly interruptions in the viewing perimeter,” said Hornung.

Grid alignment is easier, he said, because the grid is attached to the sash. By having the spacer automatically notched in key locations, inserting the muntin clips and squaring the grid is much simpler.

The process does not depend on batch processing, Hornung adds, so changes can be made on the line without disrupting the operation. It also makes it possible to change the glass thickness—to laminated or safety glass—because only one profile is being used.

Referring to the flexibility of the technology, Hornung believes this is another significant advantage.

Fast Stats: Bob Hornung

Bob Hornung, (at left, in photo with Tom Change of Window Shapes), president of Sashlite, LLC, founded the company in 1999. He is also managing director of Vertical Ventures, LLC, a venture capital firm that specializes in funding and managing early-stage companies.

If the success of other companies Hornung has been involved with is any indicator, Sashlite is in good hands. For example, Hornung founded On-Link, a business application software company and the first network of its kind to be developed in any industry. (He sold the company to Siebel Systems in 2000 for $610 million.) In 1994, he started Interactive Data Systems, an electronic catalog technology provider. Hornung holds a BS degree in business marketing from the Crouse Hinds School of Management, Syracuse University.

“Fabricators will be able to acquire the technology one window line at a time so Sashlite can co-exist with other technologies nicely. This ease of installation and its adaptability make it a very powerful and practical technology,” he said.

The consumer will see a direct benefit from Sashlite, Hornung explained, in a number of ways. These include better structural performance and more thermally efficient windows that look better.

There are windows, however, where Sashlite is not recommended at this time.

“This system does not work on mechanical, fastened windows or aluminum products,” he said. “We have carved out applications that we know will be successful. As we develop a track record, we will look into other applications.”

But Hornung may not have to wait very long. “We’ve designed and engineered a way to apply the Sashlite technology to fixed windows (the upper panel of single-hung units, picture windows, the fixed side of sliding patio doors),” said Phil Morton, vice president business development of Dayton Technologies.

“We’ve solved that problem with patents that are in the process and this will give us a significant advantage to leverage the Sashlite technology. And, we are excited about that!”

Partnering That Makes A Difference

Moving from concept to reality involved partnering with manufacturers to produce product and develop the technology, explained Hornung.

“It was crucial that we select development partners with a reputation in the industry to help establish our own credibility when introducing this new technology.”

HB Fuller was selected to develop and manufacture sealant and desiccant matrices for the system. Kristen Gray, HB Fuller’s business development manager for the Sashlite project said three products were developed for the new technology: SashPlug™ hot-melt butyl, a 100- percent solids, single-component sealant designed to seal or plug the vacuum and/or the gas fill hole; SashSeal edge sealant, (a patent-pending technology), a onepart, warm-applied, moisture-curing system; and, SashDri, a desiccated barrier material.

“We have a beta (introductory) program with Sashlite offering support with application, installation equipment, training and visual aids,” added Gray, “which includes multi-lingual programs as well as instructional visuals to help orient operators to the new process.”

Other partners playing a key role in developing technologies include Dayton Technologies, producer of vinyl window and door systems; Vinyl Building Products, lineal vinyl manufacturer; Ashland Hardware, manufacturer of hardware and specially designed muntin clips for Sashlite; Mikron Industries, manufacturer of vinyl and wood composite window and door profiles; and FDR Design, supplier of gas-filling equipment.

Vertical Ventures and Erdman Automation teamed up to create Sash Systems, LLC which provides a full product offering of semi-automated, automated and handling equipment to support the Sashlite technology.

According to Ralph Weiss, president and CEO of Vinyl Building Products, the company is developing a full product line based on the Sashlite technology. Products will include single and double hung sliding windows and casement windows, as well as a sliding door. There will also be the addition of a swing door to be developed at a later date.

“We will offer the entire package to our customers,” said Weiss. “That's what the market wants so we are offering this to our fabricators.”

Trial Runs

Describing the first day of the trial run at Window Shapes, Tom Change, general manager said the equipment looked good and set-up was very simple.

“We were up and running in a matter of hours, which is almost unheard of for any new start-up,” he said. “The training of our operators was excellent. Our training session was focused and very informative. The instructor took us through a step-by-step process, emphasizing proper glass handling, followed by a demonstration. And, all of our concerns were addressed.”

For Paul Del Bianco, manufacture support specialist for Vinyl Building Products, this set-up was as expected “which is just the way we like it.”

“I was impressed with the team of people who got everything going. They were knowledgeable and very accommodating. We will be using less space to produce more product because this technology enables us to operate as a single-cell product (produce an entire product from start to finish). Six months ago, this concept was first mentioned and, based on the benefits and advantages, we gave it serious thought. What convinced us to go ahead with Sashlite was the validation of laboratory testing (from HB Fuller and simulations from the National Fenestration Rating Council). Test results were not only impressive but beyond what we were projecting. Needless to say, we are very excited about being pioneers in this latest technology and the prospect of benefiting from the cost savings,” said Change.

Window Shapes is the second company to incorporate the Sashlite technology into its operation.

Plans are underway for the next trial run.

Thermal Performance Testing (NFRC Simulation)
Sashlite Super Spacer
Edge of glass U-value 0.51 BTU/hr/ft2/F 0.54 BTU/hr/ft2/F
Frame U-value 0.58 BTU/hr/ft2/F 0.59 BTU/hr/ft2/F
Overall U-Factor 0.51 BTU/hr/ft2/F 0.51 BTU/hr/ft2/F
Charts courtesy of HB Fuller. Testing performed by the National Fenestration Rating Council.

“We’re very excited about the opportunity this technology presents to us, particularly to improve the thermal efficiency and quality of our units,” said Howard Rose, president of United Window & Door, described as one of the top 100 fabricators in the country. “What I like is that there are no site-line issues because the unit is part of the frame. We think this will change the entire window and door manufacturing business. In fact, I believe it has the potential to revolutionize this industry in the way we do business. We like to think of ourselves as innovators and Sashlite gives us the chance to be at the forefront of an innovation that no one else has.

Thermal Performance Testing (NFRC Simulation)
Edge of glass U-value (W/mK) 0.51 BTU/hr/ft2/F 0.59 BTU/hr/ft2/F
Temperatures (ºF):    
3 inches above frame 45.2 44.9
2 inches above frame 45.0 44.2
1 inch above frame 43.8 39.1
At the frame 39.3 40.0
Testing Info: Cold side 0°F, Hot side 70°F, 2 foot by 3 foot unit, 1/2-inch airspace.

Charts courtesy of HB Fuller. Testing performed by the National Fenestration Rating Council.


“We are also encouraged by the development partners like HB Fuller, which, from our experience, gives instant credibility as well as a comfort level for the commitment we are about to make. The results speak for themselves. It works and it gives you a better unit,” added Rose.

“We see this as an opportunity to be on the ground floor with a technology that could change the way we manufacture insulating glass,” said Nick Derrico, vice president of sales. “Initially, we will use Sashlite as a single cell for making our patio doors and then go from there. This could be a paradigm shift in business over the next four to five years as a significant step in the market.”

Thermal Performance Testing (NFRC Simulation)
Sashlite Swiggle Spacer
Edge of glass U-value 0.51 BTU/hr/ft2/F 0.59 BTU/hr/ft2/F
Frame U-value 0.58 BTU/hr/ft2/F 0.71 BTU/hr/ft2/F
Overall U-Factor 0.51 BTU/hr/ft2/F 0.53 BTU/hr/ft2/F
Charts courtesy of HB Fuller. Testing performed by the National Fenestration Rating Council.



The first use of the Sashlite technology took place in the fall of 2003 at Survivor Technologies Inc. in Hillside, N.J., a supplier of vinyl windows to Lowe’s. Survivor has licensed the technology and has gone from a successful beta  testing to production of its new casement design.

John Rovtar, director of technical service and product development, is very excited about the new technology. He says the overall process is easier. Less space is needed and there isn’t as much machinery to maintain. He also mentioned that he is seeing a 10-percent improvement on energy performance.

According to Anthony Balestro, vice president of operations, the process is simplified significantly. He said Sashlite gives them better structural performance and better energy performance which ultimately is a better product. Rovtar indicated that the next step will be to look at expanding Sashlite for the production of its double-hung and slider units.

Thermal Performance Testing (NFRC Simulation)
Sashlite Cardinal Aluminum
Edge of glass U-value 0.51 BTU/hr/ft2/F 0.64 BTU/hr/ft2/F
Frame U-value 0.58 BTU/hr/ft2/F 0.74 BTU/hr/ft2/F
Overall U-Factor 0.51 BTU/hr/ft2/F 0.55 BTU/hr/ft2/F
Charts courtesy of HB Fuller. Testing performed by the National Fenestration Rating Council.


Looking Ahead

Hornung and France have good reason to be enthusiastic about their venture. They are seeing the fruits of their labor after more than three years of product testing and development by HB Fuller.

“We have a stable technology because we took the time to develop products and overcome any obstacles that existed,” said Hornung.

According to Darwin Brown, president of Deceunick North America (parent company to Dayton Technologies and Vinyl Building Products), there are many benefits to using Sashlite including lower cost, better thermal performance and a better product.

Paul Warner, co-president of Mikron Industries says that the Sashlite technology has a lot of possibilities. Because their customers favor cell manufacturing, the technology has a lot of appeal.

Alan Levin, president of Northeast Building Products, describes Sashlite as a great concept.

“HB Fuller has done enough product development to show thermal efficiency and structural performance and the cost analysis shows savings. I believe this is the future of the industry. I would say that in ten years, the majority of windows will be made this way.”

“As one of the development partners, we’ve been involved from the very beginning. While we had some initial concerns about the PVC and how well it would withstand temperature extremes and ultraviolet exposure, we knew if HB Fuller could solve the technical hurdles, then the enhancement to window design would be tremendous. Sashlite is the perfect match between product and technology for high performance,” said Morton.

He added that there are a number of advantages.

“There is amazing rigidity of the sash panel and because the glass is sealed in two places, the unit should have a high durability factor and long life. The process has fewer elements, less assembly steps in less space with less people and fewer opportunities for error. The result is that we think the fabricator will produce a better unit. Site lines will be perfectly aligned which makes the product technically and cosmetically better. And, now that the spacer is an integral part of the PVC extrusion, the color of the spacer and profile can be matched. Overall, we are very excited about this technology. We realize it will take time for the fabricator to adapt to this new process. But where there is a product with benefits, it is bound to win approval,” said Morton.

The enthusiasm for Sashlite, however, is not universal. For some, it is too early to determine its value and the impact it may have. For others, there are issues.

“We view Sashlite as unique and unusual. From what we can see at this early stage, it has some potential limitations,” said Ric Jackson, director of marketing for TruSeal Technologies Inc. “In all fairness, the industry has a lot to learn about the system before judging its performance. Time will tell whether it will be successful and to what degree window producers will accept and adopt it.”

“We feel it is too early to judge the merits of the Sashlite technology, and we will continue to focus on the advantages of our warm-edge products,” said Dick Schellhase, sales manager at Allmetal.

“Several companies have tried to eliminate the IG manufacturing process of making a window, and Sashlite has come the closest to doing so; however, a few things need to be considered when looking at this system,” said Larry Johnson, executive vice president, Edgetech IG Inc. “Glass needs to be produced in a clean environment, the system does not have a full family of products and you have to pay a royalty. A big drawback is that replacement of broken glass is more expensive because you end up throwing away the glass, sash, sealants, desiccant—and the royalty. This could potentially become a costlier spacer system than manufacturers had anticipated.”

Hornung attributes the performance of the Sashlite technology to its unique approach and to the resolve and efforts of the development partners.

“We created an incubator with the industry’s most knowledgeable players and the test results are excellent across the board, ” he says. “Sashlite’s manufacturing process is extremely flexible from the time a company adopt’s the technology to fabrication in small but high volume cells.

“Our development partners are working with a fabricator base to design and implement the next generation of products for the industry, he adds. Hornung acknowledges that the Sashlite technology does require replacement of the entire sash which, he says, has become widely accepted by many companies in the field today.

“This could be considered a trade off as many customers have preferred an interest in sending out a replacement sash which has many advantages to care, packaging and ease of installation.

“The fabrication of Sashlite products, including royalty, proves the system is more efficient, better looking and cost effective,” Hornung said.

He added that the company has issued patents for Sashlite and has numerous domestic and global patents-pending for other technologies. With a mission statement, “to develop advanced technologies that create industry-changing events in the window industry,” he is right on target. Based on test results, successful trial runs and production of Sashlite, Hornung’s first technology for vinyl window making could revolutionize an entire industry.

Alan Goldberg is a contributing writer for DWM. He has more than 30 years of experience in the insulating glass industry.