Case Studies

SIGA Cover

Celebrating 50 years as the choice airtight building envelope solution driven by the science of adhesives

Brothers Marco and Reto Sieber were always doing science experiments in their family’s kitchen and testing out their creations. They got their curiosity from their father, Paul Sieber, who laid the foundation for SIGA Cover, a global family-owned company with 400 employees and dozens of efficient building-envelope products for residential and commercial indoor air sealing and external moisture management.

SIGA began in Switzerland in 1966, established by Paul and his wife, Trudy Sieber-Gadient. The couple used their last names as inspiration for the company’s name (SI)eber + (GA)dient. SIGA’s first production plant was in the kitchen and later expanded into the family’s chicken coop.

SIGA Cover

Shifting to building envelope sealing solutions

Shortly after World War II, Paul began to repurpose medical plasters from the U.S. Army, cutting them into strips and selling the paper to factories as head tapes for writing pads and other office supplies. Until the late 1970s, SIGA developed adhesive tapes for a large variety of industry applications, including carpet tape.

“In fact, a similar kind of tape is still used to lay down the carpet at large trade shows like Greenbuild,” says Patrick McMahon, regional manager of SIGA, Western, U.S.

For some time this was SIGA’s main product line, but when the energy crisis started to hit home in central Europe in the late 1970s, the company began to shift its focus. Reto joined SIGA in 1980 and Marco in 1982 and they started to work more exclusively on building envelope products.

“At this time Europe implemented tight restrictions on new buildings and more energy codes,” says McMahon. “The code was a step ahead of the available technology and some builders began to use SIGA carpet tape for wall and air sealing. Marco and Reto realized they had an opportunity to develop building-specific solutions.”

Breathe easy with toxin-free, long-lasting products

SIGA sold off the carpet adhesive line and began to grow the number of building envelope products it produced, focusing on indoor air sealing and outdoor moisture management. “Today we manufacture all of our own products in Switzerland,” says McMahon. “We use all toxin-free, solvent-free, VOC-free products. We want to make an airtight building envelope and increase the indoor air quality.”

Not only do SIGA’s products make for an airtight, energy-efficient seal and lower CO2 emissions, they also have a longer service life. “Products with VOCs deteriorate over time,” explains McMahon. “When you’re talking about air sealing or moisture management you really want a product to stick for the life of the building; you don’t want to have to replace your window just because the flashing isn’t sticking anymore, you want to replace your window because it’s time for a new window.”

Promoting building science education

Since SIGA entered the North American market in 2011, the company has focused on delivering products and the educational tools to help builders make more informed decisions. “When we established a North American division we worked with the Passive House movement and offered education in building science,” says McMahon. “We want our customers and the industry to know the principles of building science and why it is important to do a good job in air sealing with a product that adds breathability.”

McMahon compares SIGA’s air sealing tools to a GORE-TEX ski jacket: “You wear it to stay dry on the outside, but also so you stay dry on the inside as it wicks away sweat,” he describes. “Other products are like a rubber rain jacket; they keep you dry but you end up sweating with unwanted moisture on the inside. In buildings, this condensation leads to mold and poor indoor air quality.”

At home in Switzerland, SIGA furthers its educational mission by running the SIGA Academy, a facility complete with its own 75-room hotel. “We train building professionals from around the world how to build and remodel with the SIGA method and products,” says McMahon.

This leads to a constant flow of new product innovations. SIGA has produced 34 international patents within the last 10 years. “We’re constantly coming out with new, highly-innovative products,” says McMahon.

This year at Greenbuild, SIGA will be showcasing its new Fentrim product. Fentrim has unique properties that allow it to adhere to masonry without a primer. “This product easily sticks to concrete without a primer — something that is unheard of,” says McMahon.

In Washington State’s rainy climate, SIGA is putting its products to the ultimate test at one of the state’s largest new high schools. “The new building trend is exterior continuous insulation, something we have been focusing on,” says McMahon. “We’re using our products to seal all of the building seams, acting as an air barrier, moisture barrier and insulation layer all in one.” The 350,000-square-foot project will be completed in 2017.

In-house manufacturing and innovation

By keeping manufacturing in-house, SIGA controls the quality and performance of its products. “We’re doing much more than taking a standard commodity product and calling it a tape,” says McMahon.

Behind all of this, SIGA has a strong company culture that stems from family ownership and the desire to innovate. On every 10th workday the entire company comes to a halt to check in across departments on new projects and any issues. Everyone from the apprentice to the CEO takes the time to check in, make changes and improve.

The company continues to find new solutions to persistent air and envelope sealing problems. Its products not only improve efficiency and indoor air quality, they also withstand the test of time and are why more and more customers have been sticking with SIGA Cover for 50 years.

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Spring 2018



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