Hurricane Resistant – Product Development

How do you get building envelope products to meet the market need for hurricane resistance?

Good question!  Where do you start: windows, curtain walls or entrances & framing?  At first many thought, if it doesn’t open, close or lock it might be possible – or at least it should be easier.

Initial trial and errors:
After some initial R & D testing of standard off-the-shelf products it was clear they would not be able to meet these new impact and cycle requirements. Two common themes became apparent from the R & D testing: (1) these new products must be glazed with some type of laminated glass, and (2) the glass needs to be silicone glazed to the framing system.

Based on this premise, the glazing industry was off and running. The plan was to execute three basic steps: (1) design/modify existing products, (2) test the design, and (3) sell the product. After all, that’s what we do. Unfortunately, early product modification and testing efforts did not go as planned and the problems were numerous: glass failed, silicone failed, and hardware failed.

Small successes set the stage:
We didn’t give up, we continued to plow forward – weeks became months, months became years, and the years continued. Through mostly the dreaded trial and error process we began to make progress, modifying existing systems.  The persistence was starting to show results, and even though early product offerings, glazing infill’s and hardware options were limited – they passed the test.  The early R & D theories held true, incorporating laminated glass and structural silicone to hold the glass to the system.

A list of common impact resistant glass types can be viewed on the Kawneer web site. Go ->

A shift in approach allows for more product successes:
The shift in approach was key – now products are initially designed and developed with the impact/cycling requirements in mind. A product's ability to handle increased glass thickness is paramount. One of today’s practices is to incorporate the thicker monolithic laminated or insulating laminated glass requirements into a product’s basic design.

With the glass interlayer technology and system design improvements that have been made since the mid to late 1990’s, many of today’s systems can be conventionally glazed using dry gaskets in lieu of the structural silicone approach and still meet the stringent impact and cycling requirements.

Glass and glass interlayer manufacturers like DuPont®, Viracon, SAF-Glass and Saflex® continue to make product improvements.

Today’s offering no longer limited to only a few choices:
Today, product offerings include swing entrance doors, storefront framing systems, curtain wall systems, fixed windows, projected windows, hung windows, and sliding doors. Many of our products offer both the original glazing concept of laminated glass with wet glazing (structural silicone) and the newer glazing concept of laminated glass with dry gaskets.

A complete list of Kawneer impact/cycled tested products can be viewed on our website. Click on the link to see our Notice of Acceptance Documents (NOA) and Florida Product Approval Documents (FL).  Go ->

Be sure to let me know about your glass and glazing successes with impact resistant products…