BY ROBERT NAINI
SPRAY FOAM M Y T H S
(cont’d on the next page)
Spray foam insulation is a very interesting industry.
It has expanded from a small niche market that was custom
home-builder-centric, and has seemingly exploded to over a
billion-dollar industry in a relatively short 15 years or so.
Now, don’t get me wrong, spray foam has been around for
more than 15 years, but in the past 15 years it has moved from
being focused on the custom residential industry to include a
variety of applications:
• Residential Retrofits,
• Production Builders,
• Light Commercial,
• Large Commercial,
• Industrial, and more.
With this meteoric rise and the success of spray foam
insulation, there seems to be a never-ending list of market
assumptions, developments in the building code, and design
questions. Some of the questions are relevant and important,
while others are obviously founded in ignorance.
Let’s take a look at five myths that loom over the spray foam
industry and offer some clarification.
Imagine you are working your own booth at the local
You are in a 10' x 10' booth space. You’ve got a display that
compares open-cell, closed-cell, and fiberglass. It’s got light
bulbs that create heat in the bottom compartment and a fan
that pressurizes this compartment to show booth visitors
that air passes through the fiberglass, but not through the
open-cell and closed-cell foam. You’ve got pictures on display,
a flipbook of projects that you have completed, and a TV
showing a loop video with lots of rising foam to catch the
attention of attendees.
Can you picture it? You’ve been there before right?
The first person of the day walks by, the video of the rising
foam catches their attention and they say, “WOW, that’s cool.
What is this stuff? I’ve never seen it; it must be new.”
SPRAY FOAM IS NEW
While manufacturers are constantly developing new
formulations, to offer the market more competitive, higher quality
products, spray foam insulation is not new.
Actually, modern SPF dates back to the 1930s, when a German scientist, Dr.
Otto Bayer, discovered and received a patent for the fundamental chemical
reaction that is the foundation for polyurethane. In the 1960s, polyurethane
foam was commercially available and could be found in appliances,
furniture ,and automobiles.
All we have done is taken what was traditionally an in-plant application and
moved all of the equipment into a spray foam rig so we can roll out to a
jobsite and create an insulated “cooler” out of your building.
Soon thereafter, another attendee, looking at the side-by-side comparison
box, asks, “Closed-cell foam is better than open-cell foam, right?”
CLOSED-CELL FOAM IS BETTER THAN OPEN-
CELL FOAM OR OPEN-CELL FOAM IS BETTER
THAN CLOSED-CELL FOAM
It’s not as simple as one being better than the other. Closed-cell foam
is the better choice in some applications and open-cell foam is the
better choice in other applications.
Remember, open-cell foam has limitations:
• It’s not intended for exterior applications.
• It’s not intended to be used in below-grade applications.
• It’s not designed for contact with bulk water.
• And, it’s not a Type II vapor retarder.
Closed-cell foam is more versatile than open-cell foam, so if any of these
are design parameters, then yes, closed-cell foam is not only a better
choice, it is the only choice. This means that exterior building envelopes,
below-grade basements, wine rooms, pool houses, and other applications
with significant temperature and relative humidity differences, are all
obvious closed-cell foam applications.