It’s an Insulating Foam. No, it’s
an Air Seal. It’s Both an Insulating Foam
and an Air Seal
Remember the iconic
Saturday Night Live sketch about Shimmer, the dessert topping and floor
wax? http://www.nbc.com/saturday-night-live/video/shimmer-floor-wax/n8625?snl=1
Believe it or not, Chevy Chase wasn’t that far off.
Back in the 1950’s,
a man named Aaron Lapin invented an aerosol valve that he attached to a can of
whipped cream and invented Reddi Whip.
He later started packaging other products including polyurethane foam
through his company Touch and Foam. That
company is now owned by DAP Products, America’s largest manufacturer of caulks
and sealants.
Spray foams are used
as an easy to install insulation that offers an R-value of about 4-5 per
inch. But in addition to air sealing,
closed cell foams also prevent water leaks.
High-Performance
modular homes require great attention to insulating and air sealing. Mating walls, attics and sill plates are
three places where air sealing and insulating must be perfect. Spray foams are the best solution for these
applications.
The industry refers
to spray foam as either one-component (1K) or two-component (2K). You may not
think so, but there’s a big difference between 1K and 2K technologies.
One component (1K)
foams are easy to use but aren’t well suited for large applications because as
they cure, the small gas bubbles concentrate into large bubbles. The result is large gaps in the core of the
foam, which can reduce the sealing qualities.
This does not occur in smaller beads, but if you’re filling a large gap,
it may affect the quality and the insulation R-value.
1K foams can be
packaged three ways. The most common is
the readily available straw grade can.
It uses a plastic straw that attaches to the valve. Straw grade foams are somewhat messy to use
because of the run-on of the pressurized foam between the valve and the end of
the straw. They are also one-and-done, meaning that the
polyurethane foam can cure in the valve and is impossible to use again.
The
next step up is to use Gun Grade 1K foam like DAP Touch N’Foam Professional
All-Purpose Polyurethane Foam Sealant.
This uses a separate foam gun.
The gun’s valve is at the end of
the nozzle. There is absolutely no run-on, zero waste and a much cleaner
application.
Here’s the
challenge. Because many foam guns are
poorly made you may have been disappointed because they also seem to be one-and-done.
That’s not always
the case. There are hundreds of
different guns on the market and they don’t all perform the same. DAP has great confidence in the guns we
sell. They can be left on a shelf for up
to 30 days and will still perform.
Here are a couple
maintenance items to remember.
ALWAYS LEAVE A CAN ATTACHED TO THE GUN
Ok, just one
maintenance item.
Leaving the foam can
attached to the gun assures that there is no opportunity for foam to cure
inside the gun.
DAP and all other
foam manufacturers sell foam cleaners.
Cleaners are pressurized solvents that are used to clean out the guts of
the gun. To use a cleaner, remove the
foam can, thread on a can of cleaner and spray it into a trash can. Soon, it will come out as clear spray. Let it sit for a couple minutes then
repeat.
You only need to do
this once in a while to keep the insides of the gun clean. You can also use the spray tip to clean
uncured foam sealant off the gun barrel and basket.
Another thing you’ll
find is that you get more value with gun grade foam. Turbulence in the straw
may prevent the foam from fully forming and results in more density, limiting
how much yield you get out of a can.
For example, one
straw grade foam sealant yields about 250 linear feet with a ½ inch bead. That same product, in a gun grade can will
yield almost 700 linear feet.
So, by switching to
gun grade, even of a more expensive brand you will save time and money by
getting more sealant out of each can and wasting less time changing cans
out. You’ll have less trash and waste
too. Your crew will also work faster and
with more precision.
IK foams are also
available in large disposable cylinders similar to a propane bottle. DAP Touch ‘N Seal Quick Cure comes in 10 lb
and 16 lb cylinders complete with a hose and a wand. A 24 oz can of Quick Cure yields 1900 linear
feet of a ¼ inch bead while a 16 lb cylinder will yield 24,000 linear feet.
That’s 4 ½ miles of foam.
2K (two-component)
foams are quite different. There is no
risk of air pockets because the chemical reaction is part A mixing with part B. This gives
a highly defined cell structure and no air pockets which makes for
higher performance.
These
foams are packaged in a self-contained unit complete with hose and wand. To use a 2K foam, simply open the valves on
the A and B cylinders, attach the mixing nozzle to the wand and spray. This video shows how easy they are to use. https://www.youtube.com/watch?time_continue=5&v=Fds3pi8Ib0o
The DAP foam system
kits only require basic PPE. Safety
glasses, latex or Nitrile gloves and a respirator when working indoors. A disposable painters suit will protect your
clothing.
Surface and air
temperatures are critical with 2K foams.
Cylinders should be stored above 70°F and the surface temperature must be above 60°F.
2K foams are
measured in board feet of coverage. For
instance, a DAP Touch N’ Seal Foam System 200 will cover a 12” wide board, 1”
deep for 200 linear feet.
In high-performance
Modular construction, 2K kits are perfect for sealing mating walls and sill
plates, both areas where air infiltration must be controlled to achieve
excellent blower door and HERS ratings
along with homeowner comfort.
Another area where
2K foams excel is in attic insulation. A
1-2” layer of DAP foam between each truss joist performs three functions. It provides an unequalled air seal, a dense
first layer of insulation and helps provide for an acoustic damper to keep the
home interior quieter. Cellulose or
fiberglass insulation above that completes the insulation package.
This can also be
done during manufacturing on walls in conjunction with blown in or batt
insulation.
DAP 2K foams kits
range from 15 to 600 Board Foot sizes with even larger sizes available in
refillable units. They meet all applicable codes and standards
including flame and smoke ratings.
As an insulator and
an air seal, 1K and 2K foams are unparalleled in their performance with modular
builders. DAP stands ready to assist you
in your next project.
For more
information, go to www.touchnseal.com
or email [email protected]
