Reflective Insulation – Measuring Its R-value V/S Fiberglass

Reflective Insulation R-value Facts

FACT #1:
The R-values of reflective insulation and mass insulation are based on the same
fundamental equation: The ability to stop heat transfer.

FACT #2:
Reflective Insulation is a system that reduces the transfer of heat across air
space by the use of two surfaces having high thermal reflection and low
emittance (typically metalized film) + an inner substance + trapped airspaces.
U.S. Department of Energy: “Reflective insulation incorporates radiant
barriers — typically highly reflective foils — into insulation systems that
can include a variety of backings, such as Kraft paper, plastic film,
polyethylene bubbles, or cardboard, as well as thermal insulation
materials.”

FACT #3:
The R-value of reflective insulation is the measurement of the system rather
than a measurement of just the product. Measuring the R-value of the system (a
real-world application) is a truer measurement vs. a measurement of the product
only. Click for real-world test parameters (technical brochure). For example,
what good is the posted R-value of fiberglass given that once installed in an
environment that includes any moisture it loses R-value? Virtually all
real-world environments include some humidity. Unlike fiberglass the R-value of
Radiant Barrier USA is NOT affected by humidity.

Measuring
the R-value of Fiberglass Insulation

FICTION:
The posted R-value of fiberglass and cellulose insulation

The parameters of the R-value test for fiberglass and
cellulose insulation involve no moisture or wind. You might be saying,
“That’s ridiculous. That can’t be. Those aren’t the conditions of my home
or building.”

Even in the desert there is humidity. All buildings and
houses leak air and water. Water vapor from the atmosphere, showers, cooking
and even breathing move back and forth through the walls and ceiling. Those of
you in humid areas may lose half of your R-value with fiberglass or cellulose
insulation.

Fiberglass is assigned an R-value of 3 to 3.5 per inch.
Remember it will only achieve this number in a zero moisture and zero wind
environment. Fiber insulation placed in an improperly sealed house will allow
wind to blow through it as if there were no insulation at all. In the event of
flooding the R-value goes to zero. Even small amounts of moisture will cause a
dramatic drop in fiberglass and cellulose insulation’s R-value. The question
you should ask Mr. or Ms. Fiberglass and Cellulose is, “What is your
R-value in my real-world environment?

U.S. Department of Energy: “The R-value of some
insulation also depends on…moisture accumulation.”

The R-value of fiberglass insulation is derived from the
air-pockets between the fibers! If you compress the insulation, or allow it to
get moist, you lose the air-pocket and lose R-value! For those of you the like
to get into the weeds, I’ll explain in more depth why fiberglass loses R-value
once wet.

Fiberglass insulation is composed of woven fiber stands. The
fiber strands contain hundreds of small air pockets. The air pockets provide
the insulation. Once exposed to moisture, the air pockets fill up with water
(rather than air) and the insulation loses the ability to provide R-value.

Beware of fiberglass and other mass insulation products
pitchmen criticizing reflective insulation. On blog sites, they often present
themselves as “energy experts”. They’re all over the internet –
Backed by the marketing strength of the GIANT 30 billion-dollar fiberglass
industry. Ask them, “Why do you criticize reflective insulation’s R-value
being measured as a system (incorporating an airspace), while fiberglass
derives its R-value from the air pocket in the fibers? Why don’t you show the
parameters of your testing? Why don’t you include an * next to your R-value
claims that lets people know the values were achieved in an environment with no
moisture?

Radiant Barrier USA demonstrates transparency
by displaying how it measures the R-value of its products – Every R-value on
website is displayed as a link. Every R-value link goes to the parameters of
the testing. You had to learn from us that that the fiberglass R is derived
from air pockets in the fibers. You had to learn from us that the R-value
measurements of fiberglass was achieved in an environment with no moisture (not
real world).”

Ultimately, its’ not our opinion or that of the competition
that counts. It’s the opinion of real people that have actually purchased and
used the product that counts:

Buy Radiant Barrier USA Reflective Insulation with
Confidence