OK, so maybe it’s time to redo the basement. Maybe we just need some

insulation on those bare, freezing cold, concrete walls. Canadian winters can take a toll

on the energy bill, and your comfort level. Maybe we want a full renovation to have

ourselves an amazing man cave, or a beautiful new suite. Or, maybe we just need some

extra room for the kids to play around in. Whatever your reason, redoing/finishing your

basement is one of the greatest ways to increase the value of your home, and to add some

usable square footage. However, if you plan on insulating with fiberglass insulation I

hope to persuade you otherwise.

Fiberglass insulation is effective in some building assemblies, and the intention of

this whitepaper is not to dismantle the reputation of fiberglass insulation all together.

However, the intention of this whitepaper is to exclaim that fiberglass insulation should

NEVER be used in basements.

There are two main points that are important in understanding why fiberglass

insulation is the worst thing to put in your basement. First, we will discuss the many

health risks and dangers associated to having fiberglass insulation in your basement.

Second, we will discuss the facts as to why fiberglass is NOT an effective insulator in

basement assemblies. However, it wouldn’t be fair to provide a bunch of problems

without providing alternative solutions. As we go I will introduce other insulation

products that are much more effective, and less hazardous. At the succession of this

whitepaper I will introduce one product that can alleviate all worries regarding basement

insulation, while also having other added benefits.

What’s growing in your walls?

Lets start off with an unsettling question. Would you eat a mouldy sandwich?

Probably not. Hypothetically, if you had to ingest some food that had been in your

cupboard for 2 years would you pick the 2-year-old sandwich, or the preserved can

beans? The beans of course! As silly as this analogy is, it is important to see we would

all make the obvious choice of a product that cannot become mouldy. Then why would

we choose an insulation product

that has a very high potential for

mould? Unlike a sandwich,

fiberglass insulation cannot get

mouldy by just sitting in a

cupboard. However, in an

environment with moisture and

an inability to dry (due to a poly

vapor barrier necessary when insulating with fiberglass) fiberglass insulation absorbs

moisture and eventually has the capacity to harbor mould and mildew. In a perfect

world, if we could eliminate any potential for moisture fiberglass insulation wouldn’t get

mouldy, but basements in Canada are not a part of that perfect world. Far from it.

Basements are inherently moisture prone. Whether there are cracks in the foundation,

improperly sealed/defective windows, improper downspout locations, grading issues,

plumbing problems, or just high interior humidity, there are almost always high levels of

moisture in basements. What if your home doesn’t have any of these issues? Well, when

the winter comes and the interior of your home is warm, and the concrete is cold, you

Mould found in basement walls insulated with fiberglass

will still get problems with condensation on the concrete when warm meets cold due to

convection and thermal bridging (which I will explain later).

A study by the Canadian Mortgage and Housing Corporation on mould in

basements showed that “[o]f the 27 houses tested, 16 had visible signs of moulds present

in the wall cavity…dangerous moulds were found in 15 of these houses while pathogenic

mould was identified in the 16th house.” Approximately 60% of the homes in the CMHC

study had mould, and of those basements 94% had dangerous mould. It’s important to

note that just because 40% of the homes in this study didn’t have mould, this doesn’t

mean they won’t have mould eventually. 60% is a huge percentage. If you and your

friend both have fiberglass insulation, odds are one of you has mould. The study

concludes saying the “presence of toxic and pathogenic moulds in basement wall cavities

is a common occurrence and requires ongoing attention by individuals in the fields of

health and building sciences”. Finally, to knock home (or Holmes) the problem of mould

is the well-recognized contractor Mike Holmes in a globe and mail article. Mike states:

And, no matter what, if you insulate your basement the same way you do an above grade

wall – using wood studs against the wall, with batt insulation in between and vapour

barrier over that – you will have air movement and problems with condensation, and very

likely, with mould.

Fiberglass insulation doesn’t belong in basements due to its inherent ability to

absorb moisture, and thus harbor mould and mildew. Unlike a mouldy sandwich, you

can’t just throw away a basement insulation system. A full demolition is required, and

the costs are incredibly high. Why would we let ourselves, or our children, live in an

unhealthy environment? Instead, we should insulate with materials that cannot absorb

moisture. By using water resistant products such as ROXUL (a fiber insulation made up

of Basalt rock and recycled slag), Spray Foam, and closed cell Expand Polystyrene (EPS)

we can nullify any moisture problems. Wood studs have the capacity to absorb moisture

as well. By using galvanized steel framing members, instead of wood stud framing, we

can avoid mouldy and rotting wood.

Fiberglass insulation may have many negative attributes, but according to the

North American Insulation Manufactures Association there is not enough “conclusive”

evidence to deem fiberglass carcinogenic in humans. This has been debated for years,

but lets be optimistic and say fiberglass doesn’t cause cancer. So, fiberglass may not

cause cancer, but can it prevent it? Mould isn’t the only hazardous substance that lurks in

our basements.

Radon gas has begun to get notoriety throughout the country. What is Radon gas?

Health Canada defines Radon as a “gas produced naturally by the breakdown of uranium

in soils and rocks that occurs naturally in the environment”. Oh, and it’s also the second

leading cause of lung cancer in Canada. Radon is released from the ground and seeps

into basements through cracks in foundation walls and floors, sump pits, gaps around

pipes, and basement drains.

According to Health Canada

“[r]adon moves easily through

concrete-block walls because they

are so porous”. Ok, so how does

this relate to fiberglass insulation?

Well, our traditional insulation

methods aren’t considered “radon

barriers”, and this is why fiberglass

insulation cannot help prevent cancer. Radon barriers like SlabShield can be installed

before the foundation is poured. Yet, if your doing a renovation the foundation is already

poured, and you’re basically out of luck. There are Radon professionals who can test

your basement to see how high the Radon levels are. Many Radon professionals can

perform a task called “active soil depressurization” which consists of installing a pipe

through the foundation floor to reduce Radon gas. Better yet, what if your insulation

system could also be considered a Radon barrier? At the succession of this whitepaper I

will introduce a product that can insulate your basement and protect you from Radon gas.

All points considered, fiberglass insulation is at the very least a good insulator in

basements, and should help us save some money on our energy bills, right? Not exactly.

In the next section I will explain why.

The R-value Fallacy

How Radon gas enters a basement

In laymen’s terms, R-value is the measurement of how well a product insulates.

To explain why traditional fiberglass insulation doesn’t perform well in basement wall

assemblies we need understand the difference between “Nominal” R-values and

“Effective” R-values.

To help explain the difference between Nominal and Effective R-values we will

look at our sandwich analogy again. In this analogy lets imagine we are judging

something on how well it tastes. There are many types and qualities of bread, and some

may taste better than others. However, if you were to make a sandwich with very tasty

bread, and nothing else, would that really be a tasty sandwich? No, it would be bland and

terrible. However, when you add other products into the sandwich (meat, mayo, lettuce,

cheese) well, then that sandwich is going to be delicious. Therefore, we must measure

how delicious a sandwich is based on the entire sandwich, not just on the bread alone.

That is the difference between Nominal R-value, and Effective R-value. Nominal R-

value (the bread in our analogy) is based on how well a specific material insulates with

no other products taken into consideration. Effective R-value (the sandwich in our

analogy) is based on how well an entire building assembly performs in its entirety.

Effective R-value is a true R-value. Fiberglass insulation has a Nominal R-value.

Now let’s take a look at what happens to Nominal R-20 fiberglass installed in a

wood frame assembly.

ASHRAE A3-1D table used to convert Nominal R-value to Effective R-value

Remember, R-20 fiberglass by itself, not in a wall assembly, without any wood,

or concrete, or real world application, performs at R-20. Once R-20 fiberglass is installed

in a 16 O.C. wood stud wall the R-value drops to 13.4. This R-value of 13.4 is

considered an Effective R-value because it takes into account the wood studs. The reason

why the R-value drops when the insulation is added into a wood frame assembly is due to

thermal bridging. A study done

on thermal bridging states that

“[t]hermal bridges provide a path

of lesser resistance through the

insulation, allowing more heat to

bypass the thermal barrier and

raise or lower interior

temperatures”. Basically, energy

travels through the wood studs

and out the wall, energy that could have been used to heat your basement. Metal studs

are even more conductive than wood. R-20 fiberglass falls dramatically down to an

Effective R-value of 5.2 when we insert a more conductive product like steel studs. That

is almost a 75% loss in R-value. The more conductive a material is the more potential for

energy loss, which is why we don’t insulate our homes with pots and pans, or cook our

eggs on insulation. Thermal bridging also causes problems with condensation on the

interior side of concrete walls. This is due to heat travelling through the framing member

and meeting the cold concrete wall. Now we have condensation, and potential for

moisture. How do we solve this thermal bridging problem? To avoid thermal bridging it

is necessary to have a continuous thermal barrier. Basically, you need something that

insulates between the framing members and the concrete wall. By installing foam

insulations like EPS between the framing members and the concrete wall we can nullify

the problem of thermal bridging. Yet, thermal bridging is not the only thing that can

drastically reduce the Effective R-value.

Infrared image showing thermal bridging through framing

members

We discussed earlier the high potential for moisture in basements, and the health

hazards that coincide with moisture problems. Well, moisture doesn’t just help mould

grow, moisture also destroys

Effective R-values. The IRC

have conducted studies

showing that when moisture

is found in insulation there is

“a reduction [in R-value] of

60% to 70%” and that

“reduction is so drastic that it

is debatable whether the

material can be considered a

thermal insulation.”

Therefore, moisture

is detrimental to the

effectiveness of insulation.

Oh, air infiltration also

reduces the Effective R-value quite dramatically. That poly vapour barrier better be

sealed perfectly.

A Solution

Since the 1950’s people have been using fiberglass insulation as a way to insulate

their basements. Today, 65 years later we still use the same methods to insulate. How

IRC graph that shows the effectiveness of Dry insulation vs Wet insulation

many products and systems from the 50’s, that haven’t been adapted to our modern

society, do we actually use today? Very few. So, why do we continue to insulate our

basements using traditional fiberglass building methods? Let’s recap what we discussed:

-Fiberglass insulation has a high potential for mould in environments that are

moisture prone.

-Basements commonly have moisture problems.

-Radon is the second leading cause of lung cancer.

-Fiberglass insulation cannot protect against Radon.

-Basements have a high potential for increased Radon levels.

-Nominal R-values are not useful in determining how well a product insulates in a

wall assembly.

-Fiberglass insulation uses Nominal R-values to describe its effectiveness in wall

assemblies.

-Fiberglass R-value drops by almost 40% due to thermal bridging.

-Fiberglass R-value drops by almost 70% due to moisture.

-Fiberglass R-value drops when there is air infiltration.

Maybe its time to move on from insulation methods we used 65 years ago. Maybe its

time we look at a more modern insulation system.

Quik-Therm Insulation Solutions has developed a product designed specifically

for the interior side of basement walls. This system is called Quik-Therm Concrete

Insulation System (CIS). Quik-Therm CIS is an entire system made up of closed cell

Expanded Polystyrene (EPS) with a reflective polymer face, galvanized steel angles, and

plastic stud stabilizers. The

components that make up

Quik-Therm CIS are all

completely impervious to

moisture. So, even in the

extreme event that your

basement floods (hopefully it

doesn’t) Quik-Therm CIS will

not absorb any moisture.

Since Quik-Therm CIS cannot absorb moisture, it is then unable to harbor mould and

mildew. What about Radon gas? Well, Quik-Therm CIS is also an effective Radon

barrier. Now we have ultimately eliminated the second leading cause of lung cancer

from being transmitted into our basement. OK, so Quik-Therm CIS can provide us

peace-of-mind knowing we are living in a safe, and healthy environment, but what about

its ability to insulate?

Quik-Therm CIS is an entire system and has been tested to Effective R-value’s.

The R-values range from Effective R-17 at 2 ¾” thick to Effective R-22 at 4” thick.

Therefore at 4” thick Quik-Therm CIS is

almost double the Effective R-value of

fiberglass insulation. The reason why Quik-

Therm CIS has such a high Effective R-value

is due to its design. It is a complete thermal

barrier, which means it doesn’t allow for

Quik-Therm Concrete Insulation System

Infrared image of Quik-Therm CIS. Note: No thermal

transfer. Temperature remains consistent

thermal bridging. Quik-Therm CIS is impervious to moisture, which nullifies any R-

value drop due to moisture. Quik-Therm CIS is also an air, vapour and radiant barrier.

Along with its high Effective R-value, Quik-Therm CIS has been designed with the

DIYer in mind. The product is incredibly simple, and easy to install.

After looking at all the possible problems fiberglass insulation has to offer we can

see that there are better products designed for basement wall assemblies. Lets walk away

from insulation that can be potentially dangerous and harm our health. Lets walk away

from insulation that doesn’t perform as well as it states. Lets walk away from 65-year-

old technologies. It’s time for a change. There are other alternatives out there. Don’t

insulate your basement with fiberglass insulation.

Click here for more information on Quik-Therm CIS.

References

Fugler, Don. Canada. Canada Mortgage and Housing Corporation. Molds in Finished

Basements. Ottawa, Ontario.: 1996. Print

Holmes, Mike. Canada. Globe and Mail. Mike Holmes. Toronto, Ontario.: 2007. Web

Canada. Health Canada. It’s Your Health. Radon.: Mar. 2002. Web. September 2012.

Totten, Paul., O’Brien, Sean., Pazera, Marcin. The Effects of Thermal Bridging at

Interface Conditions. Print.

Canada. National Research Council of Canada. 3BNRC Concrete Basement Findings.

Concrete basement findings presented to major cities in 1990. Print.