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Please share IndoorAir.com with people you care aboutPage 2
Table of Contents
Why trust the author? .................................................... 3
Preface ........................................................................... 4
Sharing this book ........................................................... 9
The book series ............................................................ 10
Garage inspection ........................................................ 13
Wallboard walls ..................................................................... 14
Oriented strand board walls ................................................. 18
Masonry walls ....................................................................... 20
Garage vents that cause mold .............................................. 20
Overhead door mold ............................................................. 22
Trash cans ............................................................................. 22
Attic inspection ............................................................ 23
Attic access ............................................................................ 24
Roof leakage .......................................................................... 29
Attic venting .......................................................................... 30
Appliance venting .................................................................. 33
Air leakage ............................................................................. 34
Vermin ................................................................................... 39
Helping others .............................................................. 42
© Copyright 2017 Indoor Air LLC, All Rights Reserved
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Throughout my career, I’ve helped doctors discover causes for their
patients’ unexplained symptoms, and helped lawyers prevail in court cases
by testifying for clients who suffered physically and financially as a result of
real‐estate transactions, contractors, and insurance companies.
As an indoor environmental inspector, I have diagnosed thousands of
residential homes, condominiums, and apartment buildings, as well as
historic landmarks and commercial buildings such as churches, restaurants,
schools, universities, medical facilities, police and fire departments, and
shopping malls.
I’ve been interviewed by newspaper reporters and featured on television
multiple times. I’ve also assisted in writing home inspection laws and mold
legislation, as well as provided seminar training for housing authorities,
health professionals, building inspectors, real‐estate agents, insurance
adjusters, landlords, attorneys, builders, mold remediators, and a variety of
professional service contractors whose businesses are related to indoor
environments.
Why trust the author?
My name is Dan Schilling, and I have
spent over 30 years performing
unbiased building investigations and
teaching clients about conditions that
cause and contribute to health issues,
waste money, and depreciate
property value.
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Through my investigative work, I discovered many of the causes of the
skyrocketing numbers of people suffering from symptoms such as
tiredness, fatigue, headaches, behavioral problems, lack of concentration,
learning disabilities, memory loss, snoring, ear and sinus infections, eye and
throat irritation, chemical sensitivities, chronic sneezing and coughs,
allergies, and asthma.
With so many experiencing the negative and even dangerous effects of
poor indoor air quality in their homes, schools, and workplaces, I felt called
to share my discoveries and helpful information through economical,
accessible books, which cost far less than an onsite inspection and are
aimed at non‐professionals.
The books, with related inspection photographs included, are helping
people discover and understand the consequences of unhealthy indoor
environments as well as fix the problems in their own indoor spaces. The
information in the books also helps protect people from unscrupulous
contractors, real‐estate professionals, insurance companies, and those
purporting to be air quality experts.
I hope that you too will benefit from the information in my books as you
take steps to make your indoor environment safer and healthier to live in.
Preface
As a building inspector, I never intended to work in—or write about—the
field of indoor environmental health. My work requires compassion for
people, the drive of a scientist in search of truth, and knowledge not
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necessarily taught in a classroom. Thirty years after I started my career, I’ve
published this book about my discoveries and insights to help people live
healthier lives.
After a decade of investigating residential and commercial buildings, I felt
compelled to begin to explore indoor environmental health issues, because
I believed that so many of the defects I was discovering in buildings were
contributing to illnesses experienced by my clients and their families. Many
were either suffering related to indoor air or using over‐the‐counter and
prescription drugs to cope. Some of these building defects were due to lack
of maintenance; others were caused by contractors who either cut corners
or didn’t realize the consequences of their own work.
My own journey began when my furnace broke down in the middle of the
night during the winter of 1998. I knew what was wrong with it, so I called
a heating contractor friend who met me at his shop to give me the repair
part I urgently needed. While there, I noticed some strange‐looking objects
sitting on a shelf; they were about the size of a toaster and looked like
stereo speakers. When I asked him what they were, he told me they were
air purifiers that he was selling through his business. He then asked me to
take one home, try it, and let him know my thoughts.
Within 15 minutes of turning the unit on in my home, I noticed an
improvement in the indoor air quality. I called him the next day and told
him he was not getting the air purifier back! And I knew I wanted to learn
more about how they worked and offer them to my inspection clients.
After receiving my first shipment, I created a brochure that listed the
known symptoms related to indoor air quality. When I gave them to my
clients and asked if they or someone in their family suffered from any of
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the listed symptoms, in virtually every instance the answer was yes. Often
they suffered from multiple symptoms, and in some instances clients told
me their family members experienced all of the symptoms on the list.
My inspection clients started purchasing the air purifiers, and the feedback
I received was astounding. People were telling me that their allergies had
gone away, that they had stopped taking asthma medications, that their
headaches were gone, that they could sleep again, that their snoring had
stopped, that their houses no longer smelled like smoke, pets, or mold. The
list went on and on.
As an inspector, hearing these testimonies made me more curious. Humans
have been breathing air since creation. Why would we suddenly—over the
last few decades—have so many health issues and breathing disorders?
Why did allergy and asthma doctors have long waiting lists? Why were drug
companies manufacturing billions of dollars’ worth of over‐the‐counter and
prescription drugs to help alleviate symptoms for something as routine as
breathing?
As amazing as the air purification systems appeared to be, I felt I had to
know what was making indoor air so unhealthy in the first place.
I began to do some research and uncovered some basic reasons, but
quickly realized that indoor air quality issues are complex. So I set out to
discover other contributing factors with the understanding that indoor air
is like vegetable soup—all the ingredients collectively contribute to the
final product. In order to determine the correct solutions for my clients, I
needed to find out more about the root causes.
What was most interesting to me was that virtually all of the contributing
factors I discovered in homes and commercial buildings were combinations
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of construction errors and mechanical system defects that occupants did
not know existed, and things occupants were doing that were unknowingly
adding pollutants to their indoor air.
I also noticed a correlation between the increasing number of people
suffering from such ailments as allergies, asthma, and headaches, as well as
learning disabilities and memory loss, and the energy‐saving improvements
people began making to their homes and buildings in the 1970s. And I
believe that the overall number of people suffering from these symptoms
has grown exponentially worse as we’ve made our homes and buildings
more energy efficient.
Everything began to make sense when I connected the dots between my
building inspection knowledge, the indoor air quality problems, and the
health issues people were experiencing. The more I discovered during my
investigative work, the more I realized I had to provide people with the
help they needed to resolve their air quality–related health problems.
As my business focus changed from general building inspections to indoor
environmental inspections, people started spreading the word, and my
client base also changed. I began to work almost exclusively with people
who were already sick or who had justified reasons to believe that they had
indoor environmental conditions that could affect their health or the value
of their homes or businesses.
Since then, private and municipal building inspectors, attorneys, building
contractors, government health departments, holistic practitioners, and
medical doctors have all referred people to my investigation services.
I expanded my indoor environmental work across the United States,
discovering and teaching people the causes of their air quality–related
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health problems, showing them how to safely eliminate those problems
and prevent recurrence, and explaining air‐purification strategies to help
control contributing factors that none of us can eliminate from our indoor
environments.
After working with people nationwide, I realized how extensive indoor
environmental problems had become, whether the outdoor climate was
Arizona’s or Alaska’s. With every reason to believe that the problems
existed inside homes and buildings throughout the world, I knew this
information had to be shared with others, and hopefully taught in schools
and universities.
I began conducting seminars and discovered that many of the attendees,
including building inspectors, contractors, doctors, lawyers, and insurance
adjusters, wanted more instructional training to help them either do this
type of work themselves or become more knowledgeable in their own field
of work. As I tried to organize the information for these training seminars, I
became overwhelmed and wanted to make it available in an easily
accessible manner to all people, not just professionals.
To help as many people as possible, I decided to create a series of
affordable, user‐friendly ebooks containing practical how‐to information
with real‐life examples, illustrations, and photographs.
And so began years of writing and archiving photos while also trying to
meet my professional obligations to clients who urgently needed help.
Writing these books was more work than I ever imagined, but it was
justified by knowing that they are helping protect people from illness and
disease, as well as save them money in energy costs, protect them from
being conned, and help them maintain their property values.
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Sharing this book
If you’re reading this book, you’ve likely already read the book Six Steps to
Healthy Indoor Air. If not, please download a free copy at IndoorAir.com.
The book is packed with valuable information and available as a free gift to
help you begin understanding indoor air quality issues and solutions.
IndoorAir.com offers a collection of educational books derived from
decades of home and building investigations. The books are a resource for
people who care about the safety and health of their families and pets as
well as saving energy and protecting the value of their homes. They also
help protect you from being scammed by contractors, home sellers,
landlords, insurance companies, mold remediation companies, and those
purporting to be air quality experts.
All the books contain copyrighted and trademarked material. Please do not
distribute them illegally, but please do share the IndoorAir.com link via
email or social media to help others get started with their free and sharable
copy of Six Steps to Healthy Indoor Air.
Sharing the link helps those who suffer from allergies, asthma, headaches,
sleeping problems, learning disabilities, or other health issues, and helps
me save on advertising costs, which will keep all the books affordable for
everyone.
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The book series
There are over 100 different locations around homes where mold
commonly grows. Most often occupants have no idea how much mold is
actively growing in their homes because they do not know where to find it
or how to see it.
The Do‐It‐Yourself Mold Inspection book series explains how and why mold
grows indoors, and shows you all of the hidden places you should inspect
for mold growth in your home.
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The book series includes the following titles:
Part One Know Your Enemy
Part Two Hidden Moisture Sources
Part Three Attics & Garages
Part Four Kitchens & Bathrooms
Part Five Walls, Windows, & Doors
Part Six Carpet, Wood, Vinyl, & Tile
Part Seven Plumbing & Electrical
Part Eight Heating & Cooling
Part Nine Basements & Crawl Spaces
Part Ten Furniture & Personal Items
The table of contents for each book is viewable at IndoorAir.com.
This book is Part Three: Attics & Garages, and, like all the other remaining
books in the series, should only be read after you have read Part One:
Know Your Enemy and Part Two: Hidden Moisture Sources. Those two
books are critical to understanding parts three through ten.
Know Your Enemy explains how to make mold visible and familiarizes you
with all the nuances of mold growth to help you better understand mold
inspection. Hidden Moisture Sources explains all of the sources of moisture
that originate outdoors and indoors that initiate mold contamination
problems in indoor environments. After reading these two books, the
remainder of the series will be more understandable.
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When inspecting your home for mold, you are certain to discover multiple
areas of it that you were entirely unaware of. To learn the correct methods
of contending with indoor mold problems, I recommend reading the book
Do‐It‐Yourself Mold Cleaning & Prevention from IndoorAir.com.
This book will teach you mistakes to avoid so you don’t make matters
worse by spreading mold, as well as precautions to be aware of in the
event you need to hire a mold cleaning company.
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Garage inspection
An exterior inspection of a home includes walking through the garage. Like
the inside of a house, there are a number of places where mold can be
found growing in garages, and for various reasons.
Many garages have gypsum wallboard on the walls and ceilings, also known
as Sheetrock or drywall. The paper surface on wallboard comes preloaded
with mold spores right from the store because it is hygroscopic, which
means it can absorb moisture vapor directly out of the air. All that is
required for mold spores to germinate within the wallboard is for it to be
placed in a damp or wet environment, such as a garage.
Many garage walls are also covered with sheets of oriented strand board
(OSB). OSB is also used as sheathing behind exterior siding, and thus is
often exposed and visible from the inside of the garage. OSB sheets are less
expensive than plywood and have therefore been commonly used during
construction over the last few decades.
Similar to gypsum wallboard, OSB also comes preloaded with mold spores.
OSB products consist of man‐made lumber manufactured with chips and
strands of wood that were formerly considered waste during the milling
process. As a recycling effort, the wood scraps are now mixed with
adhesive resin and pressed together into sheets. Unfortunately, however,
these scraps of wood and bark are very hygroscopic and susceptible to
decay, and like wallboard they can absorb moisture vapor directly out of
the air. The mold spores within OSB products will germinate when exposed
to humidity or water.
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When mold is growing on these wall‐covering materials in garages, people
can be exposed to it repeatedly as they pass through the space. In addition,
the spores from mold growth on the materials can enter homes each time
the door between a garage and a house is opened. This occurs because
warm air will rush in and out of houses at the top of the door while cold air
rushes in and out at the bottom of the door at the very moment the door is
opened.
Below I will show you examples of mold growth on both wallboard and OSB
in garages.
Wallboard walls
Mold growth on wallboard is most common when the wallboard has no
paint coating, because paint tends to seal the wallboard and help reduce its
absorption of moisture from the air. In most garages wallboard is not
painted—but note that a coat of paint is not a guarantee against mold
germination.
Ambient humidity in outdoor air is enough to cause mold to germinate on
wallboard, and the humidity in a garage can be even higher due to
automobile activity. In Part Two: Hidden Moisture Sources I showed you a
photo of moisture vapor coming out of the tailpipes of automobiles. When
an automobile is started it produces a burst of moisture that lingers in a
garage even after people leave their homes and close their garage doors.
In cold climate areas, moisture from the air inside a house can also add to
the humidity in the garage. When a door between the two is opened, warm
moisture‐laden air exits the house through the top of the door to replace
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the cold air that rushes in at the bottom of the door. The warm moisture
rises up to the ceiling and can cause mold to germinate and subtly grow
directly above the door.
Mold that germinates on wallboard due to humidity is most commonly
white or amber in color, making it very difficult to see, so look carefully.
The white ceiling in the photo on the left is covered with a fine layer of
white mold that the homeowner did not know was there. Similarly, the
amber‐colored ceiling on the right is covered with amber‐colored mold that
is barely visible in the photo.
Distinctly visible mold can also grow in garages, however, due to water
incursions from roof, plumbing, and siding leaks.
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The photos above show examples of visible mold growth due to a plumbing
leak and a roof leak.
This photo shows mold growth on the garage ceiling due to a second story
siding leak at the bottom flashing. The wall with the water stains abuts the
occupied area of the house, which means it is an insulated wall and likely
has a significant amount of hidden mold growth inside it.
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Garage windows are often lower quality than house windows and
frequently have no storm windows or caulk sealant on them. This condition
can allow water to enter a wall and then cause mold to grow on the wall
and/or inside the wall cavity. If the wall cavity is insulated, the likelihood of
mold growth inside it is increased.
Wallboard is never supposed to be in direct contact with concrete, as it can
absorb moisture directly out of damp concrete as well as liquid water that
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runs off of wet or snow covered automobiles, both of which cause the mold
spores in the paper facing to germinate and spread.
Oriented strand board walls
The photo above shows garage walls that are covered with OSB. Like
wallboard, OSB is also not supposed to have direct contact with damp
concrete because it can absorb moisture from the concrete and then grow
mold.
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Due to the variety of colors of the wood scraps used in OSB products, mold
growth on its surfaces can be very difficult to see, yet the mold can cover
vast amounts of surface area and can introduce amplified levels of mold
spores into the air that can result in illness. The photo above shows a close‐
up of a very small area of OSB with mold growth on it. I enhanced this
photo to make the mold more visible for you.
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Masonry walls
Concrete walls in garages are cold surfaces and therefore attract moisture,
as well as dust particles. Together they provide the food and water
necessary for mold germination and growth.
Garage vents that cause mold
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The photos above show examples of two common venting mistakes made
in garages. The photo on the left above shows a clothes dryer exhaust vent
emitting moisture into a garage. The moisture was forming invisible
condensation on the walls, ceiling, and OSB sheathing behind the exterior
siding, which was then causing mold to germinate and grow on all of those
materials.
The photo on the right shows a similar situation where an air register from
a house furnace is installed in a garage. Prior to concerns over energy
conservation this used to be a common practice in homes to supply
moderate heat to the garage. However, building code did not allow air
return registers to be installed in garages (and rightly so) due to the
potential for carbon monoxide from automobiles to enter a home through
them.
What was not considered was that this arrangement essentially makes the
supply register an exhaust fan that depressurizes the interior of the house
resulting in negative indoor air pressure every time the furnace or air
conditioner runs. Negative indoor air pressure, due to any cause, has its
own long list of consequences, which is why I encourage you to read the
book How Indoor Air Pressure Can Make You Sick.
The other issue that was not taken into consideration was the humidity in
the air coming out of the air supply register, which condenses on garage
walls, germinates, and spreads mold.
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Overhead door mold
A garage door is often the coldest surface in a garage. Because of this,
moisture vapor in garage air will migrate to the garage door, which then
causes dust particles to stick to it, which then results in mold germination
and growth.
Trash cans
Most garbage contains food for mold, and when mold is inside a trash can,
it can grow 24 hours a day. Thus, when a person drops a new bag of trash
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inside the can, they are instantly and acutely exposed to countless mold
spores that are simultaneously pushed up and out of the can. They might
have an immediate reaction to the mold, but most symptoms are
experienced shortly after walking away from the trash can, which can make
it hard to identify exposure to the mold in the can as the cause.
Attic inspection
In addition to garages, I want you to understand attic spaces and why they
can become hotbeds for mold contamination.
I discover mold growth in attic spaces of many homes. The mold is often
unbeknownst to the occupants until the rare occasion when someone
enters the attic and sees it, or when a home is being sold and a home
inspector or appraiser finds it.
Even though attic mold is technically outside the occupied area of a home,
spores from that mold can intermittently affect the air in the rest of the
house by passing down through points of air leakage between the attic and
the occupied space below.
When inspecting an attic it is important to have someone with you in the
event of an emergency. If you intend on using a ladder to view an attic
through an access on a ceiling or high up on a wall, I also recommend that
you go to www.osha.gov and learn about ladder safety.
You’ll need a bright flashlight and/or headlamp to effectively see in a dark
attic. And if you’ll actually be climbing into an attic space, I also recommend
wearing gloves to prevent slivers in your hands when hanging onto framing
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lumber. If you bring your camera up there, be sure it is strapped around
your neck so you do not lose it. Or, if you use a phone camera, be careful
not to drop it, because it can be difficult to find if it falls down into the
insulation.
In addition, never open an attic access or enter an attic without first putting
on a respirator mask. Even without a mold problem, many types of attic
insulation are known to be irritants. Many attics also have contaminants
from insect, mice, bat, squirrel, bird, snake, and raccoon infestations. And
of course if mold is present, you need to protect yourself from that
contaminant as well.
Before I show you what goes on inside an attic space, I want to teach you
about the accesses between the house and the attic, because they are very
often the cause for problems up in an attic.
Attic access
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The first rule with attic accesses is that you need to have one. The photo
above shows a house with no attic access but with an obvious moisture
problem up inside the attic, as is evidenced by the anomalies on the ceiling.
Every attic should have an access to allow for periodic inspection and
corrections of deficiencies. If one is not present, you should have one
installed.
Before opening the attic access panel, you should inspect it for possible
water damage or urine stains from vermin.
Water damage around an access panel is usually caused from warm
moisture‐laden indoor air exfiltrating around the panel. However, the
stains might be caused from the urine or excrement of mice, squirrels, bats,
and/or raccoons.
The panel should be slowly pushed upward and off to the side without
spinning or flipping it so that you remember how to reinstall it in the same
position.
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Many attic accesses have wall panels installed around the sides of the
opening called insulation dams. They prevent insulation from falling down
into the house when the access is opened. If your access does not have
these panels, you might be surprised when insulation falls all over you. This
is another reason why you want to open the panel slowly and have a mask
on.
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Once the panel has been removed you want to inspect around the outer
edges were the access panel normally sits to see if there are accumulated
dust particles. Because house dust has weight, it usually settles downward,
so when you see dust particles around the access you know it was sucked
upward. This means air from the house has been escaping into the attic. If
that air has moisture in it and the attic is cold, there is a good possibility
mold will begin growing in the attic.
Water stains or peeling paint on the insulation dams is another indication
of air leaking up into an attic.
Insulation that sits on top of access panels that has mold or discoloration
from house dust is another indication that significant amounts of air have
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been leaking from the house up into the attic space. It also indicates
possible mold growth in the attic.
When humid air from a house has been leaking up through an access panel,
the moisture can condense on the insulation dams, not only causing water
stains or peeling paint but also significant amounts of mold growth on the
panels. Then, when the air pressure changes and the air passes from the
attic back down into the house, for instance when a clothes dryer is sucking
air out of the house down below, mold spores can be pulled down into the
occupied home below.
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Attic access panels and doors that enter into attic spaces through sidewalls,
stairways, or pull‐down stairs essentially have all these same hidden issues,
so be prepared.
This is probably a good time to mention that the remedies for mold and
moisture problems are provided in the book Do‐It‐Yourself Mold Cleaning
& Prevention. The purpose of this inspection series is to help you
understand how and where to inspect your house for mold.
When mold grows in attics it can grow within insulation, on the tops of
ceilings as viewed from the attic space, and on rafters, but it most
commonly grows on wood sheathing underneath roof shingles. The
sheathing can consist of OSB, plywood, and wood boards, any of which will
be visible from within the attic space.
Roof leakage
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While roof leakage is common, mold growth as a result of that leakage is
far less common because liquid water typically dries out between
incursions, whereas moisture vapor can linger for long periods of time.
When mold does grow as a result of leakage, it will usually be in isolated
areas, making the cause obvious, as shown in the photo above.
Attic venting
Air must flow into and out of an attic for the space to be properly
ventilated and eliminate moisture. Very often vents are blocked, however,
which can result in attic moisture and mold problems.
The photo on the left above shows the attic side of an air intake soffit vent
that is partially blocked with insulation. Often these vents are entirely
blocked with insulation.
The photo on the right shows what is called a chute vent, which allows air
from a soffit to pass through the chute and enter the attic. These are
required by code when insulation is added to an attic space to prevent
blockage of the soffit intake vents, but they do no good when an insulation
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contractor fills them full of insulation, as shown by the arrow. Both of these
conditions can cause mold growth in attics, as shown on the underside of
the roof in the photo on the right.
Some roofing contractors cut corners by covering exhaust vent openings
with underlayment and shingles and then not installing new replacement
vents like they are being paid to do. Another common mistake they make is
installing new ridge vents up at the peak of the roof but not cutting the
ridge open as they are supposed to do to allow heat and moisture to exit
the attic. Both of these mistakes eliminate an attic’s ability to get rid of
moisture, which can result in mold contamination problems.
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Roofing contractors also mismeasure and then do not center the vents over
the tops of the roof openings, thereby significantly reducing their ability to
provide adequate exhaust ventilation.
Ridge vents that are commonly used in new construction and roof
replacements have fabric on the underside of them. Even when these vents
are installed correctly, the fabric can collect dust particles as air passes up
and through them, no different than an air filter. The particles eventually
stop air flow and the ability of the attic to eliminate heat and moisture‐
laden air. They can also support the growth of mold, as shown above.
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Appliance venting
Today air ducts from clothes dryers and kitchen and bathroom exhaust fans
are required to vent to the outdoors. There was a time when they were
allowed to vent into attic spaces, but this was never a good idea. There are
still do‐it‐yourselfers and corner‐cutting contractors who continue to try to
get away with this, but doing so is asking for a mold contamination problem
in an attic.
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Simply hanging an air duct near an existing vent as shown in the photo on
the left is not sufficient. The damp air coming out of the duct will follow the
path of least resistance, which means it will stay in the attic space where it
can condense on all of the wood near the end of the duct.
Air ducts should also be attached securely to a roof damper so they don’t
fall off and cause attic mold to grow, as shown in the photo on the right.
Air leakage
In most instances when attic mold is spread over a wide area on the
underside of a roof, it is due to significant amounts of moisture‐laden air
leaking up into the attic from the house below. The points of leakage can
include attic accesses as shown above, as well as electrical junction boxes,
sill plates on the tops of interior walls, gaps around chimneys, and exterior
walls. Usually you can see mold or discoloration within insulation at the
points of air leakage.
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The photo on the left above shows insulation that is directly above an
interior wall and discolored with house dust and mold growth. The photo
on the right shows the same around a bathroom exhaust fan.
In the pair of photos above, the one on the left shows mold on insulation
due to air leakage through a hole where electrical wiring was fished down
into an interior wall. The photo on the right shows discolored insulation
around an electric junction box used for a light fixture.
Gaps around plumbing pipes and chimney penetrations through attic floors
are also significant points of air leakage into attics that can contribute to
mold growth.
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The photos above show mold caused by moisture‐laden air entering attic
spaces after passing through insulated exterior walls.
In cold climate regions, the undersides of roofs will frost up from excessive
moisture in attics. The process begins with ice balls that develop on nails
that protrude through the roof because the metal nails are efficient
thermal conductors.
I was called to investigate one home where the clients told me that they
had water coming out of all their light fixtures. When I inspected the attic I
discovered a quarter‐inch of ice on the entire underside of the roof
sheathing that had slowly accumulated during cold weather and then
began melting quickly when the weather warmed up.
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The photo on the left above shows elongated black spots where shingle
nails protrude through the underside of the roof. These stains or rusty nails
are a direct indication of excessive moisture trapped in an attic space, as
well as an indication that the home is about to have an attic mold problem.
The photo on the right shows circular black spots on the underside of a
roof. If you see these black spots in an isolated area while all the other
wood appears clean, then you are likely looking at mere splattered ink,
which occurs at the lumber factory as they print required identification
labels on their wood products.
Attic mold, on the other hand, is often discovered over much larger areas,
as seen in the photos below, including on the undersides of roofs, rafters,
and sidewalls, and sometimes extending down into soffit areas. As I’ve
mentioned, these conditions can occur when high levels of humidity are
trapped inside an attic space. And they can occur in attics that have walk‐
up stairs, as well as attics with ceiling or sidewall access panels. Mold can
also grow unseen inside attics that have no access at all.
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Vermin
Sometimes nesting materials from bees, wasps, mice, and birds are
discovered inside the attic vents, which prevent them from functioning
properly, thereby trapping moisture in the attic space.
In some instances critters find ways to enter attics through vents to find
safe and comfortable places to live and raise their families. The photos
above show evidence of squirrels and birds that made their way into attics.
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The photo on the left above shows evidence of squirrels chewing nuts and
tunneling in insulation, and the photo on the right shows what mouse
tunnels look like in a mice‐infested attic. Not only can squirrels and mice
initiate mold problems in attics, but their elimination materials can also
cause health issues. Additionally, they chew electrical wiring which can
start house fires.
The photos above show a bat roosting in the upper area of an attic and bat
guano on attic insulation.
I showed you these examples of vermin infestation in attics because the
elimination materials, odors, and associated mold growth from all vermin
can cause health issues for those living inside houses below.
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When I discover vermin in homes, I find that almost all of the homeowners
are unaware of the problem. For this reason, you may want to read
Unwelcome House Guests, available at IndoorAir.com, which explains the
most common vermin, how they get into homes, where they hide, the
damage they can cause, and how they affect your indoor air quality and
health. The book also includes practical solutions to eliminate vermin
without hiring an exterminator, as well as measures to prevent recurrence.
Do‐It‐Yourself Mold Inspection is a ten‐part book series. The next book in
the series is Part Four: Kitchens & Bathrooms. These rooms have food
items, bio‐matter, plumbing fixtures, and high moisture generation. You
will be surprised at how many different locations mold grows in in these
rooms, and I can assure you that after you read the book you will find mold
in some of those areas in your own home.
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Helping others
If you enjoyed learning from this book, I’d like to ask you to help your
family and friends. Just email them the IndoorAir.com link or post it on
your favorite social media space so they can see the educational resources
available and download their free copy of Six Steps to Healthy Indoor Air.
All the books were written to help people who are concerned about (1) the safety and health of their families and pets, (2) saving energy,
(3) safeguarding the value of their homes, and (4) protecting
themselves from being scammed by contractors, home sellers,
landlords, insurance companies, and those who work with mold or air
quality.
The books are based on decades of field work and are packed with inspection photos to show readers exactly what to look for in their
own homes and workplaces. Readers promptly get the help they need
no matter where they live and for far less than the cost of an
inspection.
Thank you for sharing the link. If you would like information on air
purification systems, just email me at dan@indoorair.com.
Thanks,
Dan
© Copyright 2017 Indoor Air LLC, All Rights Reserved
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