The Condominium Owners'
Guide to Mold
Understanding molds
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mold can be harmful or
helpful - depending on where it grows.
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mold needs moisture to
grow.
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mold does not grow on dry
materials.
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mold growing inside a condo
can affect the occupants.
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occupants can learn to
recognize mold
What are molds?
Molds are microscopic fungi,
a group of organisms which also includes mushrooms and yeasts. Fungi are
highly adapted to grow and reproduce rapidly, producing spores and mycelia
in the process.
You
encounter mold every day. Foods spoil because of mold. Leaves decay and
pieces of wood lying on the ground rot due to mold. That fuzzy black
growth on wet window sills is mold. Paper or fabrics stored in a damp
place get a musty smell that is due to the action of molds.
Molds can be useful to
people. The drug penicillin is obtained from a specific type of mold. Some
foods and beverages are made by the actions of molds. The good kinds of
molds are selected and grown in a controlled fashion.
Molds are undesirable when
they grow where we don’t want them, such as in homes. Over 270 species of
mold have been identified as living in Canadian homes. Molds that grow
inside may be different from the ones found outdoors.
What makes molds grow?
Molds will grow if we provide
them with moisture and nutrients. If we keep things dry, molds do not
grow.
High moisture levels can be
the result of water coming in from the outside, through the floor, walls
or roof; or from plumbing leaks; or moisture produced by the people living
in the condo, through daily activities like bathing, washing clothes or
cooking. Water enters the building when there is a weakness or failure in
the structure. Moisture accumulates within a condo when there is not
enough ventilation to expel that moisture.
Different kinds of molds grow
on different materials. Certain kinds of molds like an extremely wet
environment. Other kinds of molds may be growing even if no water can be
seen. Dampness inside the material can be enough to allow them to grow.
Why are molds a concern?
Damage to materials is one
concern. Materials get stained or discoloured, and over time they are
ruined. Moldy paper and cardboard disintegrate over time. Fabrics are damaged.
Continued mold growth can be indicative of moisture conditions favorable
for growth of fungi that cause wood rot and structural damage.
When molds are growing inside
the home, there may be health concerns. Molds release chemicals and
spores.
Health experts indicate that,
depending on the type of mold present in a home, the amount and degree of
exposure, and the health condition of the occupant, the health effects of
mold can range from being insignificant to causing allergic reactions and
illness.
Pregnant women, infants, the
elderly and those with health problems, such as respiratory disease or a
weakened immune system, are more at risk when exposed to mold. Consult
your family physician if you believe there is someone who may be at risk.
How can you tell if it is
mold?
Discolouration
Discolouration is a sign of
mold. However, all discolouration is not due to mold. Carpeting near
baseboards, for example, can be stained by outdoor pollution entering the
home. Stains or soot may also be caused by the smoke from burning candles
or cigarette.
Mold may be any colour :
black, white, red, orange, yellow, blue or violet. Dab a drop of household
bleach onto a suspected spot. If the stain loses its colour or disappears,
it may be mold. If there is no change, it probably isn’t mold.
Smell/Odour
Sometimes molds are hidden
and cannot be seen. A musty or earthy smell often indicates the presence
of molds. But a smell may not be present for all molds. Even when you
don’t notice a smell, wet spots, dampness or evidence of a water leak are
indications of moisture problems and mold may follow.
When is mold a problem?
-
estimate how much mold is
growing.
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you can clean up a “small
area” of mold yourself.
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for larger mold areas or
recurrent mold problems, seek professional help.
Is there a mold problem?
Molds are always found in the
air outside and in all buildings. They come into the home in many ways
-through open windows or doors, on clothing, pets, food or furniture. The
problem starts when mold grows inside the unit.
Some mold growing, for
example on the window sill but not elsewhere, is not a cause of concern.
You can clean the mold yourself. The presence of mold is a sign that there
is too much moisture in your condo - a situation which must be corrected.
Mold
that is isolated inside walls and which cannot easily come in contact with
the occupants is less of an immediate concern but should be dealt with by
the Condominium Board.*
Inspect the condo to find the
extent of the mold. Advise your Condominium Board if you suspect a serious
mold problem.
How much mold is growing?
One way is to estimate the
area of the mold.
Mold is considered to cover a
“small area” if it is no larger than the size of a standard garbage bag
folded in half (crosswise or lengthwise). If there is another mold patch
beyond two garbage bag lengths away it is considered a separate patch
(otherwise it all counts as a larger patch). Clean up small areas yourself
using a detergent solution, household rubber gloves and a dust mask for
protection.
Small moldy areas may become
larger over time if ignored, so it’s important to clean up and remove even
small patches of mold.
If the patch of mold or all
nearby patches (less than two garbage bag lengths apart) combined are
larger than a garbage bag folded in half but smaller than a 4 x 8 foot
sheet of plywood or drywall, the mold area is considered “moderate.” You
can clean up moderate amounts of mold but you must follow the proper
procedures and use the proper protective equipment.
A mold area is considered
“extensive” if a single patch of mold is larger in area than a sheet of
plywood. Being exposed to this much mold is not a good idea. Do not
attempt to clean up large areas of mold yourself. You need professional
help to determine why the mold is there in the first place and how to
clean it up.
When should you seek
professional help?
You may need professional
help when:
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there is an extensive
amount of mold;
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the condo is very damp and
moist;
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mold comes back after
repeated cleaning; and
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a family member suffers
from asthma or respiratory problems or other health problems that appear
to be aggravated inside the condo.
How do you get professional
help?
Advise your Condominium Board
of mold problems you may be experiencing. Your Condominium Board will
determine if envelope specialists should be consulted to resolve moisture
ingress through the envelope.
You may wish to seek advice
on how you can improve your own unit. Contact your local CMHC office for a
list of individuals who have completed the CMHC Residential Indoor Air
Quality Investigator program. A trained IAQ investigator, who operates a
private business and sells his/her services, examines the inside indoor
air quality conditions of your condo and documents your concerns. He/she
identifies the problems, finds their sources and suggests solutions in a
written report. Recommendations are provided to you in an action plan that
consists of various options to improve the indoor air quality in your
home.
Ask your Condominium Board
for names of mold clean-up contractors -individuals who have been trained
to clean up mold.
How to clean up small mold
problems
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“small areas” of mold can
be cleaned with a detergent solution.
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wear a mask, safety
goggles, rubber gloves and a long-sleeve shirt.
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seek professional help if
there is a lot of mold or if mold comes back after cleaning.
“Small area” clean-up
You can clean up “small
areas” of mold (less than the area covered by a garbage bag folded in
half) yourself. The minimum protective wear needed is:
-
safety glasses or goggles;
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a disposable dust mask (3M
8210 or equivalent);
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household rubber gloves;
and
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long-sleeved shirts and old
clothes.
Occupants with asthma,
allergies or other health problems should be out of the unit during the
cleaning.
Steps to follow in cleaning
up small mold areas
Washable surfaces
Scrub with a detergent
solution; then sponge with a clean, wet rag and dry quickly.
Moldy drywall
Clean the surface with a damp
rag using baking soda or a bit of detergent. Do not allow the drywall to
get too wet.
Mold that comes back after
cleaning is usually an indication that a source of moisture has not been
removed. Seek professional help from a trained IAQ investigator.
How to clean up moderate
mold problems
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clean “moderate areas” of
mold, but wear proper protective equipment and follow precautions.
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notify your condominium
board of remediation steps in your own unit.
-
seek professional help if
there is a lot of mold or if mold comes back after cleaning.
If you follow the proper
procedures and use the proper protective equipment, you can clean up
“moderate areas” of mold. “Moderate” means the patch of mold or all nearby
patches (less than two garbage bag lengths apart) combined is larger than
a garbage bag folded in half but smaller than a 4 x 8 foot sheet of
plywood.
a) Safety precautions
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Wear a half-face respirator
with charcoal cartridges, safety goggles, heavy-duty rubber gloves,
disposable coveralls and head covering, and washable boots.
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Isolate the area to be
cleaned with plastic sheeting, taped to walls and ceiling.
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Family members at higher
risk should not be in the work area during the clean-up.
b) General cleaning
Vacuum surfaces with a vacuum
cleaner which has a High Efficiency Par ticulate Air (HEPA) filter or is
externally exhausted. Scrub or brush the moldy area with a mild detergent
solution. Rinse by sponging with a clean, wet rag. Repeat. Dry quickly.
c) Cleaning wood surfaces
Vacuum loose mold from wood
surfaces using a HEPA or externally exhausted vacuum. Try cleaning the
surface of the wood with detergent and water. Rinse with a clean, damp rag
and dry quickly. If the staining does not come off, sand and vacuum the
surface of the wood with a vacuum/sander combination. It is important to
vacuum at the same time to prevent mold spores from being dispersed into
the air. Note that wood affected by rot may need to be replaced.
d) Cleaning concrete
surfaces
Vacuum the concrete surfaces
to be cleaned with a HEPA or externally exhausted vacuum cleaner. Clean up
surfaces with detergent and water. If the surfaces are visibly moldy, use
TSP (trisodium phosphate). Dissolve 1 cup of TSP in two gallons of warm
water. Stir for two minutes. Note: TSP must not be allowed to come in
contact with skin or eyes. Saturate the moldy concrete surface with the
TSP solution using a sponge or rag. Keep the surface wetted for at least
15 minutes. Rinse the concrete surface twice with clean water. Dry
thoroughly, as quickly as possible.
e) Moldy drywall
The paper facings of gypsum
wallboard (drywall) grow mold when they get wet or repeatedly wet and
don’t dry quickly. Cleaning with water containing detergent not only adds
moisture to the paper but also can eventually damage the facing. If the
mold is located only on top of the painted surface, remove it by general
cleaning (above). If the mold is underneath the paint, the moldy patch and
other moldy material behind it are best cut out and the surrounding areas
also cleaned. This should be done by a mold clean-up contractor. New
materials may become moldy if the moisture entry has not been stopped. If
this is the case, replacement of the materials should be deferred until
the remediation of the building is completed. The affected areas should be
temporarily covered with plastic sheeting and sealed at the edges.
Any areas that show new
patches of mold should be cleaned promptly.
Notify your Condominium Board
of the extent of mold in your unit.
Dealing with an ongoing
problem
Repair to the building
envelope is required if moisture is entering the unit from the outside.
Your Condominium Board may already be undertaking the work or is in the
process of preparing to carry out the remediation. Condominium owners,
meanwhile, can take steps to reduce their exposure to mold in their own
units.
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Discard moldy or damaged
materials.Wear a dust mask and gloves. Furnishings, such as mattresses,
carpets, or sofas that got wet or have been stored in damp conditions
should be discarded. Discard items that are no longer needed. Clothes
and other items that have been cleaned should be stored in sealed
plastic bags to prevent re-contamination.
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Proper vacuuming reduces
the amount of mold spores. All surfaces in the condo (floors, walls,
ceilings, shelves) and non-washable furnishings (such as sofas, chairs,
etc.) must be vacuumed thoroughly.
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Keep moisture generated
within the unit to a minimum by conscientiously following the prevention
steps.
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Pull carpets and
furnishings away from walls that get wet. Carpets and underpads that are
moldy should be cut out and discarded.
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Take steps to dry up areas
that get wet. Monitor the relative humidity of the air. Use a portable
dehumidifier, if necessary. Ensure that the condensate drain pan of the
dehumidifier is emptied regularly.
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If the mold is limited to
one area, isolate the area if possible. Cover the affected surfaces with
plastic sheeting secured at the edges with duct tape. Note that this is
only a temporary measure to minimize your exposure.
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Healthy individuals can
regularly clean “small” and “moderate” areas of mold, thus preventing
these from getting out of hand, by following the safety precautions and
cleaning guidelines.
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Consider seeking
professional help from trained IAQ investigators to identify appropriate
remediation steps inside the unit. Removing large amounts of mold will
require the services of mold clean-up contractors.
Preventing mold
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Keep the condo dry.
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Find and fix water leaks.
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Discard clutter and excess
stored materials.
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Clean and maintain the
condo regularly.
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Encourage lifestyle
practices that reduce moisture.
Basic steps to prevent and
reduce mold growth
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Mold needs moisture to
grow. Controlling the moisture and keeping the condo dry prevents the
growth of mold.
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Check your condo for signs
of moisture and molds.
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Find out if water is coming
in from the outside and if substantial moisture is produced inside the
condo.
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Report any water leaks,
moisture or molds to the Condominium Board promptly.
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Think of the different ways
moisture is produced inside the condo (for example, cooking, bathing,
numerous indoor plants). Remove the moisture as it is produced by using
exhaust fans. In the absence of fans, open windows for a short time, but
note that the wind can push the moisture to other parts of the condo.
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Measure how much moisture
is in the air. To find the relative humidity in your home, you’ll need a
hygrometer. You can buy one at a hardware store or electronics store. A
hygrometer costs from $5 to $20. Relative humidity in the home should be
under 50%. If necessary, use a dehumidifier to lower the relative
humidity.
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Reduce the amount of stored
materials, especially items that are no longer used. Molds grow on
fabrics, paper, wood and practically anything that collects dust and
holds moisture.
Mold-proofing your
condominium, room by room
Basement
or crawl space
(Note: Although this section
was written for homeowners, some of the principles would also apply to
basements in condominium buildings. Communicate with your Condominium
Board.)
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Reduce the amount of
clothes, paper and furnishings stored in the basement. Discard badly
damaged materials. Eliminate clutter to improve air circulation. Only
washable items should be stored.
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Avoid carpets on
slab-on-grade or below-grade floors.
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Periodically clean the
drain in your basement floor. Use half a cup of bleach, let it stand for
a few minutes, then flush with plenty of water. Keep the drain trap
filled with water.
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Avoid standing water. Keep
sump pits covered (you can use plywood wrapped with plastic).
Furnace room
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Regularly clean and replace
furnace filters. Use a pleated one-inch filter, not a coarse filter.
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If you have a heat recovery
ventilator (HRV), clean the filter inside the HRV often.
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If you notice molds or
signs of dampness, such as water on your windows or wet spots elsewhere,
do not humidify.
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Disconnect furnace
humidifiers that are no longer used.
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If you have electric
baseboards, vacuum the units, or have a professional clean them for you.
Laundry areas
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Check that your clothes
dryer exhausts to the outside.
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Remove lint every time you
use the dryer.
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Don’t hang-dry laundry
indoors.
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Dry your laundry tub and
washing machine after you use them.
Bathrooms
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Check the bathroom fan to
make sure it exhausts to the outside.
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Turn the bathroom fan on
when you shower. Keep it running for a few minutes after you finish your
shower.
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Take short showers.
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Keep surfaces that get wet,
such as the walls around the bathtub and shower, clean and dry.
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If there is a carpet in
your bathroom, remove it.
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Check for water leaks.
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Keep drains in good shape
by removing debris from them.
To clean a drain:
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Pour a handful of baking
soda into it.
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Add a cup of vinegar.
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Put the plug in the drain.
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Let the vinegar and baking
soda work for about 20 minutes.
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Run fresh water into the
drain.
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If the drain is still
clogged, use a small plumbing snake.
Kitchen
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If the fan over your stove
exhausts outside, use it when you cook.
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Minimize open boiling.
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Keep your drains in good
shape. Follow the steps in the Bathroom section above.
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There’s a drip pan at the
back of your refrigerator. Pull the refrigerator out to clean the drip
pan. At the same time, vacuum dust from the coils at the back of the
refrigerator.
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Check under the kitchen
sink to make sure there are no leaks.
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Take out the garbage daily
to prevent odours and spoiling.
Closets and bedrooms
Other parts of the condo
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A dehumidifier helps to
reduce moisture in the condo during the warmer months. Close the windows
when the dehumidifier is running.
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When family and friends
come into the condo, have them take off their shoes.
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Vacuum often. If you are
buying a vacuum cleaner, try to get one with a HEPA filter (see below).
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Clean hard floors with a
damp mop.
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Do not bring into your
condo furniture, clothing, books, etc. that have been stored in a moldy
place.
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Cut down the number of
potted plants in the house – soil is a good place for mold.
Exterior
(Contact your Condominium
Board)
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Regularly check the
condition of the roof and exterior finish for any places where water
might enter.
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Make sure that eavestroughs
and downspouts are connected and working properly and that they are free
of debris.
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Install downspout
extensions to lead water away from the building.
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Deal promptly with any
problems that you find.
Frequently asked questions
about mold
The air feels dry - can I
humidify?
Before you add moisture to
the air, measure the relative humidity. Air that feels dry may not be
really dry. It may be moldy. High relative humidity (over 50%) promotes
the growth of molds and dust mites. The moisture in the air may condense
on colder exterior walls where molds start to grow.
If your physician has advised
you to use a humidifier in your child’s bedroom at night, monitor the
relative humidity. Turn the humidifier on and off as necessary. In the
morning, take steps to make sure the room gets dry. Clean and empty the
humidifier after each use.
What advantages do HEPA
vacuums provide?
Ordinary vacuums capture
large particles only - small mold spores pass through the vacuum into the
air. HEPA vacuums have special filters that capture small particles. A
central vacuum cleaner which is exhausted to the outside also removes mold
spores. A regular portable vacuum is useful only if its exhaust goes
outside the home.
Vacuuming removes settled
dust that contains an accumulation of mold spores over time. Reducing the
settled dust reduces molds. Vacuuming with any vacuum cleaner (ordinary,
central or HEPA) stirs dust and mold during the process. Wear a dust mask
so you will not be breathing more mold.
Is vacuuming with a HEPA
or externally exhausted vacuum cleaner recommended for serious mold
problems only?
Vacuum regularly with a HEPA
or externally exhausted vacuum cleaner to prevent the ongoing accumulation
of dust and molds. The need for HEPA or external exhaust vacuuming
increases with the severity of the mold problem.
If a furnishing has been wet
at some time in the past or has been exposed to dampness over a prolonged
period of time, vacuuming with HEPA or externally exhausted vacuum is
unlikely to remove the mold growing beneath the surface. It is better to
discard the item.
Where do you find a HEPA
vacuum cleaner?
Vacuum cleaner dealers carry
HEPA vacuums. Consider purchasing one as an upgrade to what you may be
using. A HEPA vacuum is a good investment in the long term whether you
have mold or not. A generic canister HEPA vacuum cleaner costs
approximately $300. Brand name products of the same type may cost more.You
may inquire if the dealer has a HEPA vacuum cleaner to rent. Contractors
who clean up or renovate houses for mold should also have this equipment.
Does painting over a moldy
surface take care of the mold?
Painting over mold only masks
the problem. Paint does not kill the mold nor stop it from growing.
Surfaces that are washable should be cleaned with a detergent solution,
following the procedure suggested on page 4, then allowed to dry. If you
are going to paint, remove any mold first.
Does cleaning stop the
mold growth?
Mold will reappear until its
source of moisture is removed. High moisture levels that are not corrected
can make the molds grow back quickly. Cleaning is only a temporary but
essential measure.
You can help by making a
conscious effort to keep the condo dry. For obvious reasons water must be
prevented from entering the condominium. But you can help by controlling
moisture that is produced inside the condo.
How does one clean clothes
that are moldy?
Non-washable clothing can be
dry cleaned. Wash clothes with a detergent solution to which a cup of
bleach is added. Make sure the detergent you use does not contain ammonia.
Repeat as necessary until the moldy odour is gone. Clothes and other items
that have been cleaned should be stored in sealed plastic bags to prevent
re-contamination.
Although
these information products reflect housing experts' current knowledge,
they are provided for general information purposes only. Any reliance or
action taken based on the information, materials and techniques described
are the responsibility of the user. Readers are advised to consult
appropriate professional resources to determine what is safe and suitable
in their particular case. CMHC assumes no responsibility for any
consequence arising from use of the information, materials and techniques
described.
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