- Water is the main cause of fungal growth in homes. Many common problems like poor roofing, siding issues, lack of drainage, sprinklers too close to the home, and plumbing or AC leaks can provide water for fungi to thrive. - Homeowners should regularly inspect for issues that may provide excess moisture, such as deteriorating roofs, siding, caulking and flashing, clogged gutters, overgrown vegetation, and poor drainage around the property. - Any gaps, holes or unsealed areas in a home can allow water intrusion and fungal growth, so maintaining proper seals and drainage is important to prevent fungal growth issues.

1. You Can Make Your Home A Do-it-yourself Fungi Farm
By Stephen Ruback, Professional Inspector [TREC License 6030]
Nothing to it. As we discussed in the previous a two inch gap between any siding on a vertical
Fungi article, water is always the culprit. Our wall and the shingles on an adjacent roof. That way
cellulose culinary banquet, called a house, only the siding doesn’t soak up water from the bottom
needs a little water to activate the growth of every time it rains. Odds are very high if you have a
potentially hundreds of thousands of varieties of vertical side wall adjacent to a roof, yours doesn’t
fungi, 24/7. So where would that water come from? have it.
Let us count some of the ways. Flashings are there to keep water from getting
into penetrations – places where there is an
Roof covering intentional hole – like for plumbing pipes, doors,
Most people wait until the raindrops are falling and windows, etc. It amazes me how many
on their head before considering a new roof. By flashings are not sealed. What you don’t see can
that time your fungus farm is probably well under hurt you.
way in your attic. Take a close look at your roof at
least a couple times a year. Are your shingles still Gutters
covered with those tiny pieces of gravel or is the When not working properly, they can be a very
sun devouring the last vestiges of water repellancy? destructive force. When installed correctly, kept
How old is it? More than 15 years and it is time to clean and in good condition, they help keep water
start budgeting for a new one. What about those off the walls. They also keep rain water off your
trees dragging their branches across your roof in the head at entrances.
wind, could they cause some damage to the roof
covering? Uh-Huh. And always check your roof Vegetation
after a storm, hail yes! If you don’t know what to Some places resemble a jungle with all kinds of
look for, consult with someone who does. vegetation crowding around. Plants suck water out
of the ground and send it out of their leaves, all the
Wall coverings time. They also block the sun, helping trap moisture
Countless houses have that nasty old fiber siding inside walls. Too much vegetation can eat a wall in
that dissolves when wet. Many others have some less than two years.
sort of wood siding that is little better. If it is not I was called to look at a wall problem. The home
well protected by a good paint and caulk job, it is was about ten years old. There was a long brick
already an active fungi museum. That black or wall extending half way down the drive. Between
colorful stuff peeking out from the corners and the wall and the drive was a veritable wall of
cracks is not your friend. bushes, nice and thick from the ground, all the way
Holes of any sort let water into the dark hidden to the soffit. The bushes were manicured and gave
areas for secret societies of mold and fungi to thrive the impression of attentive home maintenance. The
and multiply. Water trapped in your walls creates owner had noticed some black stuff along the
perfect growing conditions. Ever notice those little baseboard of the bathrooms which were part of that
gaps at the bottom of your brick walls? They are outer wall. The baseboards had already been
called weep holes, and are supposed to be there. replaced once before. This time the soft spots inside
They let moisture out. Don’t ever plug them. If they the wall were too great for the nails to stick. The
are missing, your walls are well on their way to wall was opened from the inside to see what was
becoming a fungi farm. going on. The bushes had done a fabulous job of
Inside, wall coverings can also be a problem. holding in the moisture and the bottom two feet of
Vinyl wall paper is especially troublesome in wet wall structure was virtually gone. Your house needs
areas. Moisture gets trapped behind it and guess breathing space.
what grows there? You won’t see it ‘till you pull
the wallpaper. Fungi love the paper on the Flower beds
wallboard and the glue. Give it enough water and it When building a house, someone makes the
can grow right through the wallboard. Any gap will effort to establish a slope away from the house for
do for moisture. drainage. Then the landscape people come and pile
dirt in front so that any water within ten feet of the
Flashings and trim front will drain right back to the foundation. Later
It’s bad enough to have holes big enough for on, people wonder whys they have foundation
critters to enter, but water can come in the smallest problems.
openings. It can easily ooze down around unsealed It gets even more exciting when they stick those
nails, into the dark, sweet spots. If you give it right itty-bitty bushes up against the house. No one
sized gap, it can even move up hill. Porous surfaces seems to notice that they typically plant some sort
suck it up. That’s why siding manufacturers call for of variety that can grow higher than the house in a

2. few seasons. Then they pile mulch all over the Corroded connections also insure a supply of leaks.
mound, several inches thick.
Lets see now, mulch is usually chopped wood. It Sewer leaks
is piled in heaps under growing plants all around Old cast iron drains are especially prone to
the house. Every time it rains, every kind of fungus leaking under houses. With this kind of leak you
in the area is treated to a veritable paradise. On the can get a whole lot more than just a fungi farm.
North side, where the sun doesn’t reach, it is These drain lines can be tested.
paradise all the time. By the way how sensible is carpet in bathrooms?
What a wonderful environment for all of our fungi
Built-in flower boxes friends to prosper and multiply.
These were all the rage, years ago. Could their
decline in popularity be associated with their AC systems
tendency to rot out the adjacent walls in short order. We bring humid air into this cool dark place
If water can get in, it will. Plentiful food and shelter where water literally drips out and send it down the
is already there, all your fungi needs to raise a big duct at close to 100 % humidity, right back into the
family is a little water. living space. Sure it’s cool, but fungus does not die
in cool temperatures, it just slows down. Even slow
Sprinklers growth 24/7 can be noticeable. We seem to enjoy
We build our houses out of gingerbread, then feeding our fungi plenty of dust along the way.
surround them with plants. Just to be sure we never When was the last time you had your internal fungi
run short of fungi, how about spraying water on the farm thoroughly checked?
sides of the house every day or so, whether it rains
or not? That’ll keep our fungi farm healthy and Closed rooms
prosperous. Never close off a room for more than a short
period of time – especially in warm, humid
Poor drainage climates. With no air circulation or active moisture
Think of concrete as a rigid sponge. It loves to removal you convert the room to a fungi recreation
soak and wick water upward, sideways – any which hall and free unlimited buffet.
way it can. When we place a nice little pool, a If the house is empty, you can quickly convert
convenient low spot that collects water every time the whole building to a superb fungi feast just by
it rains, or perpetual wet spot, say from the AC turning off the AC, to save a little electricity. As the
condensate drain discharge, next to the wall, what humidity and temperature climbs, your fungi
happens? Presto, another fungi farm inside the wall, friends will love it.
guaranteed.
If there was one sound byte to remember, it
Windows might be,“It’s the moisture, stupid!”
Windows are holes in your wall. Virtually all Every home needs a thorough inspection.
windows leak, at least somewhat. Few windows
have great flashing. Older windows probably have Stephen Ruback is a licensed Professional Inspector;
none. We depend primarily on caulk to keep the approved by TREC as a Professional Home Inspection
water out. Why is it that few people seem to pay Instructor. Website: www.sruback.com
any attention to their caulk joints? Rotted wall In addition, he has earned a BS in engineering from Trinity
sections under windows are very common. The University, is an author of several books and teaches a
fungi that live there love it. variety of self empowerment courses. For more information,
he can be reached at 832-489-1071.
Porches and overhangs
Whenever we have wood sticking out from the
side of a wall, we invite water into the joint and the
exposed wood. Proper flashing is almost never
done at these junctions. Every time it rains the
fungi have a ball in the wall.
Plumbing leaks
They can be anywhere. Most common leaks are
at connections. That nice, dark, cozy, seldom
visited place under the kitchen sink is probably the
most popular fungi farm in the nation. When was
the last time you turned off all the water in your
house [including the ice maker], made a note of the
dial position at the water meter, then checked it
again several hours later? Any movement means
fungi is growing somewhere in you home.