Water
has damaged your carpets. Maybe you had a toilet leak, maybe your water heater
burst, maybe your kid left the faucet running in the sink for hours.
What
should you do to dry your wet carpet to minimize damage to your carpet and pad?
We
have Carpet Cleaning training, and over 10 years real world experience cleaning
carpets, drying flooded carpets and removing smells from carpets in all sorts
of situations - residential, commercial, thick pad, thin pad, no pad, berber,
cut pile, area rugs,etc.
First
of all, here's some basic information you should know that applies to all the
answer below.
Important Information about Water and Carpets
Residential
carpet usually has a pad underneath it. The pad can be anywhere from 1/4 inch
to almost an inch thick. The pad provides cushioning and gives your carpet that
comfortable, soft feel when you walk on it.
Commercial
carpet in offices and stores generally doesn't have pad underneath it.
Carpet
pad absorbs water like a sponge: The problem with pad under a carpet is that it
is a sponge and can hold many times its own weight in water.
Pad
is designed to cushion your feet, so it is spongy by nature and will soak up
water like the cleaning sponge in your kitchen sink.
Carpet
doesn't stop or hold much water: Although
your carpet may feel very
solid under your feet, it offers very little resistance to water passing through it.
Carpet
is actually like a sieve to water. A typical carpet will not hold more than a
few ounces of water per square foot of carpet before it is saturated. After
these initial few ounces of water have entered the carpet, any further water filters
straight through the carpet and into the pad.
Water
likes to travel: Water doesn't stay put. It travels. The rule to remember is
"Wet goes to Dry". Water will automatically move towards a dry
building material.
Water
at the center of a room will flow through the carpet and across the pad to the
walls. It will migrate to the edges of the room in a matter of minutes or hours
depending on how much water was spilled.
When
you touch the carpet at the edge of the room, it may not even feel damp, but
the pad could be saturated. This can be seen using an infrared camera. An
infrared (or Thermal Imaging) camera is useful in finding the real area that
the water has damaged, even if you can't see or feel it.
Below
is a floor layout showing a flood cleanup job. The red circle is the source of
the water - a broken toilet supply line.
The
blue areas are the areas with carpet that felt wet and the home owner was
worried about and wanted us to dry.
The
orange areas are the areas that were actually wet as shown by the infrared
camera and moisture meter.
The
top 'actual wet' area is tile and cabinets. Although there was no visible water
on the tiles, it had soaked through the grout and was under the tiles. The
cabinet was also wet. The lower 'actual wet' area is carpet and was found by
the infrared camera and confirmed with a moisture meter. You can't see it
clearly in the picture, but water had actually gone through the walls into
adjoining rooms.
Flood
cleanup. Orange areas felt dry but were actually wet.
The
picture below shows what a normal camera sees on the right The carpet looks and
feels dry. But it's not dry, it is wet.
The
infrared image on the left shows the pad underneath the carpet is wet. The
darker the area is, the wetter it is. You can see how the water has traveled
under the carpet along the wall. This is in the hall, 2 rooms away from where
the source of the water was.
Bearing
the information above in mind, here are some common myths about wet carpets and
how to dry wet carpets
Myth
#1. The carpet will dry by itself
This
is actually true, just like it is true that you could win the lottery with one
ticket.
Yes,
the carpet will eventually dry by itself. However, will it smell bad or have
mold on it by the time it is dry? What other damage will occur while the carpet
dries by itself?
Unless
you live in someplace like Arizona or the desert where you have high temperature
and low humidity, there is VERY little chance that the carpet and pad will dry
before mold starts growing or bacteria start creating that wet carpet, damp
smell. Typically you have about 72 hours to dry wet building materials before
they start growing mold.
Even
if the carpet itself dries, does that mean the pad is dry? There is very little
chance that the pad is dry. The pad holds more moisture than carpet and is
prevented from easily releasing the moisture due to the carpet above it and the
sub-floor below it. So even if your carpet is dry, the pad is probably not dry.
Which
brings us to another point. What about the wet sub-floor? Remember that carpet
is like a sieve, and the carpet will pass water down to the pad very quickly. A
saturated pad can then release water into the sub-floor.
Drying Sub-floors
Sub-floors are usually either woood or concrete.
Concrete
subfloors are sponges too, except they are very slow sponges. They absorb water
surprisingly quickly, but release it very slowly. So even if the carpet and pad
are dried quickly, the concrete sub-floor could still release moisture for
weeks.
Wood
sub-floors hold water too. If they're made of chip-board/particle
board/press-board (small chips of wood held together with glue) and they are
wet for more than a few hours they absorb water, expand, and lose their
structural integrity.
When
wet particle board dries it has almost no strength and you will find yourself
stepping through your floor if you're not careful. On
the right is a picture of wet particle board from a bathroom cabinet (I didn't
have a picture of particle board sub-floor, as it's not very common). You can
see how the board has disintegrated.
Plywood
or OSB (Oriented Strand Board) are much more hardy choices for a sub-floor than
particle board. If they get wet, you can dry them, as long as they haven't been
sitting wet for long enough to warp. This falls loosely under the 72 hour rule.
Another concern is dry rot which is a bacterial deterioration that takes 21
days to manifest at lower moisture levels.
Determining
whether the sub-floor is wet or not can only reliably be done with a
penetrating moisture meter as shown in the picture. Different building
materials have different acceptable levels of moisture, so you use the meter to
tell you if the material is acceptably dry or not.
Depending
on the region you live in, plywood is dry at around 20% Equivalent Moisture
Content (EMC).The picture shows perfectly dry looking and dry to
the touch
plywood.
However,
when the pins of the penetrating moisture meter are inserted, you can see that
the plywood is at 57% EMC, i.e. very wet. In as little as 4 days, mold can
start growing on this wood if not dried correctly. Chipboard
quickly disintegrates when wet.
So,
we know that the carpet and pad are unlikely to dry quickly enough by
themselves. But even if they did, is that all you have to concern yourself with
when your carpets are wet? No, it's not.Like
I said, WET goes to DRY. What this means is the water keeps spreading outwards
from the source. The picture below explains it. This is the same house that is
shown in the diagram at the top of this page. The pictures below are the area
at the top right corner of the big blue "Feels Wet" area in the
diagram at the top of the page. This is the door from the bedroom to the
bathroom.
The
carpet first got wet about 12 hours ago. During that time, the home owner used
her wet vac to suck up as much water as possible from the wet carpet - about
100 gallons.
However,
if you look at the infrared view of that area (the black and white picture on
the left) you will see that even though the water has been sucked out of the
carpet and has only been there for 12 hours, the water has wicked up the wall
about 6 inches.
Infrared
Image on the left shows wet drywall, while in the regular image on the right
the drywall appears dry.
Wet
drywall, what's the problem?
The
problem is the usual 72 hour problem.
In
as little as 72 hours mold can start growing on that wet dry wall. Mold
especially likes dark, warm places with no airflow. That describes the wall
cavity - the perfect place for mold to grow.So
that's the problem - wet carpet creates wet drywall which can create mold.
Below is a picture of a wall after water had been standing for a long time.
To
summarize. Yes, the carpet will eventually dry by itself. But you'll more than
likely have mold and smells by the time it is dry, and then you'll be ripping
walls and carpet out to fix the problem.
Myth
#2. You have to remove the wet pad underneath your carpet
There
is a myth that you can't remove water from a wet pad, even with
commercial
extraction equipment. People who say this are talking about the
standard carpet
cleaning 'wand' shown on the left. It is what is commonly used to clean
carpets. It sprays hot water onto the carpet and then sucks it back up again.The
wand is designed to pull water out of the carpet fibers, not the pad and it
does a good job at that. So if you have water damage on commercial carpet
without a pad, the wand is a good tool to use.
However,
on residential carpet with a pad, it extracts almost none of the water from the
pad.
So
how do you get water out of the pad so you don't have to remove and discard the
pad?
There
are a number of new commercial extraction tools that will remove water
from the
pad. Our favorite is the Xtreme Extractor shown on the right. It is a wonderful
piece of equipment.
Before
tools like the Xtreme Extractor came out, there was a technique called
"floating the carpet" which was used to dry carpet and pad due to the
poor job the wand did of extracting water from the pad.
To
float a carpet, you pull up a corner of the carpet and stick an air mover or
carpet fan under the carpet to blow air under the
carpet and onto the pad.
While this method still works it is slower, less effective, and often stretches
the carpet so that it doesn't fit properly when restretched.
Floating
the carpet is an old school technique that is unnecessary if you have the right
tools, ie a deep extraction tool such as the Xtreme Extractor.
To
complicate matters, bear this in mind. While you can dry wet pad, it doesn't
always mean you should.
If you have contaminated water in the pad you can dry it, but you will be leaving
at least some contamination in the pad and over time, it will start to stink
and rot. In contaminated water situations you will have to remove the pad
because you can't effectively decontaminate it while it is underneath the
carpet. In the water restoration industry, contaminated water is called
Category 2 (gray water) or Category 3 (black water).
Myth
#3. You can't dry a wet pad under a carpet
The
truth to this myth is the same as for the question above. Basically, you can
dry a wet pad, even without floating that carpet, but that doesn't mean you
always should. See the answer above for details.
Myth
#4. You have to lift the carpet and 'float' it using blowers
The
answer to this question is in the answer to question 2 above. To summarize, you
don't have to float carpet if you have a deep extraction tool and know how to
use it.
Myth
#5. You have to remove and discard wet carpet.
Sometimes.
If
you have a black water situation (Category 3 water - contaminated water such as
sewage, toilet leak or rising ground water), according to the industry standard
IICRC S500, you have to discard the carpet. I believe this is because there is
no EPA registered disinfectant for carpet.
However,
if you have Category 2 water (gray water such as washing machine waste water,
shower runoff,etc) you have to discard the pad, but you can clean the carpet
and keep it.
Category
1 water (clean water - toilet supply line, fridge ice maker, etc), and it
hasn't been sitting for more than 48 hours, then you can extract the water and
keep the carpet and pad.
The
other reason water damage restoration technicians sometimes believe they should
discard wet carpet is because the backing of the carpet will delaminate when it
is dried. The backing is the lattice webbing on the back of the carpet that
holds the carpet fibers together. It is glued on. If it gets wet and stays wet
for a long time it can separate from the carpet fibers and start to
disintegrate. How long is a long time? It's hard to predict - depends on the
carpet, the temperature, how wet it was, etc. Normally by the time the carpet
delaminates you've got a black water situation anyway, so the carpet has to go.
Myth
#6. Professional Carpet Cleaning will dry your carpet and pad
No.
Not unless they use a deep extraction tool that is designed specifically to
remove water from the pad. A regular carpet cleaning wand will not remove
significant water from the carpet pad.
Myth
#7. To remove the wet carpet smell, you should have it professionally cleaned.
Yes,
with a 'mostly' attached to it. The carpet cleaning machines and methods
available to most home owners aren't very effective. Compared to commercial
carpet cleaning equipment, the carpet cleaning machines you rent from the local
supermarket are like a moped is to a Harley. They're the same thing, but not really.
Getting
anything other than a light smell out of a carpet requires the high pressure
and suction of a commercial machine. It also requires the expertise of a
trained and experienced carpet cleaner. There are many causes and solutions to
different smells in a carpet and knowing what to do and when to do it requires
training and experience.
If
baking soda and vacuuming don't work, your best bet is to call a trained and
experienced carpet cleaner, preferably one that is also an IICRC certified Odor
Control Technician.
Myth
#8. If you dry a flooded carpet, you will not get a moldy wet carpet smell
Depends.
If a carpet is dried quickly and properly there will be no smell. In fact, if
anything, there will be less smell because the carpet has effectively been cleaned.
If
the carpet and pad are not dried quickly and properly you will probably have a
problem with lingering musky smells and mold.
See
question 2 for more details.
Myth
#9. You have to use a truck mount carpet extractor to dry or clean a carpet
properly
False.
This is an ongoing debate that I don't think will ever be resolved completely.
Portable carpet cleaning machines have the advantage of short hose runs while
truck mounts have the advantage of high power.
What
it comes down to is really the technician holding the wand. A good technician
on a bad machine will get a better result than a bad technician on a good
machine.