Hi all,

I have a 95 yo basement with a decaying floor that wicks moisture into
anything you rest on it. I installed a sump pump which helped, but
didn't solve it. There may be an issue with a high water table or a
natural spring. The cement is aged and cracked, but basically sound.
A few spots heaved up for some reason (Continental drift contributing
to mountain building forces perhaps? g), and the entire floor has a
(coal?) cinder base under it. If I put a piece of plastic down in any
spot for more than a day, it gets quite moist underneath. Since my
workshop is there, the dampness is causing all my tools to rust.

The proper solution here is to hammer up the floor, remove the cinder
base, level the dirt, lay a smooth gravel bed, and have a truck back up
to the vent window while a 4-man crew spreads a new slab. The proper
solution is also a lot more expensive and time consuming than I can
currently manage. I would have to remove the old floor to maintain my
head clearance which is already a little tight, and the basement has no
direct access to my back yard.

The improper solution I came up with is to remove and patch the heaves,
and then use latex fortified thinset with cement fiber backer board
over the whole floor. I would close the seems it with fiber tape and
thinset, and pour a leveling compound over the entire mess. After the
proper curing time, a quick coat of epoxy paint to finish it off.
Instead of a 3" or 4" floor raise, I would be looking at a 1/2"
to 3/4" one. It also seams like this solution would be strong,
watertight, and look attractive.

Any reason why I shouldn't pursue it? IOW, Could someone please talk
me out of this? Also, does anyone have an alternative to the two
approaches mentioned above?

Many thanks in advance.

Check out these water control tiling systems

http://www.schluter.com/english/prod...section-f.html

Familiar to some is the Kerdi system but the Ditra system looks like it
might fit your needs. Call them to discuss which is best for your
situation.

Yours sounds like an appropriate application for these more advanced tile
substrates.


wrote in message
oups.com...
Hi all,

I have a 95 yo basement with a decaying floor that wicks moisture into
anything you rest on it. I installed a sump pump which helped, but
didn't solve it. There may be an issue with a high water table or a
natural spring. The cement is aged and cracked, but basically sound.
A few spots heaved up for some reason (Continental drift contributing
to mountain building forces perhaps? g), and the entire floor has a
(coal?) cinder base under it. If I put a piece of plastic down in any
spot for more than a day, it gets quite moist underneath. Since my
workshop is there, the dampness is causing all my tools to rust.

The proper solution here is to hammer up the floor, remove the cinder
base, level the dirt, lay a smooth gravel bed, and have a truck back up
to the vent window while a 4-man crew spreads a new slab. The proper
solution is also a lot more expensive and time consuming than I can
currently manage. I would have to remove the old floor to maintain my
head clearance which is already a little tight, and the basement has no
direct access to my back yard.

The improper solution I came up with is to remove and patch the heaves,
and then use latex fortified thinset with cement fiber backer board
over the whole floor. I would close the seems it with fiber tape and
thinset, and pour a leveling compound over the entire mess. After the
proper curing time, a quick coat of epoxy paint to finish it off.
Instead of a 3" or 4" floor raise, I would be looking at a 1/2"
to 3/4" one. It also seams like this solution would be strong,
watertight, and look attractive.

Any reason why I shouldn't pursue it? IOW, Could someone please talk
me out of this? Also, does anyone have an alternative to the two
approaches mentioned above?

Many thanks in advance.

On 21 Apr 2006 10:59:42 -0700, wrote:

Hi all,

I have a 95 yo basement with a decaying floor that wicks moisture into
anything you rest on it. I installed a sump pump which helped, but
didn't solve it. There may be an issue with a high water table or a
natural spring. The cement is aged and cracked, but basically sound.
A few spots heaved up for some reason (Continental drift contributing
to mountain building forces perhaps? g), and the entire floor has a
(coal?) cinder base under it. If I put a piece of plastic down in any
spot for more than a day, it gets quite moist underneath. Since my
workshop is there, the dampness is causing all my tools to rust.

The proper solution here is to hammer up the floor, remove the cinder
base, level the dirt, lay a smooth gravel bed, and have a truck back up
to the vent window while a 4-man crew spreads a new slab. The proper
solution is also a lot more expensive and time consuming than I can
currently manage. I would have to remove the old floor to maintain my
head clearance which is already a little tight, and the basement has no
direct access to my back yard.

The improper solution I came up with is to remove and patch the heaves,
and then use latex fortified thinset with cement fiber backer board
over the whole floor. I would close the seems it with fiber tape and
thinset, and pour a leveling compound over the entire mess. After the
proper curing time, a quick coat of epoxy paint to finish it off.
Instead of a 3" or 4" floor raise, I would be looking at a 1/2"
to 3/4" one. It also seams like this solution would be strong,
watertight, and look attractive.

Any reason why I shouldn't pursue it? IOW, Could someone please talk
me out of this? Also, does anyone have an alternative to the two
approaches mentioned above?

Many thanks in advance.

Depends how long you want the fix to last. If you've got
water working up through the floor, then either the
coating you put on the concrete will fail, or the
concrete itself will fail. It will probably work
for a while, though. If you're even considering
eventually doing a real fix, then I'd say just
run a pair of dehumidifiers down there constantly,

Interesting, PipeDown, but that stuff looks a little advanced for me.
Also looks a little pricy. The nice thing about the backer board fix
is that they sell everything I need at the Home Depot.

You're looking for a complicated answer to a simple problem. Like the man
said, just get a dehumidifier. Let it drain into the sump pump. It will
have a sensor to turn off when enough moisture has been removed. Also, when
its warm enough, open the windows.

S

On your sump pump? Did you install a drain field or just a pump
somewhere?

Using a jackhammer dig some paths to the sump from different areas of
the basement, dig down a foot or so haul away the dirt and broken
concrete, lay that 4 inch flexible perforated drainpipe in the hole
after first installing a little gravel as a base then cover the
perforated drain pipe with gravel and cement floor back.

repair floors bad areas, run pipe thru them, then atch cement floor,
wait a month or two and paint if you want.

add dehumidifier and let run year round or put a small fan in a 4 inch
duct and let run to ventilate the area.

I ave fought water, you cant seal it out you can divert it
successfully!

make sure sump drains well away from home, yard slopes from home and
downspout water all goes well away from home

this is all basic basement drying 101

I believe because of the continued moisture problem,
the thinset would eventually release the cementboard
and you'd end up with a "floating floor". All the parts
of your solution are also sensitive to ground movement,
which would also make the cementboard shear, and
the leveling compound will release. Leveling compound
is meant for a completely stable floor, and in the tile
trade it is meant to be covered right away- not as a
finish coat.

As others have said, you need to deal with the moisture.
Containing the moisture, as you propose, is very risky
and opens up other problems such as effloresence (sp?)
where moisture under thinset, cementcoat or grout causes
salts to leach out of the cement. I've seen this happen many
times, _always_ in the presence of continued moisture such
as you have.

The simplest solution I can think of is to skim coat it with
a mix of 50% flexible thinset (the expensive stuff), and
50% clean sand. Your floor should be super clean before
doing it, and consider painting a latex "link" on your slab
before doing it. As you skim coat it, scratch the coating
real hard into your floor to get a good bond. When I skim
coat, I use a notched trowel to scratch the coating into the
floor, then a flat trowel to level it. It's like if you drop a
booger onto your pant leg, you can lift it off, but if you
smear it in........it sticks pretty good......

Oh and as has been mentioned, de-umidifiers work great.
We live in Florida and used one in a non-air conditioned
storage room we had, and it kept the room dry.

Have fun,

thetiler

wrote on 21 Apr 2006:

You think 15 years would be too much to hope for?

Depends on your level of optimism. How likely do you think it is
that you'll win the lottery?

OTOH, a good dehumidifier can last that long.

My biggest
concern is in using leveling compound as a surface. It's
generally intended to be covered by something. I'm not sure how
soft it is; if it will spall when I drop a hammer on it.

There are a number of kinds of leveling compound. The cheaper ones
tend to break up fairly easily. The more expensive ones won't, but
you might just as well use gold to do the job. OK, maybe silver.

Have you considered the possibility that the water is coming from
overflowing gutters and downspouts emptying out too close to the
house? Or yard sloped toward the house? Those are very cheap to
fix.

--
Doug Boulter

To reply by e-mail, remove the obvious word from the e-mail address

The pump is in the wettest part of the floor, and drains into a floor
drain. Eventually, I'll need to hammer up and replace my cast drain
line with PVC. At that time, I'll lay a drain tile. I was toying
with the idea of drilling and running drainage pipes under the
foundation to the outside every three feet or so to collect and
redirect additional moisture before it can build up and reach the wall
(which is also moist).

My home is a philadelphia twin with only a four foot thick strip of
grass between me and my neighbor. There is a paved sidewalk directly
against my house that extends a few feet, so I know that runoff isn't
an issue. The roof is a flat roof and I redirected the discharge
through a 4" corrugated underground to a French well in my back yard.


I *really* wish I knew where the water was coming from. It's why I
suspect a spring or a high water table. The big problem with that
theory is that my neighbors report dry basements. I purchased a
dehumidifier last year with an automatic humidistat. I just can't
stand using all that energy on it. They aren't the most efficient
devices. I guess it beats buying new tools, however.

Thanks for the input.
-Tom

Hi Tilier. Thanks for the thourough analysis.

Having a floating floor was my fear. The weakest part of it would be
the seams. After reading everyone's feedback, I'm guessing I would
have a beautiful finished floor for a year, and then a gridwork of
cracks running through them leaking moisture. Each year it would look
worse until it completely fell to pieces. I guess I'll back off.
Thanks for talking me out of it.

The sand / thinset solution is intriguing. Great analogy with the
booger. I swear I've never done that before, yet I know exactly what
you mean. Half of my intention is to solve the moisture problem, the
other half is to make it look nice and tidy. I'm pretty sure I could
strike a smooth clean surface with my pool trowel. Also, for the latex
"link", someone once told me that the throw-away latex paint that
sells for $2.00 / gallon works great for this as opposed to the $30 /
oz. sold by the good folks at Quickcrete. Any thoughts on this?

Thanks again,
Tom

Do I have to use sterling silver, or can I use coin g?

wrote on 23 Apr 2006:

My home is a philadelphia twin with only a four foot thick strip
of grass between me and my neighbor. There is a paved sidewalk
directly against my house that extends a few feet, so I know
that runoff isn't an issue.

Hmmmm, what about your neighbor's gutters?

Seriously, if a lot of water (from a heavy rain or from gutters) is
coming down in that 4' strip, it's going to go somewhere, and if
it's landing on your paved sidewalk and flowing to your neighbor's
house, it may be coming back at you once it gets into the ground.
Might be worthwhile to stand outside and watch things the next good
rain you get.

The good news is that if you ever decide to fix things from the
outside, you only have one side of the house to dig up, and it
sounds as if you could get a Bobcat in there if you're careful.

--
Doug Boulter

To reply by e-mail, remove the obvious word from the e-mail address

Hmmmm, what about your neighbor's gutters?

We both have flat roofs. My roof used to discharge onto the sidewalk
before I dug up a sidewalk square and buried proper drainage away from
the house. The front pipe discharges to the public sewage system.
Both my neighbors pipes also discharge to the sewage system as well.
These were the first steps I took.

Paint is a terribly hard thing to stick to with cement products. In my
experience
of tens of thousands of tiles removed with chisel hammers, paint will
release
thinset faster than anything, so in my experience, it acts the opposite
of a "link".

Real "link" is that blue gooey stuff that is made specifically to link
new cement
to an old cement floor. I don't think it's expensive, and you simply
brush a
coating on and let it get tacky before applying the new cement mix.

Another option would be to make your own polymer thinset by combining
latex additive (made to be added to thinset) with plain thinset. Use
this
same latex liquid as a link by brushing it on straight, then letting it
dry
before you skimcoat with the latex/thinset mix.

You need to be careful to never mix latex additive to thinset that is
already
latex modified in it's dry form. If you use liquid additive, use
plain
thinset (the cheap stuff).

thetiler

I put some leveling compound to fill a hole around a spot where a
shower drain pipe comes thru basement floor. I been used twice and is
currently unused and capped off.

its a moist area and i checked the leveling compound is detoriating.

doesnt matter to me when theres money its new sewer time and that area
is a goner

If you can't afford to do it right then you surely can't afford to do
it wrong and then do it over.

A big notched trowel is fine, remember it's purpose is to scrape
"key" the thinset mix into the existing cement. Your flat trowel
is what you will finish it with. It only needs to be as thick as
you need to level the floor...more where you have a dip, and less
where you have a hump....
I would use a workable mix, as you say "pancake batter", but
not weak or runny. Maybe more like soft peanut butter. A dry
mix would be hard for you to work with.
A good "pre-mixed" dry mix would be wall mud, which is what
is used to make "mud job" shower jobs. It has sand, cement,
carotex (sp?) which makes it sticky, and light particles like
styrofoam tiny balls or formiculite (sp?) to be a filler and make
it light. It's easily spreadable and easy to work with, and shouldn't
cost more than multi purpose thinset. It sticks like crazy, and is
strong in the long run (try to tear out a mud wall sometime).

Remember, all my ideas are jury-riggs meant to patch your
floor, not professional advice. Outside of professional tiling,
I often jury rig my own projects, so I know where you are coming
from, but you must assume responsibility for not tearing out the
floor, dealing with your water problem, or pouring a new slab.
The principles behind my ideas are to 1) have a mix that will
allow water to pass through and evaporate, thereby not trapping
the moisture underneath, and 2) make a mix that is sticky enough
to bond as long as possible, yet be strong also.
I try to do high quality jury riggs :-)

thetiler